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<span>Refraction</span> </div> </a> <ul id="toc-Refraction-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Light_sources" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Light_sources"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Light sources</span> </div> </a> <ul id="toc-Light_sources-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Measurement" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Measurement"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Measurement</span> </div> </a> <ul id="toc-Measurement-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Light_pressure" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Light_pressure"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Light pressure</span> </div> </a> <ul id="toc-Light_pressure-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Historical_theories_about_light,_in_chronological_order" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Historical_theories_about_light,_in_chronological_order"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Historical theories about light, in chronological order</span> </div> </a> <button aria-controls="toc-Historical_theories_about_light,_in_chronological_order-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Historical theories about light, in chronological order subsection</span> </button> <ul id="toc-Historical_theories_about_light,_in_chronological_order-sublist" class="vector-toc-list"> <li id="toc-Classical_Greece_and_Hellenism" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Classical_Greece_and_Hellenism"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.1</span> <span>Classical Greece and Hellenism</span> </div> </a> <ul id="toc-Classical_Greece_and_Hellenism-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Classical_India" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Classical_India"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.2</span> <span>Classical India</span> </div> </a> <ul id="toc-Classical_India-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Descartes" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Descartes"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.3</span> <span>Descartes</span> </div> </a> <ul id="toc-Descartes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Particle_theory" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Particle_theory"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.4</span> <span>Particle theory</span> </div> </a> <ul id="toc-Particle_theory-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Wave_theory" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Wave_theory"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.5</span> <span>Wave theory</span> </div> </a> <ul id="toc-Wave_theory-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Electromagnetic_theory" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Electromagnetic_theory"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.6</span> <span>Electromagnetic theory</span> </div> </a> <ul id="toc-Electromagnetic_theory-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Quantum_theory" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Quantum_theory"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.7</span> <span>Quantum theory</span> </div> </a> <ul id="toc-Quantum_theory-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Quantum_optics" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Quantum_optics"> <div class="vector-toc-text"> <span class="vector-toc-numb">7.8</span> <span>Quantum optics</span> </div> </a> <ul id="toc-Quantum_optics-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Use_for_light_on_Earth" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Use_for_light_on_Earth"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Use for light on Earth</span> </div> </a> <ul id="toc-Use_for_light_on_Earth-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Notes" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Notes"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>Notes</span> </div> </a> <ul id="toc-Notes-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">11</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">12</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Light</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 180 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-180" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">180 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Lig" title="Lig – Afrikaans" lang="af" hreflang="af" data-title="Lig" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-als mw-list-item"><a href="https://als.wikipedia.org/wiki/Licht" title="Licht – Alemannic" lang="gsw" hreflang="gsw" data-title="Licht" data-language-autonym="Alemannisch" data-language-local-name="Alemannic" class="interlanguage-link-target"><span>Alemannisch</span></a></li><li class="interlanguage-link interwiki-am mw-list-item"><a href="https://am.wikipedia.org/wiki/%E1%89%A5%E1%88%AD%E1%88%83%E1%8A%95" title="ብርሃን – Amharic" lang="am" hreflang="am" data-title="ብርሃን" data-language-autonym="አማርኛ" data-language-local-name="Amharic" class="interlanguage-link-target"><span>አማርኛ</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B6%D9%88%D8%A1" title="ضوء – Arabic" lang="ar" hreflang="ar" data-title="ضوء" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Luz" title="Luz – Aragonese" lang="an" hreflang="an" data-title="Luz" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-arc mw-list-item"><a href="https://arc.wikipedia.org/wiki/%DC%A2%DC%98%DC%97%DC%AA%DC%90_(%DC%9A%DC%99%DC%9D%DC%AC%DC%90)" title="ܢܘܗܪܐ (ܚܙܝܬܐ) – Aramaic" lang="arc" hreflang="arc" data-title="ܢܘܗܪܐ (ܚܙܝܬܐ)" data-language-autonym="ܐܪܡܝܐ" data-language-local-name="Aramaic" class="interlanguage-link-target"><span>ܐܪܡܝܐ</span></a></li><li class="interlanguage-link interwiki-hyw mw-list-item"><a href="https://hyw.wikipedia.org/wiki/%D4%BC%D5%B8%D5%B5%D5%BD" title="Լոյս – Western Armenian" lang="hyw" hreflang="hyw" data-title="Լոյս" data-language-autonym="Արեւմտահայերէն" data-language-local-name="Western Armenian" class="interlanguage-link-target"><span>Արեւմտահայերէն</span></a></li><li class="interlanguage-link interwiki-roa-rup mw-list-item"><a href="https://roa-rup.wikipedia.org/wiki/Lu%C5%84in%C3%A2" title="Luńinâ – Aromanian" lang="rup" hreflang="rup" data-title="Luńinâ" data-language-autonym="Armãneashti" data-language-local-name="Aromanian" class="interlanguage-link-target"><span>Armãneashti</span></a></li><li class="interlanguage-link interwiki-as mw-list-item"><a href="https://as.wikipedia.org/wiki/%E0%A6%AA%E0%A7%8B%E0%A6%B9%E0%A7%B0" title="পোহৰ – Assamese" lang="as" hreflang="as" data-title="পোহৰ" data-language-autonym="অসমীয়া" data-language-local-name="Assamese" class="interlanguage-link-target"><span>অসমীয়া</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Lluz" title="Lluz – Asturian" lang="ast" hreflang="ast" data-title="Lluz" data-language-autonym="Asturianu" data-language-local-name="Asturian" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-gn mw-list-item"><a href="https://gn.wikipedia.org/wiki/Tesape" title="Tesape – Guarani" lang="gn" hreflang="gn" data-title="Tesape" data-language-autonym="Avañe'ẽ" data-language-local-name="Guarani" class="interlanguage-link-target"><span>Avañe'ẽ</span></a></li><li class="interlanguage-link interwiki-ay mw-list-item"><a href="https://ay.wikipedia.org/wiki/Qhana" title="Qhana – Aymara" lang="ay" hreflang="ay" data-title="Qhana" data-language-autonym="Aymar aru" data-language-local-name="Aymara" class="interlanguage-link-target"><span>Aymar aru</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/%C4%B0%C5%9F%C4%B1q" title="İşıq – Azerbaijani" lang="az" hreflang="az" data-title="İşıq" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-azb mw-list-item"><a href="https://azb.wikipedia.org/wiki/%D8%A7%DB%8C%D8%B4%DB%8C%D9%82" title="ایشیق – South Azerbaijani" lang="azb" hreflang="azb" data-title="ایشیق" data-language-autonym="تۆرکجه" data-language-local-name="South Azerbaijani" class="interlanguage-link-target"><span>تۆرکجه</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%86%E0%A6%B2%E0%A7%8B" title="আলো – Bangla" lang="bn" hreflang="bn" data-title="আলো" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-zh-min-nan mw-list-item"><a href="https://zh-min-nan.wikipedia.org/wiki/Kng" title="Kng – Minnan" lang="nan" hreflang="nan" data-title="Kng" data-language-autonym="閩南語 / Bân-lâm-gú" data-language-local-name="Minnan" class="interlanguage-link-target"><span>閩南語 / Bân-lâm-gú</span></a></li><li class="interlanguage-link interwiki-ba mw-list-item"><a href="https://ba.wikipedia.org/wiki/%D0%AF%D2%A1%D1%82%D1%8B%D0%BB%D1%8B%D2%A1" title="Яҡтылыҡ – Bashkir" lang="ba" hreflang="ba" data-title="Яҡтылыҡ" data-language-autonym="Башҡортса" data-language-local-name="Bashkir" class="interlanguage-link-target"><span>Башҡортса</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%A1%D0%B2%D1%8F%D1%82%D0%BB%D0%BE" title="Святло – Belarusian" lang="be" hreflang="be" data-title="Святло" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%A1%D1%8C%D0%B2%D1%8F%D1%82%D0%BB%D0%BE" title="Сьвятло – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Сьвятло" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target"><span>Беларуская (тарашкевіца)</span></a></li><li class="interlanguage-link interwiki-bcl mw-list-item"><a href="https://bcl.wikipedia.org/wiki/Liwanag" title="Liwanag – Central Bikol" lang="bcl" hreflang="bcl" data-title="Liwanag" data-language-autonym="Bikol Central" data-language-local-name="Central Bikol" class="interlanguage-link-target"><span>Bikol Central</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%A1%D0%B2%D0%B5%D1%82%D0%BB%D0%B8%D0%BD%D0%B0" title="Светлина – Bulgarian" lang="bg" hreflang="bg" data-title="Светлина" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bar mw-list-item"><a href="https://bar.wikipedia.org/wiki/Liacht" title="Liacht – Bavarian" lang="bar" hreflang="bar" data-title="Liacht" data-language-autonym="Boarisch" data-language-local-name="Bavarian" class="interlanguage-link-target"><span>Boarisch</span></a></li><li class="interlanguage-link interwiki-bo mw-list-item"><a href="https://bo.wikipedia.org/wiki/%E0%BD%A0%E0%BD%BC%E0%BD%91%E0%BC%8D" title="འོད། – Tibetan" lang="bo" hreflang="bo" data-title="འོད།" data-language-autonym="བོད་ཡིག" data-language-local-name="Tibetan" class="interlanguage-link-target"><span>བོད་ཡིག</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Svjetlost" title="Svjetlost – Bosnian" lang="bs" hreflang="bs" data-title="Svjetlost" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Goulo%C3%B9" title="Gouloù – Breton" lang="br" hreflang="br" data-title="Gouloù" data-language-autonym="Brezhoneg" data-language-local-name="Breton" class="interlanguage-link-target"><span>Brezhoneg</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Llum" title="Llum – Catalan" lang="ca" hreflang="ca" data-title="Llum" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cv mw-list-item"><a href="https://cv.wikipedia.org/wiki/%C3%87%D1%83%D1%82%C4%83" title="Çутă – Chuvash" lang="cv" hreflang="cv" data-title="Çутă" data-language-autonym="Чӑвашла" data-language-local-name="Chuvash" class="interlanguage-link-target"><span>Чӑвашла</span></a></li><li class="interlanguage-link interwiki-ceb mw-list-item"><a href="https://ceb.wikipedia.org/wiki/Kahayag" title="Kahayag – Cebuano" lang="ceb" hreflang="ceb" data-title="Kahayag" data-language-autonym="Cebuano" data-language-local-name="Cebuano" class="interlanguage-link-target"><span>Cebuano</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Sv%C4%9Btlo" title="Světlo – Czech" lang="cs" hreflang="cs" data-title="Světlo" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-sn mw-list-item"><a href="https://sn.wikipedia.org/wiki/Chiedza" title="Chiedza – Shona" lang="sn" hreflang="sn" data-title="Chiedza" data-language-autonym="ChiShona" data-language-local-name="Shona" class="interlanguage-link-target"><span>ChiShona</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Goleuni" title="Goleuni – Welsh" lang="cy" hreflang="cy" data-title="Goleuni" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-dag mw-list-item"><a href="https://dag.wikipedia.org/wiki/Neesim" title="Neesim – Dagbani" lang="dag" hreflang="dag" data-title="Neesim" data-language-autonym="Dagbanli" data-language-local-name="Dagbani" class="interlanguage-link-target"><span>Dagbanli</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Lys" title="Lys – Danish" lang="da" hreflang="da" data-title="Lys" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-ary mw-list-item"><a href="https://ary.wikipedia.org/wiki/%D8%B4%D8%B9%D8%A7" title="شعا – Moroccan Arabic" lang="ary" hreflang="ary" data-title="شعا" data-language-autonym="الدارجة" data-language-local-name="Moroccan Arabic" class="interlanguage-link-target"><span>الدارجة</span></a></li><li class="interlanguage-link interwiki-pdc mw-list-item"><a href="https://pdc.wikipedia.org/wiki/Licht" title="Licht – Pennsylvania German" lang="pdc" hreflang="pdc" data-title="Licht" data-language-autonym="Deitsch" data-language-local-name="Pennsylvania German" class="interlanguage-link-target"><span>Deitsch</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Licht" title="Licht – German" lang="de" hreflang="de" data-title="Licht" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Valgus" title="Valgus – Estonian" lang="et" hreflang="et" data-title="Valgus" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%A6%CF%89%CF%82" title="Φως – Greek" lang="el" hreflang="el" data-title="Φως" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-es badge-Q17437798 badge-goodarticle mw-list-item" title="good article badge"><a href="https://es.wikipedia.org/wiki/Luz" title="Luz – Spanish" lang="es" hreflang="es" data-title="Luz" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Lumo" title="Lumo – Esperanto" lang="eo" hreflang="eo" data-title="Lumo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-ext mw-list-item"><a href="https://ext.wikipedia.org/wiki/Lus" title="Lus – Extremaduran" lang="ext" hreflang="ext" data-title="Lus" data-language-autonym="Estremeñu" data-language-local-name="Extremaduran" class="interlanguage-link-target"><span>Estremeñu</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Argi" title="Argi – Basque" lang="eu" hreflang="eu" data-title="Argi" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D9%86%D9%88%D8%B1" title="نور – Persian" lang="fa" hreflang="fa" data-title="نور" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-hif mw-list-item"><a href="https://hif.wikipedia.org/wiki/Prakaas" title="Prakaas – Fiji Hindi" lang="hif" hreflang="hif" data-title="Prakaas" data-language-autonym="Fiji Hindi" data-language-local-name="Fiji Hindi" class="interlanguage-link-target"><span>Fiji Hindi</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Lumi%C3%A8re" title="Lumière – French" lang="fr" hreflang="fr" data-title="Lumière" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-fy mw-list-item"><a href="https://fy.wikipedia.org/wiki/Ljocht" title="Ljocht – Western Frisian" lang="fy" hreflang="fy" data-title="Ljocht" data-language-autonym="Frysk" data-language-local-name="Western Frisian" class="interlanguage-link-target"><span>Frysk</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Solas" title="Solas – Irish" lang="ga" hreflang="ga" data-title="Solas" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Luz" title="Luz – Galician" lang="gl" hreflang="gl" data-title="Luz" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-inh mw-list-item"><a href="https://inh.wikipedia.org/wiki/%D0%A1%D0%B5%D1%80%D0%B4%D0%B0%D0%BB%D0%BE" title="Сердало – Ingush" lang="inh" hreflang="inh" data-title="Сердало" data-language-autonym="ГӀалгӀай" data-language-local-name="Ingush" class="interlanguage-link-target"><span>ГӀалгӀай</span></a></li><li class="interlanguage-link interwiki-gan mw-list-item"><a href="https://gan.wikipedia.org/wiki/%E5%85%89" title="光 – Gan" lang="gan" hreflang="gan" data-title="光" data-language-autonym="贛語" data-language-local-name="Gan" class="interlanguage-link-target"><span>贛語</span></a></li><li class="interlanguage-link interwiki-gu mw-list-item"><a href="https://gu.wikipedia.org/wiki/%E0%AA%AA%E0%AB%8D%E0%AA%B0%E0%AA%95%E0%AA%BE%E0%AA%B6" title="પ્રકાશ – Gujarati" lang="gu" hreflang="gu" data-title="પ્રકાશ" data-language-autonym="ગુજરાતી" data-language-local-name="Gujarati" class="interlanguage-link-target"><span>ગુજરાતી</span></a></li><li class="interlanguage-link interwiki-gom mw-list-item"><a href="https://gom.wikipedia.org/wiki/%E0%A4%89%E0%A4%9C%E0%A4%B5%E0%A4%BE%E0%A4%A1" title="उजवाड – Goan Konkani" lang="gom" hreflang="gom" data-title="उजवाड" data-language-autonym="गोंयची कोंकणी / Gõychi Konknni" data-language-local-name="Goan Konkani" class="interlanguage-link-target"><span>गोंयची कोंकणी / Gõychi Konknni</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%B9%9B" title="빛 – Korean" lang="ko" hreflang="ko" data-title="빛" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-ha mw-list-item"><a href="https://ha.wikipedia.org/wiki/Haske" title="Haske – Hausa" lang="ha" hreflang="ha" data-title="Haske" data-language-autonym="Hausa" data-language-local-name="Hausa" class="interlanguage-link-target"><span>Hausa</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%BC%D5%B8%D6%82%D5%B5%D5%BD" title="Լույս – Armenian" lang="hy" hreflang="hy" data-title="Լույս" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%AA%E0%A5%8D%E0%A4%B0%E0%A4%95%E0%A4%BE%E0%A4%B6" title="प्रकाश – Hindi" lang="hi" hreflang="hi" data-title="प्रकाश" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Svjetlost" title="Svjetlost – Croatian" lang="hr" hreflang="hr" data-title="Svjetlost" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-io mw-list-item"><a href="https://io.wikipedia.org/wiki/Lumo" title="Lumo – Ido" lang="io" hreflang="io" data-title="Lumo" data-language-autonym="Ido" data-language-local-name="Ido" class="interlanguage-link-target"><span>Ido</span></a></li><li class="interlanguage-link interwiki-ilo mw-list-item"><a href="https://ilo.wikipedia.org/wiki/Lawag" title="Lawag – Iloko" lang="ilo" hreflang="ilo" data-title="Lawag" data-language-autonym="Ilokano" data-language-local-name="Iloko" class="interlanguage-link-target"><span>Ilokano</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Cahaya" title="Cahaya – Indonesian" lang="id" hreflang="id" data-title="Cahaya" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ia mw-list-item"><a href="https://ia.wikipedia.org/wiki/Lumine" title="Lumine – Interlingua" lang="ia" hreflang="ia" data-title="Lumine" data-language-autonym="Interlingua" data-language-local-name="Interlingua" class="interlanguage-link-target"><span>Interlingua</span></a></li><li class="interlanguage-link interwiki-ie mw-list-item"><a href="https://ie.wikipedia.org/wiki/L%C3%BAmine" title="Lúmine – Interlingue" lang="ie" hreflang="ie" data-title="Lúmine" data-language-autonym="Interlingue" data-language-local-name="Interlingue" class="interlanguage-link-target"><span>Interlingue</span></a></li><li class="interlanguage-link interwiki-zu mw-list-item"><a href="https://zu.wikipedia.org/wiki/Ukukhanya" title="Ukukhanya – Zulu" lang="zu" hreflang="zu" data-title="Ukukhanya" data-language-autonym="IsiZulu" data-language-local-name="Zulu" class="interlanguage-link-target"><span>IsiZulu</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Lj%C3%B3s" title="Ljós – Icelandic" lang="is" hreflang="is" data-title="Ljós" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Luce" title="Luce – Italian" lang="it" hreflang="it" data-title="Luce" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%90%D7%95%D7%A8" title="אור – Hebrew" lang="he" hreflang="he" data-title="אור" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-jv mw-list-item"><a href="https://jv.wikipedia.org/wiki/Cahya" title="Cahya – Javanese" lang="jv" hreflang="jv" data-title="Cahya" data-language-autonym="Jawa" data-language-local-name="Javanese" class="interlanguage-link-target"><span>Jawa</span></a></li><li class="interlanguage-link interwiki-kn mw-list-item"><a href="https://kn.wikipedia.org/wiki/%E0%B2%AC%E0%B3%86%E0%B2%B3%E0%B2%95%E0%B3%81" title="ಬೆಳಕು – Kannada" lang="kn" hreflang="kn" data-title="ಬೆಳಕು" data-language-autonym="ಕನ್ನಡ" data-language-local-name="Kannada" class="interlanguage-link-target"><span>ಕನ್ನಡ</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%A1%E1%83%98%E1%83%9C%E1%83%90%E1%83%97%E1%83%9A%E1%83%94" title="სინათლე – Georgian" lang="ka" hreflang="ka" data-title="სინათლე" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-ks mw-list-item"><a href="https://ks.wikipedia.org/wiki/%DA%AF%D8%A7%D8%B4" title="گاش – Kashmiri" lang="ks" hreflang="ks" data-title="گاش" data-language-autonym="कॉशुर / کٲشُر" data-language-local-name="Kashmiri" class="interlanguage-link-target"><span>कॉशुर / کٲشُر</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%96%D0%B0%D1%80%D1%8B%D2%9B" title="Жарық – Kazakh" lang="kk" hreflang="kk" data-title="Жарық" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-sw mw-list-item"><a href="https://sw.wikipedia.org/wiki/Nuru" title="Nuru – Swahili" lang="sw" hreflang="sw" data-title="Nuru" data-language-autonym="Kiswahili" data-language-local-name="Swahili" class="interlanguage-link-target"><span>Kiswahili</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/Limy%C3%A8" title="Limyè – Haitian Creole" lang="ht" hreflang="ht" data-title="Limyè" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-gcr mw-list-item"><a href="https://gcr.wikipedia.org/wiki/Limy%C3%A8" title="Limyè – Guianan Creole" lang="gcr" hreflang="gcr" data-title="Limyè" data-language-autonym="Kriyòl gwiyannen" data-language-local-name="Guianan Creole" class="interlanguage-link-target"><span>Kriyòl gwiyannen</span></a></li><li class="interlanguage-link interwiki-ku mw-list-item"><a href="https://ku.wikipedia.org/wiki/Ronah%C3%AE_(fiz%C3%AEk)" title="Ronahî (fizîk) – Kurdish" lang="ku" hreflang="ku" data-title="Ronahî (fizîk)" data-language-autonym="Kurdî" data-language-local-name="Kurdish" class="interlanguage-link-target"><span>Kurdî</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%96%D0%B0%D1%80%D1%8B%D0%BA" title="Жарык – Kyrgyz" lang="ky" hreflang="ky" data-title="Жарык" data-language-autonym="Кыргызча" data-language-local-name="Kyrgyz" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Lux" title="Lux – Latin" lang="la" hreflang="la" data-title="Lux" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Gaisma" title="Gaisma – Latvian" lang="lv" hreflang="lv" data-title="Gaisma" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Liicht" title="Liicht – Luxembourgish" lang="lb" hreflang="lb" data-title="Liicht" data-language-autonym="Lëtzebuergesch" data-language-local-name="Luxembourgish" class="interlanguage-link-target"><span>Lëtzebuergesch</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/%C5%A0viesa" title="Šviesa – Lithuanian" lang="lt" hreflang="lt" data-title="Šviesa" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lij mw-list-item"><a href="https://lij.wikipedia.org/wiki/Luxe" title="Luxe – Ligurian" lang="lij" hreflang="lij" data-title="Luxe" data-language-autonym="Ligure" data-language-local-name="Ligurian" class="interlanguage-link-target"><span>Ligure</span></a></li><li class="interlanguage-link interwiki-li mw-list-item"><a href="https://li.wikipedia.org/wiki/L%C3%A8ch" title="Lèch – Limburgish" lang="li" hreflang="li" data-title="Lèch" data-language-autonym="Limburgs" data-language-local-name="Limburgish" class="interlanguage-link-target"><span>Limburgs</span></a></li><li class="interlanguage-link interwiki-lfn mw-list-item"><a href="https://lfn.wikipedia.org/wiki/Lus" title="Lus – Lingua Franca Nova" lang="lfn" hreflang="lfn" data-title="Lus" data-language-autonym="Lingua Franca Nova" data-language-local-name="Lingua Franca Nova" class="interlanguage-link-target"><span>Lingua Franca Nova</span></a></li><li class="interlanguage-link interwiki-jbo mw-list-item"><a href="https://jbo.wikipedia.org/wiki/gusni" title="gusni – Lojban" lang="jbo" hreflang="jbo" data-title="gusni" data-language-autonym="La .lojban." data-language-local-name="Lojban" class="interlanguage-link-target"><span>La .lojban.</span></a></li><li class="interlanguage-link interwiki-lg mw-list-item"><a href="https://lg.wikipedia.org/wiki/Ekitangaala" title="Ekitangaala – Ganda" lang="lg" hreflang="lg" data-title="Ekitangaala" data-language-autonym="Luganda" data-language-local-name="Ganda" class="interlanguage-link-target"><span>Luganda</span></a></li><li class="interlanguage-link interwiki-lmo mw-list-item"><a href="https://lmo.wikipedia.org/wiki/L%C3%BCs" title="Lüs – Lombard" lang="lmo" hreflang="lmo" data-title="Lüs" data-language-autonym="Lombard" data-language-local-name="Lombard" class="interlanguage-link-target"><span>Lombard</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/F%C3%A9ny" title="Fény – Hungarian" lang="hu" hreflang="hu" data-title="Fény" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%A1%D0%B2%D0%B5%D1%82%D0%BB%D0%B8%D0%BD%D0%B0" title="Светлина – Macedonian" lang="mk" hreflang="mk" data-title="Светлина" data-language-autonym="Македонски" data-language-local-name="Macedonian" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-mg mw-list-item"><a href="https://mg.wikipedia.org/wiki/Fahazavana" title="Fahazavana – Malagasy" lang="mg" hreflang="mg" data-title="Fahazavana" data-language-autonym="Malagasy" data-language-local-name="Malagasy" class="interlanguage-link-target"><span>Malagasy</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%AA%E0%B5%8D%E0%B4%B0%E0%B4%95%E0%B4%BE%E0%B4%B6%E0%B4%82" title="പ്രകാശം – Malayalam" lang="ml" hreflang="ml" data-title="പ്രകാശം" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target"><span>മലയാളം</span></a></li><li class="interlanguage-link interwiki-mr mw-list-item"><a href="https://mr.wikipedia.org/wiki/%E0%A4%AA%E0%A5%8D%E0%A4%B0%E0%A4%95%E0%A4%BE%E0%A4%B6" title="प्रकाश – Marathi" lang="mr" hreflang="mr" data-title="प्रकाश" data-language-autonym="मराठी" data-language-local-name="Marathi" class="interlanguage-link-target"><span>मराठी</span></a></li><li class="interlanguage-link interwiki-xmf mw-list-item"><a href="https://xmf.wikipedia.org/wiki/%E1%83%A1%E1%83%98%E1%83%9C%E1%83%97%E1%83%94" title="სინთე – Mingrelian" lang="xmf" hreflang="xmf" data-title="სინთე" data-language-autonym="მარგალური" data-language-local-name="Mingrelian" class="interlanguage-link-target"><span>მარგალური</span></a></li><li class="interlanguage-link interwiki-arz mw-list-item"><a href="https://arz.wikipedia.org/wiki/%D8%A7%D9%84%D9%86%D9%88%D8%B1" title="النور – Egyptian Arabic" lang="arz" hreflang="arz" data-title="النور" data-language-autonym="مصرى" data-language-local-name="Egyptian Arabic" class="interlanguage-link-target"><span>مصرى</span></a></li><li class="interlanguage-link interwiki-mzn mw-list-item"><a href="https://mzn.wikipedia.org/wiki/%D8%B3%D9%88" title="سو – Mazanderani" lang="mzn" hreflang="mzn" data-title="سو" data-language-autonym="مازِرونی" data-language-local-name="Mazanderani" class="interlanguage-link-target"><span>مازِرونی</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Cahaya" title="Cahaya – Malay" lang="ms" hreflang="ms" data-title="Cahaya" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-min mw-list-item"><a href="https://min.wikipedia.org/wiki/Cahayo" title="Cahayo – Minangkabau" lang="min" hreflang="min" data-title="Cahayo" data-language-autonym="Minangkabau" data-language-local-name="Minangkabau" class="interlanguage-link-target"><span>Minangkabau</span></a></li><li class="interlanguage-link interwiki-cdo mw-list-item"><a href="https://cdo.wikipedia.org/wiki/Gu%C5%8Fng" title="Guŏng – Mindong" lang="cdo" hreflang="cdo" data-title="Guŏng" data-language-autonym="閩東語 / Mìng-dĕ̤ng-ngṳ̄" data-language-local-name="Mindong" class="interlanguage-link-target"><span>閩東語 / Mìng-dĕ̤ng-ngṳ̄</span></a></li><li class="interlanguage-link interwiki-mwl mw-list-item"><a href="https://mwl.wikipedia.org/wiki/Lu%C3%A7" title="Luç – Mirandese" lang="mwl" hreflang="mwl" data-title="Luç" data-language-autonym="Mirandés" data-language-local-name="Mirandese" class="interlanguage-link-target"><span>Mirandés</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%93%D1%8D%D1%80%D1%8D%D0%BB" title="Гэрэл – Mongolian" lang="mn" hreflang="mn" data-title="Гэрэл" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-my mw-list-item"><a href="https://my.wikipedia.org/wiki/%E1%80%A1%E1%80%9C%E1%80%84%E1%80%BA%E1%80%B8" title="အလင်း – Burmese" lang="my" hreflang="my" data-title="အလင်း" data-language-autonym="မြန်မာဘာသာ" data-language-local-name="Burmese" class="interlanguage-link-target"><span>မြန်မာဘာသာ</span></a></li><li class="interlanguage-link interwiki-nah mw-list-item"><a href="https://nah.wikipedia.org/wiki/Tl%C4%81hu%C4%ABlli" title="Tlāhuīlli – Nahuatl" lang="nah" hreflang="nah" data-title="Tlāhuīlli" data-language-autonym="Nāhuatl" data-language-local-name="Nahuatl" class="interlanguage-link-target"><span>Nāhuatl</span></a></li><li class="interlanguage-link interwiki-fj mw-list-item"><a href="https://fj.wikipedia.org/wiki/Rarama" title="Rarama – Fijian" lang="fj" hreflang="fj" data-title="Rarama" data-language-autonym="Na Vosa Vakaviti" data-language-local-name="Fijian" class="interlanguage-link-target"><span>Na Vosa Vakaviti</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Licht" title="Licht – Dutch" lang="nl" hreflang="nl" data-title="Licht" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-nds-nl mw-list-item"><a href="https://nds-nl.wikipedia.org/wiki/Locht_(straoling)" title="Locht (straoling) – Low Saxon" lang="nds-NL" hreflang="nds-NL" data-title="Locht (straoling)" data-language-autonym="Nedersaksies" data-language-local-name="Low Saxon" class="interlanguage-link-target"><span>Nedersaksies</span></a></li><li class="interlanguage-link interwiki-ne mw-list-item"><a href="https://ne.wikipedia.org/wiki/%E0%A4%AA%E0%A5%8D%E0%A4%B0%E0%A4%95%E0%A4%BE%E0%A4%B6" title="प्रकाश – Nepali" lang="ne" hreflang="ne" data-title="प्रकाश" data-language-autonym="नेपाली" data-language-local-name="Nepali" class="interlanguage-link-target"><span>नेपाली</span></a></li><li class="interlanguage-link interwiki-new mw-list-item"><a href="https://new.wikipedia.org/wiki/%E0%A4%9C%E0%A4%83" title="जः – Newari" lang="new" hreflang="new" data-title="जः" data-language-autonym="नेपाल भाषा" data-language-local-name="Newari" class="interlanguage-link-target"><span>नेपाल भाषा</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E5%85%89" title="光 – Japanese" lang="ja" hreflang="ja" data-title="光" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-nap mw-list-item"><a href="https://nap.wikipedia.org/wiki/Luce" title="Luce – Neapolitan" lang="nap" hreflang="nap" data-title="Luce" data-language-autonym="Napulitano" data-language-local-name="Neapolitan" class="interlanguage-link-target"><span>Napulitano</span></a></li><li class="interlanguage-link interwiki-frr mw-list-item"><a href="https://frr.wikipedia.org/wiki/Laacht" title="Laacht – Northern Frisian" lang="frr" hreflang="frr" data-title="Laacht" data-language-autonym="Nordfriisk" data-language-local-name="Northern Frisian" class="interlanguage-link-target"><span>Nordfriisk</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Lys" title="Lys – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Lys" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Lys" title="Lys – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Lys" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-nrm mw-list-item"><a href="https://nrm.wikipedia.org/wiki/Lumyire" title="Lumyire – Norman" lang="nrf" hreflang="nrf" data-title="Lumyire" data-language-autonym="Nouormand" data-language-local-name="Norman" class="interlanguage-link-target"><span>Nouormand</span></a></li><li class="interlanguage-link interwiki-nov mw-list-item"><a href="https://nov.wikipedia.org/wiki/Lume" title="Lume – Novial" lang="nov" hreflang="nov" data-title="Lume" data-language-autonym="Novial" data-language-local-name="Novial" class="interlanguage-link-target"><span>Novial</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Lutz" title="Lutz – Occitan" lang="oc" hreflang="oc" data-title="Lutz" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-or mw-list-item"><a href="https://or.wikipedia.org/wiki/%E0%AC%86%E0%AC%B2%E0%AD%8B%E0%AC%95" title="ଆଲୋକ – Odia" lang="or" hreflang="or" data-title="ଆଲୋକ" data-language-autonym="ଓଡ଼ିଆ" data-language-local-name="Odia" class="interlanguage-link-target"><span>ଓଡ଼ିଆ</span></a></li><li class="interlanguage-link interwiki-om mw-list-item"><a href="https://om.wikipedia.org/wiki/Ifa" title="Ifa – Oromo" lang="om" hreflang="om" data-title="Ifa" data-language-autonym="Oromoo" data-language-local-name="Oromo" class="interlanguage-link-target"><span>Oromoo</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Yorug%CA%BBlik" title="Yorugʻlik – Uzbek" lang="uz" hreflang="uz" data-title="Yorugʻlik" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="Uzbek" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%AA%E0%A9%8D%E0%A8%B0%E0%A8%95%E0%A8%BE%E0%A8%B8%E0%A8%BC" title="ਪ੍ਰਕਾਸ਼ – Punjabi" lang="pa" hreflang="pa" data-title="ਪ੍ਰਕਾਸ਼" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-pnb mw-list-item"><a href="https://pnb.wikipedia.org/wiki/%DA%86%D8%A7%D9%86%DD%A8" title="چانݨ – Western Punjabi" lang="pnb" hreflang="pnb" data-title="چانݨ" data-language-autonym="پنجابی" data-language-local-name="Western Punjabi" class="interlanguage-link-target"><span>پنجابی</span></a></li><li class="interlanguage-link interwiki-jam mw-list-item"><a href="https://jam.wikipedia.org/wiki/Lait" title="Lait – Jamaican Creole English" lang="jam" hreflang="jam" data-title="Lait" data-language-autonym="Patois" data-language-local-name="Jamaican Creole English" class="interlanguage-link-target"><span>Patois</span></a></li><li class="interlanguage-link interwiki-km mw-list-item"><a href="https://km.wikipedia.org/wiki/%E1%9E%96%E1%9E%93%E1%9F%92%E1%9E%9B%E1%9E%BA" title="ពន្លឺ – Khmer" lang="km" hreflang="km" data-title="ពន្លឺ" data-language-autonym="ភាសាខ្មែរ" data-language-local-name="Khmer" class="interlanguage-link-target"><span>ភាសាខ្មែរ</span></a></li><li class="interlanguage-link interwiki-pms mw-list-item"><a href="https://pms.wikipedia.org/wiki/Lus" title="Lus – Piedmontese" lang="pms" hreflang="pms" data-title="Lus" data-language-autonym="Piemontèis" data-language-local-name="Piedmontese" class="interlanguage-link-target"><span>Piemontèis</span></a></li><li class="interlanguage-link interwiki-nds mw-list-item"><a href="https://nds.wikipedia.org/wiki/Licht" title="Licht – Low German" lang="nds" hreflang="nds" data-title="Licht" data-language-autonym="Plattdüütsch" data-language-local-name="Low German" class="interlanguage-link-target"><span>Plattdüütsch</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/%C5%9Awiat%C5%82o" title="Światło – Polish" lang="pl" hreflang="pl" data-title="Światło" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Luz" title="Luz – Portuguese" lang="pt" hreflang="pt" data-title="Luz" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Lumin%C4%83" title="Lumină – Romanian" lang="ro" hreflang="ro" data-title="Lumină" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-qu mw-list-item"><a href="https://qu.wikipedia.org/wiki/Achkiy" title="Achkiy – Quechua" lang="qu" hreflang="qu" data-title="Achkiy" data-language-autonym="Runa Simi" data-language-local-name="Quechua" class="interlanguage-link-target"><span>Runa Simi</span></a></li><li class="interlanguage-link interwiki-rue mw-list-item"><a href="https://rue.wikipedia.org/wiki/%D0%A1%D0%B2%D1%96%D1%82%D0%BB%D0%BE" title="Світло – Rusyn" lang="rue" hreflang="rue" data-title="Світло" data-language-autonym="Русиньскый" data-language-local-name="Rusyn" class="interlanguage-link-target"><span>Русиньскый</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A1%D0%B2%D0%B5%D1%82" title="Свет – Russian" lang="ru" hreflang="ru" data-title="Свет" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sah mw-list-item"><a href="https://sah.wikipedia.org/wiki/%D0%A1%D1%8B%D1%80%D0%B4%D1%8B%D0%BA" title="Сырдык – Yakut" lang="sah" hreflang="sah" data-title="Сырдык" data-language-autonym="Саха тыла" data-language-local-name="Yakut" class="interlanguage-link-target"><span>Саха тыла</span></a></li><li class="interlanguage-link interwiki-sa mw-list-item"><a href="https://sa.wikipedia.org/wiki/%E0%A4%A6%E0%A5%8D%E0%A4%AF%E0%A5%81%E0%A4%A4%E0%A4%BF%E0%A4%B6%E0%A4%95%E0%A5%8D%E0%A4%A4%E0%A4%BF%E0%A4%83" title="द्युतिशक्तिः – Sanskrit" lang="sa" hreflang="sa" data-title="द्युतिशक्तिः" data-language-autonym="संस्कृतम्" data-language-local-name="Sanskrit" class="interlanguage-link-target"><span>संस्कृतम्</span></a></li><li class="interlanguage-link interwiki-sat mw-list-item"><a href="https://sat.wikipedia.org/wiki/%E1%B1%A2%E1%B1%9F%E1%B1%A8%E1%B1%A5%E1%B1%9F%E1%B1%9E" title="ᱢᱟᱨᱥᱟᱞ – Santali" lang="sat" hreflang="sat" data-title="ᱢᱟᱨᱥᱟᱞ" data-language-autonym="ᱥᱟᱱᱛᱟᱲᱤ" data-language-local-name="Santali" class="interlanguage-link-target"><span>ᱥᱟᱱᱛᱟᱲᱤ</span></a></li><li class="interlanguage-link interwiki-sco mw-list-item"><a href="https://sco.wikipedia.org/wiki/Licht" title="Licht – Scots" lang="sco" hreflang="sco" data-title="Licht" data-language-autonym="Scots" data-language-local-name="Scots" class="interlanguage-link-target"><span>Scots</span></a></li><li class="interlanguage-link interwiki-stq mw-list-item"><a href="https://stq.wikipedia.org/wiki/Lucht" title="Lucht – Saterland Frisian" lang="stq" hreflang="stq" data-title="Lucht" data-language-autonym="Seeltersk" data-language-local-name="Saterland Frisian" class="interlanguage-link-target"><span>Seeltersk</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Drita" title="Drita – Albanian" lang="sq" hreflang="sq" data-title="Drita" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-scn mw-list-item"><a href="https://scn.wikipedia.org/wiki/Luci" title="Luci – Sicilian" lang="scn" hreflang="scn" data-title="Luci" data-language-autonym="Sicilianu" data-language-local-name="Sicilian" class="interlanguage-link-target"><span>Sicilianu</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B6%86%E0%B6%BD%E0%B7%9D%E0%B6%9A%E0%B6%BA" title="ආලෝකය – Sinhala" lang="si" hreflang="si" data-title="ආලෝකය" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Light" title="Light – Simple English" lang="en-simple" hreflang="en-simple" data-title="Light" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sd mw-list-item"><a href="https://sd.wikipedia.org/wiki/%D8%B1%D9%88%D8%B4%D9%86%D9%8A" title="روشني – Sindhi" lang="sd" hreflang="sd" data-title="روشني" data-language-autonym="سنڌي" data-language-local-name="Sindhi" class="interlanguage-link-target"><span>سنڌي</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Vidite%C4%BEn%C3%A9_svetlo" title="Viditeľné svetlo – Slovak" lang="sk" hreflang="sk" data-title="Viditeľné svetlo" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Svetloba" title="Svetloba – Slovenian" lang="sl" hreflang="sl" data-title="Svetloba" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-szl mw-list-item"><a href="https://szl.wikipedia.org/wiki/%C5%9Awiat%C5%82o" title="Światło – Silesian" lang="szl" hreflang="szl" data-title="Światło" data-language-autonym="Ślůnski" data-language-local-name="Silesian" class="interlanguage-link-target"><span>Ślůnski</span></a></li><li class="interlanguage-link interwiki-so mw-list-item"><a href="https://so.wikipedia.org/wiki/Ileys" title="Ileys – Somali" lang="so" hreflang="so" data-title="Ileys" data-language-autonym="Soomaaliga" data-language-local-name="Somali" class="interlanguage-link-target"><span>Soomaaliga</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%DA%95%D9%88%D9%88%D9%86%D8%A7%DA%A9%DB%8C" title="ڕووناکی – Central Kurdish" lang="ckb" hreflang="ckb" data-title="ڕووناکی" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%A1%D0%B2%D0%B5%D1%82%D0%BB%D0%BE%D1%81%D1%82" title="Светлост – Serbian" lang="sr" hreflang="sr" data-title="Светлост" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Svetlost" title="Svetlost – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Svetlost" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-su mw-list-item"><a href="https://su.wikipedia.org/wiki/Cahya" title="Cahya – Sundanese" lang="su" hreflang="su" data-title="Cahya" data-language-autonym="Sunda" data-language-local-name="Sundanese" class="interlanguage-link-target"><span>Sunda</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Valo" title="Valo – Finnish" lang="fi" hreflang="fi" data-title="Valo" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Ljus" title="Ljus – Swedish" lang="sv" hreflang="sv" data-title="Ljus" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Liwanag" title="Liwanag – Tagalog" lang="tl" hreflang="tl" data-title="Liwanag" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%92%E0%AE%B3%E0%AE%BF" title="ஒளி – Tamil" lang="ta" hreflang="ta" data-title="ஒளி" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-kab mw-list-item"><a href="https://kab.wikipedia.org/wiki/Tafat" title="Tafat – Kabyle" lang="kab" hreflang="kab" data-title="Tafat" data-language-autonym="Taqbaylit" data-language-local-name="Kabyle" class="interlanguage-link-target"><span>Taqbaylit</span></a></li><li class="interlanguage-link interwiki-tt mw-list-item"><a href="https://tt.wikipedia.org/wiki/%D0%AF%D0%BA%D1%82%D1%8B%D0%BB%D1%8B%D0%BA" title="Яктылык – Tatar" lang="tt" hreflang="tt" data-title="Яктылык" data-language-autonym="Татарча / tatarça" data-language-local-name="Tatar" class="interlanguage-link-target"><span>Татарча / tatarça</span></a></li><li class="interlanguage-link interwiki-te mw-list-item"><a href="https://te.wikipedia.org/wiki/%E0%B0%95%E0%B0%BE%E0%B0%82%E0%B0%A4%E0%B0%BF" title="కాంతి – Telugu" lang="te" hreflang="te" data-title="కాంతి" data-language-autonym="తెలుగు" data-language-local-name="Telugu" class="interlanguage-link-target"><span>తెలుగు</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B9%81%E0%B8%AA%E0%B8%87" title="แสง – Thai" lang="th" hreflang="th" data-title="แสง" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-chr mw-list-item"><a href="https://chr.wikipedia.org/wiki/%E1%8E%A2%E1%8E%A6%E1%8E%A2" title="ᎢᎦᎢ – Cherokee" lang="chr" hreflang="chr" data-title="ᎢᎦᎢ" data-language-autonym="ᏣᎳᎩ" data-language-local-name="Cherokee" class="interlanguage-link-target"><span>ᏣᎳᎩ</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/I%C5%9F%C4%B1k" title="Işık – Turkish" lang="tr" hreflang="tr" data-title="Işık" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-tyv mw-list-item"><a href="https://tyv.wikipedia.org/wiki/%D0%A7%D1%8B%D1%80%D1%8B%D0%BA" title="Чырык – Tuvinian" lang="tyv" hreflang="tyv" data-title="Чырык" data-language-autonym="Тыва дыл" data-language-local-name="Tuvinian" class="interlanguage-link-target"><span>Тыва дыл</span></a></li><li class="interlanguage-link interwiki-udm mw-list-item"><a href="https://udm.wikipedia.org/wiki/%D0%AE%D0%B3%D1%8B%D1%82" title="Югыт – Udmurt" lang="udm" hreflang="udm" data-title="Югыт" data-language-autonym="Удмурт" data-language-local-name="Udmurt" class="interlanguage-link-target"><span>Удмурт</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A1%D0%B2%D1%96%D1%82%D0%BB%D0%BE" title="Світло – Ukrainian" lang="uk" hreflang="uk" data-title="Світло" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D8%B1%D9%88%D8%B4%D9%86%DB%8C" title="روشنی – Urdu" lang="ur" hreflang="ur" data-title="روشنی" data-language-autonym="اردو" data-language-local-name="Urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-za mw-list-item"><a href="https://za.wikipedia.org/wiki/Rongh" title="Rongh – Zhuang" lang="za" hreflang="za" data-title="Rongh" data-language-autonym="Vahcuengh" data-language-local-name="Zhuang" class="interlanguage-link-target"><span>Vahcuengh</span></a></li><li class="interlanguage-link interwiki-vec mw-list-item"><a href="https://vec.wikipedia.org/wiki/%C5%81uze" title="Łuze – Venetian" lang="vec" hreflang="vec" data-title="Łuze" data-language-autonym="Vèneto" data-language-local-name="Venetian" class="interlanguage-link-target"><span>Vèneto</span></a></li><li class="interlanguage-link interwiki-vep mw-list-item"><a href="https://vep.wikipedia.org/wiki/Vauktuz" title="Vauktuz – Veps" lang="vep" hreflang="vep" data-title="Vauktuz" data-language-autonym="Vepsän kel’" data-language-local-name="Veps" class="interlanguage-link-target"><span>Vepsän kel’</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/%C3%81nh_s%C3%A1ng" title="Ánh sáng – Vietnamese" lang="vi" hreflang="vi" data-title="Ánh sáng" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-vo mw-list-item"><a href="https://vo.wikipedia.org/wiki/Lit" title="Lit – Volapük" lang="vo" hreflang="vo" data-title="Lit" data-language-autonym="Volapük" data-language-local-name="Volapük" class="interlanguage-link-target"><span>Volapük</span></a></li><li class="interlanguage-link interwiki-fiu-vro mw-list-item"><a href="https://fiu-vro.wikipedia.org/wiki/Valgus" title="Valgus – Võro" lang="vro" hreflang="vro" data-title="Valgus" data-language-autonym="Võro" data-language-local-name="Võro" class="interlanguage-link-target"><span>Võro</span></a></li><li class="interlanguage-link interwiki-wa mw-list-item"><a href="https://wa.wikipedia.org/wiki/Loumire" title="Loumire – Walloon" lang="wa" hreflang="wa" data-title="Loumire" data-language-autonym="Walon" data-language-local-name="Walloon" class="interlanguage-link-target"><span>Walon</span></a></li><li class="interlanguage-link interwiki-zh-classical mw-list-item"><a href="https://zh-classical.wikipedia.org/wiki/%E5%85%89" title="光 – Literary Chinese" lang="lzh" hreflang="lzh" data-title="光" data-language-autonym="文言" data-language-local-name="Literary Chinese" class="interlanguage-link-target"><span>文言</span></a></li><li class="interlanguage-link interwiki-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Lamrag" title="Lamrag – Waray" lang="war" hreflang="war" data-title="Lamrag" data-language-autonym="Winaray" data-language-local-name="Waray" class="interlanguage-link-target"><span>Winaray</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E5%85%89" title="光 – Wu" lang="wuu" hreflang="wuu" data-title="光" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-ts mw-list-item"><a href="https://ts.wikipedia.org/wiki/Rivoningo" title="Rivoningo – Tsonga" lang="ts" hreflang="ts" data-title="Rivoningo" data-language-autonym="Xitsonga" data-language-local-name="Tsonga" class="interlanguage-link-target"><span>Xitsonga</span></a></li><li class="interlanguage-link interwiki-yi mw-list-item"><a href="https://yi.wikipedia.org/wiki/%D7%9C%D7%99%D7%9B%D7%98" title="ליכט – Yiddish" lang="yi" hreflang="yi" data-title="ליכט" data-language-autonym="ייִדיש" data-language-local-name="Yiddish" class="interlanguage-link-target"><span>ייִדיש</span></a></li><li class="interlanguage-link interwiki-yo mw-list-item"><a href="https://yo.wikipedia.org/wiki/%C3%8Cm%E1%BB%8D%CC%81l%E1%BA%B9%CC%80" title="Ìmọ́lẹ̀ – Yoruba" lang="yo" hreflang="yo" data-title="Ìmọ́lẹ̀" data-language-autonym="Yorùbá" data-language-local-name="Yoruba" class="interlanguage-link-target"><span>Yorùbá</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E5%85%89" title="光 – Cantonese" lang="yue" hreflang="yue" data-title="光" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-bat-smg mw-list-item"><a href="https://bat-smg.wikipedia.org/wiki/%C5%A0v%C4%97isa" title="Švėisa – Samogitian" lang="sgs" hreflang="sgs" data-title="Švėisa" data-language-autonym="Žemaitėška" data-language-local-name="Samogitian" class="interlanguage-link-target"><span>Žemaitėška</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E5%85%89" title="光 – Chinese" lang="zh" hreflang="zh" data-title="光" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-dtp mw-list-item"><a href="https://dtp.wikipedia.org/wiki/Naau" title="Naau – Central Dusun" lang="dtp" hreflang="dtp" data-title="Naau" data-language-autonym="Kadazandusun" data-language-local-name="Central Dusun" class="interlanguage-link-target"><span>Kadazandusun</span></a></li><li class="interlanguage-link interwiki-iba mw-list-item"><a href="https://iba.wikipedia.org/wiki/Penampak" title="Penampak – Iban" lang="iba" hreflang="iba" data-title="Penampak" data-language-autonym="Jaku Iban" data-language-local-name="Iban" class="interlanguage-link-target"><span>Jaku Iban</span></a></li><li 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For other uses, see <a href="/wiki/Visible_light_(disambiguation)" class="mw-disambig" title="Visible light (disambiguation)">Visible light (disambiguation)</a>.</div> <p class="mw-empty-elt"> </p> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Prism_flat_rainbow_(cropped).jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Prism_flat_rainbow_%28cropped%29.jpg/290px-Prism_flat_rainbow_%28cropped%29.jpg" decoding="async" width="290" height="290" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Prism_flat_rainbow_%28cropped%29.jpg/435px-Prism_flat_rainbow_%28cropped%29.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/fa/Prism_flat_rainbow_%28cropped%29.jpg/580px-Prism_flat_rainbow_%28cropped%29.jpg 2x" data-file-width="3056" data-file-height="3056" /></a><figcaption>A triangular <a href="/wiki/Dispersive_prism" title="Dispersive prism">prism</a> <a href="/wiki/Dispersion_(optics)" title="Dispersion (optics)">dispersing</a> a beam of white light. 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.sidebar:not(.notheme) .sidebar-list-title,html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle{background:transparent!important}html.skin-theme-clientpref-night .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle a{color:var(--color-progressive)!important}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-list-title,html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle{background:transparent!important}html.skin-theme-clientpref-os .mw-parser-output .sidebar:not(.notheme) .sidebar-title-with-pretitle a{color:var(--color-progressive)!important}}@media print{body.ns-0 .mw-parser-output .sidebar{display:none!important}}</style><table class="sidebar sidebar-collapse nomobile nowraplinks"><tbody><tr><th class="sidebar-title"><a href="/wiki/Modern_physics" title="Modern physics">Modern physics</a></th></tr><tr><td class="sidebar-image"><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle {\hat {H}}|\psi _{n}(t)\rangle =i\hbar {\frac {d}{dt}}|\psi _{n}(t)\rangle }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi>H</mi> <mo stretchy="false">^</mo> </mover> </mrow> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mo stretchy="false">|</mo> </mrow> <msub> <mi>ψ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>n</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo fence="false" stretchy="false">⟩</mo> <mo>=</mo> <mi>i</mi> <mi class="MJX-variant">ℏ</mi> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mi>d</mi> <mrow> <mi>d</mi> <mi>t</mi> </mrow> </mfrac> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mo stretchy="false">|</mo> </mrow> <msub> <mi>ψ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>n</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>t</mi> <mo stretchy="false">)</mo> <mo fence="false" stretchy="false">⟩</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle {\hat {H}}|\psi _{n}(t)\rangle =i\hbar {\frac {d}{dt}}|\psi _{n}(t)\rangle }</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/6227214310d46ffac904ca257878eee1fb6ce726" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -2.005ex; width:24.027ex; height:5.509ex;" alt="{\displaystyle {\hat {H}}|\psi _{n}(t)\rangle =i\hbar {\frac {d}{dt}}|\psi _{n}(t)\rangle }"></span> <br /><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle G_{\mu \nu }+\Lambda g_{\mu \nu }={\kappa }T_{\mu \nu }}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>G</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>μ</mi> <mi>ν</mi> </mrow> </msub> <mo>+</mo> <mi mathvariant="normal">Λ</mi> <msub> <mi>g</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>μ</mi> <mi>ν</mi> </mrow> </msub> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mi>κ</mi> </mrow> <msub> <mi>T</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>μ</mi> <mi>ν</mi> </mrow> </msub> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle G_{\mu \nu }+\Lambda g_{\mu \nu }={\kappa }T_{\mu \nu }}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/124ab80fcb17e2733cc17ff6f93da5e52f355c77" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.005ex; width:19.468ex; height:2.843ex;" alt="{\displaystyle G_{\mu \nu }+\Lambda g_{\mu \nu }={\kappa }T_{\mu \nu }}"></span><div class="sidebar-caption" style="font-size:90%;padding-top:0.4em;font-style:italic;"><a href="/wiki/Schr%C3%B6dinger_equation" title="Schrödinger equation">Schrödinger</a> and <a href="/wiki/Einstein_field_equations" title="Einstein field equations">Einstein field equations</a></div></td></tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:transparent;border-top:1px solid #aaa;text-align:center;;color: var(--color-base)">Founders</div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Max_Planck" title="Max Planck">Max Planck</a></li> <li><a href="/wiki/Albert_Einstein" title="Albert Einstein">Albert Einstein</a></li> <li><a href="/wiki/Niels_Bohr" title="Niels Bohr">Niels Bohr</a></li> <li><a href="/wiki/Max_Born" title="Max Born">Max Born</a></li> <li><a href="/wiki/Erwin_Schr%C3%B6dinger" title="Erwin Schrödinger">Erwin Schrödinger</a></li> <li><a href="/wiki/Werner_Heisenberg" title="Werner Heisenberg">Werner Heisenberg</a></li> <li><a href="/wiki/Pascual_Jordan" title="Pascual Jordan">Pascual Jordan</a></li> <li><a href="/wiki/Wolfgang_Pauli" title="Wolfgang Pauli">Wolfgang Pauli</a></li> <li><a href="/wiki/Paul_Dirac" title="Paul Dirac">Paul Dirac</a></li> <li><a href="/wiki/Ernest_Rutherford" title="Ernest Rutherford">Ernest Rutherford</a></li> <li><a href="/wiki/Louis_de_Broglie" title="Louis de Broglie">Louis de Broglie</a></li> <li><a href="/wiki/Satyendra_Nath_Bose" title="Satyendra Nath Bose">Satyendra Nath Bose</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:transparent;border-top:1px solid #aaa;text-align:center;;color: var(--color-base)">Concepts</div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Spacetime_topology" title="Spacetime topology">Topology</a></li> <li><a href="/wiki/Space" title="Space">Space</a></li> <li><a href="/wiki/Time" title="Time">Time</a></li> <li><a href="/wiki/Energy" title="Energy">Energy</a></li> <li><a href="/wiki/Matter" title="Matter">Matter</a></li> <li><a href="/wiki/Work_(physics)" title="Work (physics)">Work</a></li> <li><a href="/wiki/Randomness" title="Randomness">Randomness</a></li> <li><a href="/wiki/Information" title="Information">Information</a></li> <li><a href="/wiki/Entropy" title="Entropy">Entropy</a></li> <li><a class="mw-selflink selflink">Light</a></li> <li><a href="/wiki/Particle" title="Particle">Particle</a></li> <li><a href="/wiki/Wave" title="Wave">Wave</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:transparent;border-top:1px solid #aaa;text-align:center;;color: var(--color-base)">Branches</div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Applied_physics" title="Applied physics">Applied</a></li> <li><a href="/wiki/Experimental_physics" title="Experimental physics">Experimental</a></li> <li><a href="/wiki/Theoretical_physics" title="Theoretical physics">Theoretical</a></li> <li><a href="/wiki/Mathematical_physics" title="Mathematical physics">Mathematical</a></li> <li><a href="/wiki/Philosophy_of_physics" title="Philosophy of physics">Philosophy of physics</a></li> <li><a href="/wiki/Quantum_mechanics" title="Quantum mechanics">Quantum mechanics</a> <ul><li><a href="/wiki/Quantum_field_theory" title="Quantum field theory">Quantum field theory</a></li> <li><a href="/wiki/Quantum_information" title="Quantum information">Quantum information</a></li> <li><a href="/wiki/Quantum_computation" class="mw-redirect" title="Quantum computation">Quantum computation</a></li></ul></li> <li><a href="/wiki/Electromagnetism" title="Electromagnetism">Electromagnetism</a></li> <li><a href="/wiki/Weak_interaction" title="Weak interaction">Weak interaction</a></li> <li><a href="/wiki/Electroweak_interaction" title="Electroweak interaction">Electroweak interaction</a></li> <li><a href="/wiki/Strong_interaction" title="Strong interaction">Strong interaction</a></li> <li><a href="/wiki/Atomic_physics" title="Atomic physics">Atomic</a></li> <li><a href="/wiki/Particle_physics" title="Particle physics">Particle</a></li> <li><a href="/wiki/Nuclear_physics" title="Nuclear physics">Nuclear</a></li> <li><a href="/wiki/Atomic,_molecular,_and_optical_physics" title="Atomic, molecular, and optical physics">Atomic, molecular, and optical</a></li> <li><a href="/wiki/Condensed_matter_physics" title="Condensed matter physics">Condensed matter</a></li> <li><a href="/wiki/Statistical_physics" class="mw-redirect" title="Statistical physics">Statistical</a></li> <li><a href="/wiki/Complex_system" title="Complex system">Complex systems</a></li> <li><a href="/wiki/Non-linear_dynamics" class="mw-redirect" title="Non-linear dynamics">Non-linear dynamics</a></li> <li><a href="/wiki/Biophysics" title="Biophysics">Biophysics</a></li> <li><a href="/wiki/Neurophysics" title="Neurophysics">Neurophysics</a></li> <li><a href="/wiki/Plasma_physics" class="mw-redirect" title="Plasma physics">Plasma physics</a></li> <li><a href="/wiki/Special_relativity" title="Special relativity">Special relativity</a></li> <li><a href="/wiki/General_relativity" title="General relativity">General relativity</a></li> <li><a href="/wiki/Astrophysics" title="Astrophysics">Astrophysics</a></li> <li><a href="/wiki/Cosmology" title="Cosmology">Cosmology</a></li> <li><a href="/wiki/Theories_of_gravitation" class="mw-redirect" title="Theories of gravitation">Theories of gravitation</a></li> <li><a href="/wiki/Quantum_gravity" title="Quantum gravity">Quantum gravity</a></li> <li><a href="/wiki/Theory_of_everything" title="Theory of everything">Theory of everything</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:transparent;border-top:1px solid #aaa;text-align:center;;color: var(--color-base)">Scientists</div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><a href="/wiki/Wilhelm_R%C3%B6ntgen" title="Wilhelm Röntgen">Röntgen</a></li> <li><a href="/wiki/Edward_Witten" title="Edward Witten">Witten</a></li> <li><a href="/wiki/Henri_Becquerel" title="Henri Becquerel">Becquerel</a></li> <li><a href="/wiki/Hendrik_Lorentz" title="Hendrik Lorentz">Lorentz</a></li> <li><a href="/wiki/Max_Planck" title="Max Planck">Planck</a></li> <li><a href="/wiki/Pierre_Curie" title="Pierre Curie">Curie</a></li> <li><a href="/wiki/Wilhelm_Wien" title="Wilhelm Wien">Wien</a></li> <li><a href="/wiki/Marie_Curie" title="Marie Curie">Skłodowska-Curie</a></li> <li><a href="/wiki/Arnold_Sommerfeld" title="Arnold Sommerfeld">Sommerfeld</a></li> <li><a href="/wiki/Ernest_Rutherford" title="Ernest Rutherford">Rutherford</a></li> <li><a href="/wiki/Frederick_Soddy" title="Frederick Soddy">Soddy</a></li> <li><a href="/wiki/Heike_Kamerlingh_Onnes" title="Heike Kamerlingh Onnes">Onnes</a></li> <li><a href="/wiki/Albert_Einstein" title="Albert Einstein">Einstein</a></li> <li><a href="/wiki/Frank_Wilczek" title="Frank Wilczek">Wilczek</a></li> <li><a href="/wiki/Max_Born" title="Max Born">Born</a></li> <li><a href="/wiki/Hermann_Weyl" title="Hermann Weyl">Weyl</a></li> <li><a href="/wiki/Niels_Bohr" title="Niels Bohr">Bohr</a></li> <li><a href="/wiki/Hendrik_Kramers" class="mw-redirect" title="Hendrik Kramers">Kramers</a></li> <li><a href="/wiki/Erwin_Schr%C3%B6dinger" title="Erwin Schrödinger">Schrödinger</a></li> <li><a href="/wiki/Louis_de_Broglie" title="Louis de Broglie">de Broglie</a></li> <li><a href="/wiki/Max_von_Laue" title="Max von Laue">Laue</a></li> <li><a href="/wiki/Satyendra_Nath_Bose" title="Satyendra Nath Bose">Bose</a></li> <li><a href="/wiki/Arthur_Compton" title="Arthur Compton">Compton</a></li> <li><a href="/wiki/Wolfgang_Pauli" title="Wolfgang Pauli">Pauli</a></li> <li><a href="/wiki/Ernest_Walton" title="Ernest Walton">Walton</a></li> <li><a href="/wiki/Enrico_Fermi" title="Enrico Fermi">Fermi</a></li> <li><a href="/wiki/Johannes_Diderik_van_der_Waals" title="Johannes Diderik van der Waals">van der Waals</a></li> <li><a href="/wiki/Werner_Heisenberg" title="Werner Heisenberg">Heisenberg</a></li> <li><a href="/wiki/Freeman_Dyson" title="Freeman Dyson">Dyson</a></li> <li><a href="/wiki/Pieter_Zeeman" title="Pieter Zeeman">Zeeman</a></li> <li><a href="/wiki/Henry_Moseley" title="Henry Moseley">Moseley</a></li> <li><a href="/wiki/David_Hilbert" title="David Hilbert">Hilbert</a></li> <li><a href="/wiki/Kurt_G%C3%B6del" title="Kurt Gödel">Gödel</a></li> <li><a href="/wiki/Pascual_Jordan" title="Pascual Jordan">Jordan</a></li> <li><a href="/wiki/Paul_Dirac" title="Paul Dirac">Dirac</a></li> <li><a href="/wiki/Eugene_Wigner" title="Eugene Wigner">Wigner</a></li> <li><a href="/wiki/Stephen_Hawking" title="Stephen Hawking">Hawking</a></li> <li><a href="/wiki/Philip_Warren_Anderson" class="mw-redirect" title="Philip Warren Anderson">P. W. Anderson</a></li> <li><a href="/wiki/Georges_Lema%C3%AEtre" title="Georges Lemaître">Lemaître</a></li> <li><a href="/wiki/Sir_George_Paget_Thomson" class="mw-redirect" title="Sir George Paget Thomson">Thomson</a></li> <li><a href="/wiki/Henri_Poincar%C3%A9" title="Henri Poincaré">Poincaré</a></li> <li><a href="/wiki/John_Archibald_Wheeler" title="John Archibald Wheeler">Wheeler</a></li> <li><a href="/wiki/Roger_Penrose" title="Roger Penrose">Penrose</a></li> <li><a href="/wiki/Robert_A._Millikan" class="mw-redirect" title="Robert A. Millikan">Millikan</a></li> <li><a href="/wiki/Yoichiro_Nambu" title="Yoichiro Nambu">Nambu</a></li> <li><a href="/wiki/John_von_Neumann" title="John von Neumann">von Neumann</a></li> <li><a href="/wiki/Peter_Higgs" title="Peter Higgs">Higgs</a></li> <li><a href="/wiki/Otto_Hahn" title="Otto Hahn">Hahn</a></li> <li><a href="/wiki/Richard_Feynman" title="Richard Feynman">Feynman</a></li> <li><a href="/wiki/Yang_Chen-Ning" title="Yang Chen-Ning">Yang</a></li> <li><a href="/wiki/Tsung-Dao_Lee" title="Tsung-Dao Lee">Lee</a></li> <li><a href="/wiki/Philipp_Lenard" title="Philipp Lenard">Lenard</a></li> <li><a href="/wiki/Abdus_Salam" title="Abdus Salam">Salam</a></li> <li><a href="/wiki/Gerard_%27t_Hooft" title="Gerard 't Hooft">'t Hooft</a></li> <li><a href="/wiki/Martinus_Veltman" class="mw-redirect" title="Martinus Veltman">Veltman</a></li> <li><a href="/wiki/John_Stewart_Bell" title="John Stewart Bell">Bell</a></li> <li><a href="/wiki/Murray_Gell-Mann" title="Murray Gell-Mann">Gell-Mann</a></li> <li><a href="/wiki/J._J._Thomson" title="J. J. Thomson">J. J. Thomson</a></li> <li><a href="/wiki/C._V._Raman" title="C. V. Raman">Raman</a></li> <li><a href="/wiki/Lawrence_Bragg" title="Lawrence Bragg">Bragg</a></li> <li><a href="/wiki/John_Bardeen" title="John Bardeen">Bardeen</a></li> <li><a href="/wiki/William_Shockley" title="William Shockley">Shockley</a></li> <li><a href="/wiki/James_Chadwick" title="James Chadwick">Chadwick</a></li> <li><a href="/wiki/Ernest_O._Lawrence" class="mw-redirect" title="Ernest O. Lawrence">Lawrence</a></li> <li><a href="/wiki/Anton_Zeilinger" title="Anton Zeilinger">Zeilinger</a></li> <li><a href="/wiki/Samuel_Goudsmit" title="Samuel Goudsmit">Goudsmit</a></li> <li><a href="/wiki/George_Uhlenbeck" title="George Uhlenbeck">Uhlenbeck</a></li></ul></div></div></td> </tr><tr><td class="sidebar-content"> <div class="sidebar-list mw-collapsible mw-collapsed"><div class="sidebar-list-title" style="background:transparent;border-top:1px solid #aaa;text-align:center;;color: var(--color-base)">Categories</div><div class="sidebar-list-content mw-collapsible-content hlist"> <ul><li><div class="CategoryTreeTag" data-ct-options="{"mode":0,"hideprefix":20,"showcount":false,"namespaces":false,"notranslations":false}"><div class="CategoryTreeSection"><div class="CategoryTreeItem"><span class="CategoryTreeEmptyBullet"></span> <bdi dir="ltr"><a href="/wiki/Category:Modern_physics" title="Category:Modern physics">Modern physics</a></bdi></div><div class="CategoryTreeChildren" style="display:none"></div></div></div></li></ul></div></div></td> </tr><tr><td class="sidebar-navbar"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Modern_physics" title="Template:Modern physics"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Modern_physics" title="Template talk:Modern physics"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Modern_physics" title="Special:EditPage/Template:Modern physics"><abbr title="Edit this template">e</abbr></a></li></ul></div></td></tr></tbody></table> <p><b>Light</b>, <b>visible light</b>, or <b>visible radiation</b> is <a href="/wiki/Electromagnetic_radiation" title="Electromagnetic radiation">electromagnetic radiation</a> that can be <a href="/wiki/Visual_perception" title="Visual perception">perceived</a> by the <a href="/wiki/Human_eye" title="Human eye">human eye</a>.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Visible light spans the <a href="/wiki/Visible_spectrum" title="Visible spectrum">visible spectrum</a> and is usually defined as having <a href="/wiki/Wavelength" title="Wavelength">wavelengths</a> in the range of 400–700 <a href="/wiki/Nanometre" title="Nanometre">nanometres</a> (nm), corresponding to <a href="/wiki/Frequency" title="Frequency">frequencies</a> of 750–420 <a href="/wiki/Terahertz_(unit)" class="mw-redirect" title="Terahertz (unit)">terahertz</a>. The visible band sits adjacent to the <a href="/wiki/Infrared" title="Infrared">infrared</a> (with longer wavelengths and lower frequencies) and the <a href="/wiki/Ultraviolet" title="Ultraviolet">ultraviolet</a> (with shorter wavelengths and higher frequencies), called collectively <i><a href="/wiki/Optical_radiation" title="Optical radiation">optical radiation</a></i>.<sup id="cite_ref-Pal2001_2-0" class="reference"><a href="#cite_note-Pal2001-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-BuserImbert1992_3-0" class="reference"><a href="#cite_note-BuserImbert1992-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p><p>In <a href="/wiki/Physics" title="Physics">physics</a>, the term "light" may refer more broadly to electromagnetic radiation of any wavelength, whether visible or not.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> In this sense, <a href="/wiki/Gamma_ray" title="Gamma ray">gamma rays</a>, <a href="/wiki/X-ray" title="X-ray">X-rays</a>, <a href="/wiki/Microwave" title="Microwave">microwaves</a> and <a href="/wiki/Radio_wave" title="Radio wave">radio waves</a> are also light. The primary properties of light are <a href="/wiki/Intensity_(physics)" title="Intensity (physics)">intensity</a>, propagation direction, frequency or wavelength <a href="/wiki/Spectrum" title="Spectrum">spectrum</a>, and <a href="/wiki/Polarization_(waves)" title="Polarization (waves)">polarization</a>. Its <a href="/wiki/Speed_of_light" title="Speed of light">speed in vacuum</a>, <span class="nowrap"><span data-sort-value="7008299792458000000♠"></span>299<span style="margin-left:.25em;">792</span><span style="margin-left:.25em;">458</span> m/s</span>, is one of the fundamental <a href="/wiki/Physical_constant" title="Physical constant">constants</a> of nature.<sup id="cite_ref-LeClerq_6-0" class="reference"><a href="#cite_note-LeClerq-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Like all types of electromagnetic radiation, visible light propagates by massless elementary particles called <a href="/wiki/Photon" title="Photon">photons</a> that represents the <a href="/wiki/Quantum" title="Quantum">quanta</a> of electromagnetic field, and can be analyzed as both <a href="/wiki/Wave%E2%80%93particle_duality" title="Wave–particle duality">waves and particles</a>. The study of light, known as <a href="/wiki/Optics" title="Optics">optics</a>, is an important research area in <a href="/wiki/Modern_physics" title="Modern physics">modern physics</a>. </p><p>The main source of natural light on Earth is the <a href="/wiki/Sun" title="Sun">Sun</a>. Historically, another important source of light for humans has been <a href="/wiki/Fire" title="Fire">fire</a>, from ancient campfires to modern <a href="/wiki/Kerosene_lamp" title="Kerosene lamp">kerosene lamps</a>. With the development of <a href="/wiki/Electric_light" title="Electric light">electric lights</a> and <a href="/wiki/History_of_electric_power_transmission" title="History of electric power transmission">power systems</a>, electric lighting has effectively replaced firelight. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Electromagnetic_spectrum_and_visible_light">Electromagnetic spectrum and visible light</h2></div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:EM_spectrum.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f1/EM_spectrum.svg/380px-EM_spectrum.svg.png" decoding="async" width="380" height="180" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f1/EM_spectrum.svg/570px-EM_spectrum.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f1/EM_spectrum.svg/760px-EM_spectrum.svg.png 2x" data-file-width="788" data-file-height="374" /></a><figcaption>The <a href="/wiki/Electromagnetic_spectrum" title="Electromagnetic spectrum">electromagnetic spectrum</a>, with the <a href="/wiki/Visible_spectrum" title="Visible spectrum">visible portion</a> highlighted. The bottom graph (Visible spectrum) is wavelength in units of nanometres (nm).</figcaption></figure> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Electromagnetic_spectrum" title="Electromagnetic spectrum">Electromagnetic spectrum</a></div> <p>Generally, <a href="/wiki/Electromagnetic_radiation" title="Electromagnetic radiation">electromagnetic radiation</a> (EMR) is classified by wavelength into <a href="/wiki/Radio_wave" title="Radio wave">radio waves</a>, <a href="/wiki/Microwave" title="Microwave">microwaves</a>, <a href="/wiki/Infrared" title="Infrared">infrared</a>, the <a href="/wiki/Visible_spectrum" title="Visible spectrum">visible spectrum</a> that we perceive as light, <a href="/wiki/Ultraviolet" title="Ultraviolet">ultraviolet</a>, <a href="/wiki/X-ray" title="X-ray">X-rays</a> and <a href="/wiki/Gamma_ray" title="Gamma ray">gamma rays</a>. The designation "<a href="/wiki/Radiation" title="Radiation">radiation</a>" excludes <a href="/wiki/Static_electricity" title="Static electricity">static electric</a>, <a href="/wiki/Magnetic_field" title="Magnetic field">magnetic</a> and <a href="/wiki/Near_and_far_field" title="Near and far field">near fields</a>. </p><p>The behavior of EMR depends on its wavelength. Higher frequencies have shorter wavelengths and lower frequencies have longer wavelengths. When EMR interacts with single atoms and molecules, its behavior depends on the amount of energy per quantum it carries. </p><p>EMR in the visible light region consists of <a href="/wiki/Quantum" title="Quantum">quanta</a> (called <a href="/wiki/Photon" title="Photon">photons</a>) that are at the lower end of the energies that are capable of causing electronic excitation within molecules, which leads to changes in the bonding or chemistry of the molecule. At the lower end of the visible light spectrum, EMR becomes invisible to humans (infrared) because its photons no longer have enough individual energy to cause a lasting molecular change (a change in conformation) in the visual molecule <a href="/wiki/Retinal" title="Retinal">retinal</a> in the human retina, which change triggers the sensation of vision. </p><p>There exist animals that are sensitive to various types of infrared, but not by means of quantum-absorption. <a href="/wiki/Infrared_sensing_in_snakes" title="Infrared sensing in snakes">Infrared sensing in snakes</a> depends on a kind of natural <a href="/wiki/Thermal_imaging" class="mw-redirect" title="Thermal imaging">thermal imaging</a>, in which tiny packets of cellular water are raised in temperature by the infrared radiation. EMR in this range causes molecular vibration and heating effects, which is how these animals detect it. </p><p>Above the range of visible light, ultraviolet light becomes invisible to humans, mostly because it is absorbed by the cornea below 360 <a href="/wiki/Nanometer" class="mw-redirect" title="Nanometer">nm</a> and the internal lens below 400 nm. Furthermore, the <a href="/wiki/Rod_cell" title="Rod cell">rods</a> and <a href="/wiki/Cone_cell" title="Cone cell">cones</a> located in the <a href="/wiki/Retina" title="Retina">retina</a> of the human eye cannot detect the very short (below 360 nm) ultraviolet wavelengths and are in fact damaged by ultraviolet. Many animals with eyes that do not require lenses (such as insects and shrimp) are able to detect ultraviolet, by quantum photon-absorption mechanisms, in much the same chemical way that humans detect visible light. </p><p>Various sources define visible light as narrowly as 420–680 nm<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Bradt2004_8-0" class="reference"><a href="#cite_note-Bradt2004-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> to as broadly as 380–800 nm.<sup id="cite_ref-OhannesianStreeter2001_9-0" class="reference"><a href="#cite_note-OhannesianStreeter2001-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-AhluwaliaGoyal2000_10-0" class="reference"><a href="#cite_note-AhluwaliaGoyal2000-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Under ideal laboratory conditions, people can see infrared up to at least 1,050 nm;<sup id="cite_ref-Sliney1976_11-0" class="reference"><a href="#cite_note-Sliney1976-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> children and young adults may perceive ultraviolet wavelengths down to about 310–313 nm.<sup id="cite_ref-LynchLivingston2001_12-0" class="reference"><a href="#cite_note-LynchLivingston2001-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Dash2009_13-0" class="reference"><a href="#cite_note-Dash2009-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Saidman1933_14-0" class="reference"><a href="#cite_note-Saidman1933-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p><p>Plant growth is also affected by the colour spectrum of light, a process known as <a href="/wiki/Photomorphogenesis" title="Photomorphogenesis">photomorphogenesis</a>. </p> <div class="mw-heading mw-heading2"><h2 id="Speed_of_light">Speed of light</h2></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Speed_of_light" title="Speed of light">Speed of light</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Rocca_dell%27Abisso,_Fondachelli_Fantina,_Sicilia.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Rocca_dell%27Abisso%2C_Fondachelli_Fantina%2C_Sicilia.JPG/220px-Rocca_dell%27Abisso%2C_Fondachelli_Fantina%2C_Sicilia.JPG" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Rocca_dell%27Abisso%2C_Fondachelli_Fantina%2C_Sicilia.JPG/330px-Rocca_dell%27Abisso%2C_Fondachelli_Fantina%2C_Sicilia.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/ba/Rocca_dell%27Abisso%2C_Fondachelli_Fantina%2C_Sicilia.JPG/440px-Rocca_dell%27Abisso%2C_Fondachelli_Fantina%2C_Sicilia.JPG 2x" data-file-width="2272" data-file-height="1704" /></a><figcaption>Beam of sun light inside the cavity of Rocca ill'Abissu at <a href="/wiki/Fondachelli-Fantina" title="Fondachelli-Fantina">Fondachelli-Fantina</a>, Sicily</figcaption></figure> <p>The speed of light in <a href="/wiki/Vacuum" title="Vacuum">vacuum</a> is defined to be exactly <span class="nowrap"><span data-sort-value="7008299792458000000♠"></span>299<span style="margin-left:.25em;">792</span><span style="margin-left:.25em;">458</span> m/s</span> (approximately 186,282 miles per second). The fixed value of the speed of light in SI units results from the fact that the metre is now defined in terms of the speed of light. All forms of electromagnetic radiation move at exactly this same speed in vacuum. </p><p>Different <a href="/wiki/Physicist" title="Physicist">physicists</a> have attempted to measure the speed of light throughout history. <a href="/wiki/Galileo_Galilei" title="Galileo Galilei">Galileo</a> attempted to measure the speed of light in the seventeenth century. An early experiment to measure the speed of light was conducted by <a href="/wiki/Ole_R%C3%B8mer" title="Ole Rømer">Ole Rømer</a>, a Danish physicist, in 1676. Using a <a href="/wiki/Telescope" title="Telescope">telescope</a>, Rømer observed the motions of <a href="/wiki/Jupiter" title="Jupiter">Jupiter</a> and one of its <a href="/wiki/Natural_satellite" title="Natural satellite">moons</a>, <a href="/wiki/Io_(moon)" title="Io (moon)">Io</a>. Noting discrepancies in the apparent period of Io's orbit, he calculated that light takes about 22 minutes to traverse the diameter of Earth's orbit.<sup id="cite_ref-15" class="reference"><a href="#cite_note-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> However, its size was not known at that time. If Rømer had known the diameter of the Earth's orbit, he would have calculated a speed of <span class="nowrap"><span data-sort-value="7008227000000000000♠"></span>227<span style="margin-left:.25em;">000</span><span style="margin-left:.25em;">000</span> m/s</span>. </p><p>Another more accurate measurement of the speed of light was performed in Europe by <a href="/wiki/Hippolyte_Fizeau" title="Hippolyte Fizeau">Hippolyte Fizeau</a> in 1849.<sup id="cite_ref-EB1911_16-0" class="reference"><a href="#cite_note-EB1911-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> Fizeau directed a beam of light at a mirror several kilometers away. A rotating <a href="/wiki/Cog_wheel" class="mw-redirect" title="Cog wheel">cog wheel</a> was placed in the path of the light beam as it traveled from the source, to the mirror and then returned to its origin. Fizeau found that at a certain rate of rotation, the beam would pass through one gap in the wheel on the way out and the next gap on the way back. Knowing the distance to the mirror, the number of teeth on the wheel and the rate of rotation, Fizeau was able to calculate the speed of light as <span class="nowrap"><span data-sort-value="7008313000000000000♠"></span>313<span style="margin-left:.25em;">000</span><span style="margin-left:.25em;">000</span> m/s</span>. </p><p><a href="/wiki/L%C3%A9on_Foucault" title="Léon Foucault">Léon Foucault</a> carried out an experiment which used rotating mirrors to obtain a value of <span class="nowrap"><span data-sort-value="7008298000000000000♠"></span>298<span style="margin-left:.25em;">000</span><span style="margin-left:.25em;">000</span> m/s</span><sup id="cite_ref-EB1911_16-1" class="reference"><a href="#cite_note-EB1911-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> in 1862. <a href="/wiki/Albert_A._Michelson" title="Albert A. Michelson">Albert A. Michelson</a> conducted experiments on the speed of light from 1877 until his death in 1931. He refined Foucault's methods in 1926 using improved rotating mirrors to measure the time it took light to make a round trip from <a href="/wiki/Mount_Wilson_(California)" title="Mount Wilson (California)">Mount Wilson</a> to <a href="/wiki/Mount_San_Antonio" title="Mount San Antonio">Mount San Antonio</a> in California. The precise measurements yielded a speed of <span class="nowrap"><span data-sort-value="7008299796000000000♠"></span>299<span style="margin-left:.25em;">796</span><span style="margin-left:.25em;">000</span> m/s</span>.<sup id="cite_ref-17" class="reference"><a href="#cite_note-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> </p><p>The effective velocity of light in various transparent substances containing ordinary <a href="/wiki/Matter" title="Matter">matter</a>, is less than in vacuum. For example, the speed of light in water is about 3/4 of that in vacuum. </p><p>Two independent teams of physicists were said to bring light to a "complete standstill" by passing it through a <a href="/wiki/Bose%E2%80%93Einstein_condensate" title="Bose–Einstein condensate">Bose–Einstein condensate</a> of the element <a href="/wiki/Rubidium" title="Rubidium">rubidium</a>, one team at <a href="/wiki/Harvard_University" title="Harvard University">Harvard University</a> and the <a href="/wiki/Rowland_Institute_for_Science" class="mw-redirect" title="Rowland Institute for Science">Rowland Institute for Science</a> in Cambridge, Massachusetts and the other at the <a href="/wiki/Harvard%E2%80%93Smithsonian_Center_for_Astrophysics" title="Harvard–Smithsonian Center for Astrophysics">Harvard–Smithsonian Center for Astrophysics</a>, also in Cambridge.<sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> However, the popular description of light being "stopped" in these experiments refers only to light being stored in the excited states of atoms, then re-emitted at an arbitrary later time, as stimulated by a second laser pulse. During the time it had "stopped", it had ceased to be light. </p> <div class="mw-heading mw-heading2"><h2 id="Optics">Optics</h2></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Optics" title="Optics">Optics</a></div> <figure class="mw-default-size mw-halign-center" typeof="mw:File"><a href="/wiki/File:Linear_visible_spectrum.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Linear_visible_spectrum.svg/605px-Linear_visible_spectrum.svg.png" decoding="async" width="605" height="115" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Linear_visible_spectrum.svg/908px-Linear_visible_spectrum.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/d9/Linear_visible_spectrum.svg/1210px-Linear_visible_spectrum.svg.png 2x" data-file-width="605" data-file-height="115" /></a><figcaption></figcaption></figure> <p>The study of light and the interaction of light and <a href="/wiki/Matter" title="Matter">matter</a> is termed <i><a href="/wiki/Optics" title="Optics">optics</a></i>. The observation and study of <a href="/wiki/Optical_phenomena" class="mw-redirect" title="Optical phenomena">optical phenomena</a> such as <a href="/wiki/Rainbow" title="Rainbow">rainbows</a> and the <a href="/wiki/Aurora_(astronomy)" class="mw-redirect" title="Aurora (astronomy)">aurora borealis</a> offer many clues as to the nature of light. </p><p>A <a href="/wiki/Transparency_(optics)" class="mw-redirect" title="Transparency (optics)">transparent</a> object allows light to <a href="/wiki/Transmittance" title="Transmittance">transmit</a> or pass through. Conversely, an <a href="/wiki/Opacity_(optics)" class="mw-redirect" title="Opacity (optics)">opaque</a> object does not allow light to transmit through and instead <a href="/wiki/Reflection_(physics)" title="Reflection (physics)">reflecting</a> or <a href="/wiki/Absorbance" title="Absorbance">absorbing</a> the light it receives. Most objects do not reflect or transmit light <a href="/wiki/Specular_reflection" title="Specular reflection">specularly</a> and to some degree <a href="/wiki/Scattering" title="Scattering">scatters</a> the incoming light, which is called <a href="/wiki/Gloss_(optics)" title="Gloss (optics)">glossiness</a>. Surface scatterance is caused by the <a href="/wiki/Surface_roughness" title="Surface roughness">surface roughness</a> of the reflecting surfaces, and internal scatterance is caused by the difference of <a href="/wiki/Refractive_index" title="Refractive index">refractive index</a> between the particles and <a href="/wiki/Transmission_medium" title="Transmission medium">medium</a> inside the object. Like transparent objects, <a href="/wiki/Translucent" class="mw-redirect" title="Translucent">translucent</a> objects allow light to transmit through, but translucent objects also scatter certain wavelength of light via internal scatterance.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Refraction">Refraction</h3></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Refraction" title="Refraction">Refraction</a></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Optical_refraction_at_water_surface.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Optical_refraction_at_water_surface.jpg/220px-Optical_refraction_at_water_surface.jpg" decoding="async" width="220" height="187" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Optical_refraction_at_water_surface.jpg/330px-Optical_refraction_at_water_surface.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Optical_refraction_at_water_surface.jpg/440px-Optical_refraction_at_water_surface.jpg 2x" data-file-width="775" data-file-height="658" /></a><figcaption>Due to refraction, the straw dipped in water appears bent and the ruler scale compressed when viewed from a shallow angle.</figcaption></figure> <p>Refraction is the bending of light rays when passing through a surface between one transparent material and another. It is described by <a href="/wiki/Snell%27s_Law" class="mw-redirect" title="Snell's Law">Snell's Law</a>: </p> <dl><dd><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n_{1}\sin \theta _{1}=n_{2}\sin \theta _{2}\ .}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mi>sin</mi> <mo>⁡</mo> <msub> <mi>θ</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>1</mn> </mrow> </msub> <mo>=</mo> <msub> <mi>n</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mi>sin</mi> <mo>⁡</mo> <msub> <mi>θ</mi> <mrow class="MJX-TeXAtom-ORD"> <mn>2</mn> </mrow> </msub> <mtext> </mtext> <mo>.</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n_{1}\sin \theta _{1}=n_{2}\sin \theta _{2}\ .}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/398f655ab547c613f8614a2b6264096c9b631360" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:20.773ex; height:2.509ex;" alt="{\displaystyle n_{1}\sin \theta _{1}=n_{2}\sin \theta _{2}\ .}"></span></dd></dl> <p>where θ<sub>1</sub> is the angle between the ray and the surface <a href="/wiki/Normal_(geometry)" title="Normal (geometry)">normal</a> in the first medium, θ<sub>2</sub> is the angle between the ray and the surface normal in the second medium and n<sub>1</sub> and n<sub>2</sub> are the <a href="/wiki/Index_of_refraction" class="mw-redirect" title="Index of refraction">indices of refraction</a>, <i>n</i> = 1 in a <a href="/wiki/Vacuum" title="Vacuum">vacuum</a> and <i>n</i> > 1 in a <a href="/wiki/Transparency_and_translucency" title="Transparency and translucency">transparent</a> <a href="/wiki/Chemical_substance" title="Chemical substance">substance</a>. </p><p>When a beam of light crosses the boundary between a vacuum and another medium, or between two different media, the wavelength of the light changes, but the frequency remains constant. If the beam of light is not <a href="/wiki/Orthogonality" title="Orthogonality">orthogonal</a> (or rather normal) to the boundary, the change in wavelength results in a change in the direction of the beam. This change of direction is known as <a href="/wiki/Refraction" title="Refraction">refraction</a>. </p><p>The refractive quality of <a href="/wiki/Lens_(optics)" class="mw-redirect" title="Lens (optics)">lenses</a> is frequently used to manipulate light in order to change the apparent size of images. <a href="/wiki/Magnifying_glass" title="Magnifying glass">Magnifying glasses</a>, <a href="/wiki/Glasses" title="Glasses">spectacles</a>, <a href="/wiki/Contact_lens" title="Contact lens">contact lenses</a>, <a href="/wiki/Microscope" title="Microscope">microscopes</a> and <a href="/wiki/Refracting_telescope" title="Refracting telescope">refracting telescopes</a> are all examples of this manipulation. </p> <div class="mw-heading mw-heading2"><h2 id="Light_sources">Light sources</h2></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">"Lightsource" redirects here. For the solar energy developer named Lightsource, see <a href="/wiki/Lightsource_Renewable_Energy" class="mw-redirect" title="Lightsource Renewable Energy">Lightsource Renewable Energy</a>. For a particle accelerator used to generate X-rays, see <a href="/wiki/Synchrotron_light_source" title="Synchrotron light source">Synchrotron light source</a>.</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="/wiki/List_of_light_sources" title="List of light sources">List of light sources</a></div> <p>There are many sources of light. A body at a given temperature emits a characteristic spectrum of <a href="/wiki/Black-body_radiation" title="Black-body radiation">black-body radiation</a>. A simple thermal source is <a href="/wiki/Sunlight" title="Sunlight">sunlight</a>, the radiation emitted by the <a href="/wiki/Chromosphere" title="Chromosphere">chromosphere</a> of the <a href="/wiki/Sun" title="Sun">Sun</a> at around 6,000 <a href="/wiki/Kelvin" title="Kelvin">K</a> (5,730 <a href="/wiki/Celsius" title="Celsius">°C</a>; 10,340 <a href="/wiki/Fahrenheit" title="Fahrenheit">°F</a>). Solar radiation peaks in the visible region of the <a href="/wiki/Electromagnetic_spectrum" title="Electromagnetic spectrum">electromagnetic spectrum</a> when plotted in wavelength units,<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> and roughly 44% of the radiation that reaches the ground is visible.<sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> Another example is <a href="/wiki/Incandescent_light_bulb" title="Incandescent light bulb">incandescent light bulbs</a>, which emit only around 10% of their energy as visible light and the remainder as infrared. A common thermal light source in history is the glowing solid particles in <a href="/wiki/Fire" title="Fire">flames</a>, but these also emit most of their radiation in the infrared and only a fraction in the visible spectrum. </p><p>The peak of the black-body spectrum is in the deep infrared, at about 10 <a href="/wiki/Micrometre" title="Micrometre">micrometre</a> wavelength, for relatively cool objects like human beings. As the temperature increases, the peak shifts to shorter wavelengths, producing first a red glow, then a white one and finally a blue-white colour as the peak moves out of the visible part of the spectrum and into the ultraviolet. These colours can be seen when metal is heated to "red hot" or "white hot". Blue-white <a href="/wiki/Thermal_emission" class="mw-redirect" title="Thermal emission">thermal emission</a> is not often seen, except in stars (the commonly seen pure-blue colour in a <a href="/wiki/Natural_gas" title="Natural gas">gas</a> flame or a <a href="/wiki/Welder" title="Welder">welder</a>'s torch is in fact due to molecular emission, notably by CH radicals emitting a wavelength band around 425 nm and is not seen in stars or pure thermal radiation). </p><p>Atoms emit and absorb light at characteristic energies. This produces "<a href="/wiki/Emission_line" class="mw-redirect" title="Emission line">emission lines</a>" in the spectrum of each atom. <a href="/wiki/Emission_(electromagnetic_radiation)" class="mw-redirect" title="Emission (electromagnetic radiation)">Emission</a> can be <a href="/wiki/Spontaneous_emission" title="Spontaneous emission">spontaneous</a>, as in <a href="/wiki/Light-emitting_diode" title="Light-emitting diode">light-emitting diodes</a>, <a href="/wiki/Gas_discharge" class="mw-redirect" title="Gas discharge">gas discharge</a> lamps (such as <a href="/wiki/Neon_lamp" title="Neon lamp">neon lamps</a> and <a href="/wiki/Neon_sign" title="Neon sign">neon signs</a>, <a href="/wiki/Mercury-vapor_lamp" title="Mercury-vapor lamp">mercury-vapor lamps</a>, etc.) and flames (light from the hot gas itself—so, for example, <a href="/wiki/Sodium" title="Sodium">sodium</a> in a gas flame emits characteristic yellow light). Emission can also be <a href="/wiki/Stimulated_emission" title="Stimulated emission">stimulated</a>, as in a <a href="/wiki/Laser" title="Laser">laser</a> or a microwave <a href="/wiki/Maser" title="Maser">maser</a>. </p><p>Deceleration of a free charged particle, such as an <a href="/wiki/Electron" title="Electron">electron</a>, can produce visible radiation: <a href="/wiki/Cyclotron_radiation" title="Cyclotron radiation">cyclotron radiation</a>, <a href="/wiki/Synchrotron_radiation" title="Synchrotron radiation">synchrotron radiation</a> and <a href="/wiki/Bremsstrahlung" title="Bremsstrahlung">bremsstrahlung</a> radiation are all examples of this. Particles moving through a medium faster than the speed of light in that medium can produce visible <a href="/wiki/Cherenkov_radiation" title="Cherenkov radiation">Cherenkov radiation</a>. Certain chemicals produce visible radiation by <a href="/wiki/Chemoluminescence" class="mw-redirect" title="Chemoluminescence">chemoluminescence</a>. In living things, this process is called <a href="/wiki/Bioluminescence" title="Bioluminescence">bioluminescence</a>. For example, <a href="/wiki/Firefly" title="Firefly">fireflies</a> produce light by this means and boats moving through water can disturb plankton which produce a glowing wake. </p><p>Certain substances produce light when they are illuminated by more energetic radiation, a process known as <a href="/wiki/Fluorescence" title="Fluorescence">fluorescence</a>. Some substances emit light slowly after excitation by more energetic radiation. This is known as <a href="/wiki/Phosphorescence" title="Phosphorescence">phosphorescence</a>. Phosphorescent materials can also be excited by bombarding them with subatomic particles. <a href="/wiki/Cathodoluminescence" title="Cathodoluminescence">Cathodoluminescence</a> is one example. This mechanism is used in <a href="/wiki/Cathode-ray_tube" title="Cathode-ray tube">cathode-ray tube</a> <a href="/wiki/Television_set" title="Television set">television sets</a> and <a href="/wiki/Computer_monitor" title="Computer monitor">computer monitors</a>. </p> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Colorful_artificial_lighting_at_night.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/7/70/Colorful_artificial_lighting_at_night.jpg/250px-Colorful_artificial_lighting_at_night.jpg" decoding="async" width="250" height="156" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/70/Colorful_artificial_lighting_at_night.jpg/375px-Colorful_artificial_lighting_at_night.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/70/Colorful_artificial_lighting_at_night.jpg/500px-Colorful_artificial_lighting_at_night.jpg 2x" data-file-width="640" data-file-height="400" /></a><figcaption><a href="/wiki/Hong_Kong" title="Hong Kong">Hong Kong</a> illuminated by colourful artificial <a href="/wiki/Lighting" title="Lighting">lighting</a></figcaption></figure> <p>Certain other mechanisms can produce light: </p> <ul><li><a href="/wiki/Electroluminescence" title="Electroluminescence">Electroluminescence</a></li> <li><a href="/wiki/Scintillation_(physics)" title="Scintillation (physics)">Scintillation</a></li> <li><a href="/wiki/Sonoluminescence" title="Sonoluminescence">Sonoluminescence</a></li> <li><a href="/wiki/Triboluminescence" title="Triboluminescence">Triboluminescence</a></li></ul> <p>When the concept of light is intended to include very-high-energy photons (gamma rays), additional generation mechanisms include: </p> <ul><li>Particle–<a href="/wiki/Antiparticle" title="Antiparticle">antiparticle</a> annihilation</li> <li><a href="/wiki/Radioactive_decay" title="Radioactive decay">Radioactive decay</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Measurement">Measurement</h2></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main articles: <a href="/wiki/Photometry_(optics)" title="Photometry (optics)">Photometry (optics)</a> and <a href="/wiki/Radiometry" title="Radiometry">Radiometry</a></div> <p>Light is measured with two main alternative sets of units: <a href="/wiki/Radiometry" title="Radiometry">radiometry</a> consists of measurements of light power at all wavelengths, while <a href="/wiki/Photometry_(optics)" title="Photometry (optics)">photometry</a> measures light with wavelength weighted with respect to a standardized model of human brightness perception. Photometry is useful, for example, to quantify <a href="/wiki/Illumination_(lighting)" class="mw-redirect" title="Illumination (lighting)">Illumination (lighting)</a> intended for human use. </p><p>The photometry units are different from most systems of physical units in that they take into account how the human eye responds to light. The <a href="/wiki/Cone_cell" title="Cone cell">cone cells</a> in the human eye are of three types which respond differently across the visible spectrum and the cumulative response peaks at a wavelength of around 555 nm. Therefore, two sources of light which produce the same intensity (W/m<sup>2</sup>) of visible light do not necessarily appear equally bright. The photometry units are designed to take this into account and therefore are a better representation of how "bright" a light appears to be than raw intensity. They relate to raw <a href="/wiki/Power_(physics)" title="Power (physics)">power</a> by a quantity called <a href="/wiki/Luminous_efficacy" title="Luminous efficacy">luminous efficacy</a> and are used for purposes like determining how to best achieve sufficient illumination for various tasks in indoor and outdoor settings. The illumination measured by a <a href="/wiki/Photocell" class="mw-redirect" title="Photocell">photocell</a> sensor does not necessarily correspond to what is perceived by the human eye and without filters which may be costly, photocells and <a href="/wiki/Charge-coupled_device" title="Charge-coupled device">charge-coupled devices</a> (CCD) tend to respond to some <a href="/wiki/Infrared" title="Infrared">infrared</a>, <a href="/wiki/Ultraviolet" title="Ultraviolet">ultraviolet</a> or both. </p> <div class="mw-heading mw-heading2"><h2 id="Light_pressure">Light pressure</h2></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Radiation_pressure" title="Radiation pressure">Radiation pressure</a></div> <p>Light exerts physical pressure on objects in its path, a phenomenon which can be deduced by <a href="/wiki/Maxwell%27s_equations" title="Maxwell's equations">Maxwell's equations</a>, but can be more easily explained by the particle nature of light: photons strike and transfer their momentum. Light pressure is equal to the power of the light beam divided by <i><a href="/wiki/Speed_of_light" title="Speed of light">c</a></i>, the speed of light.<span class="nowrap"> </span> Due to the magnitude of <i>c</i>, the effect of light pressure is negligible for everyday objects.<span class="nowrap"> </span> For example, a one-milliwatt <a href="/wiki/Laser_pointer" title="Laser pointer">laser pointer</a> exerts a force of about 3.3 <a href="/wiki/Newton_(unit)" title="Newton (unit)">piconewtons</a> on the object being illuminated; thus, one could lift a <a href="/wiki/Penny_(United_States_coin)" title="Penny (United States coin)">U.S. penny</a> with laser pointers, but doing so would require about 30 billion 1-mW laser pointers.<sup id="cite_ref-22" class="reference"><a href="#cite_note-22"><span class="cite-bracket">[</span>22<span class="cite-bracket">]</span></a></sup><span class="nowrap"> </span> However, in <a href="/wiki/Nanometre" title="Nanometre">nanometre</a>-scale applications such as <a href="/wiki/Nanoelectromechanical_systems" title="Nanoelectromechanical systems">nanoelectromechanical systems</a> (NEMS), the effect of light pressure is more significant and exploiting light pressure to drive NEMS mechanisms and to flip nanometre-scale physical switches in integrated circuits is an active area of research.<sup id="cite_ref-23" class="reference"><a href="#cite_note-23"><span class="cite-bracket">[</span>23<span class="cite-bracket">]</span></a></sup> At larger scales, light pressure can cause <a href="/wiki/Asteroid" title="Asteroid">asteroids</a> to spin faster,<sup id="cite_ref-24" class="reference"><a href="#cite_note-24"><span class="cite-bracket">[</span>24<span class="cite-bracket">]</span></a></sup> acting on their irregular shapes as on the vanes of a <a href="/wiki/Windmill" title="Windmill">windmill</a>.<span class="nowrap"> </span> The possibility of making <a href="/wiki/Solar_sail" title="Solar sail">solar sails</a> that would accelerate spaceships in space is also under investigation.<sup id="cite_ref-25" class="reference"><a href="#cite_note-25"><span class="cite-bracket">[</span>25<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-26" class="reference"><a href="#cite_note-26"><span class="cite-bracket">[</span>26<span class="cite-bracket">]</span></a></sup> </p><p>Although the motion of the <a href="/wiki/Crookes_radiometer" title="Crookes radiometer">Crookes radiometer</a> was originally attributed to light pressure, this interpretation is incorrect; the characteristic Crookes rotation is the result of a partial vacuum.<sup id="cite_ref-27" class="reference"><a href="#cite_note-27"><span class="cite-bracket">[</span>27<span class="cite-bracket">]</span></a></sup> This should not be confused with the <a href="/wiki/Nichols_radiometer" title="Nichols radiometer">Nichols radiometer</a>, in which the (slight) motion caused by torque (though not enough for full rotation against friction) <i>is</i> directly caused by light pressure.<sup id="cite_ref-28" class="reference"><a href="#cite_note-28"><span class="cite-bracket">[</span>28<span class="cite-bracket">]</span></a></sup> As a consequence of light pressure, <a href="/wiki/Albert_Einstein" title="Albert Einstein">Einstein</a> in 1909 predicted the existence of "radiation friction" which would oppose the movement of matter.<sup id="cite_ref-29" class="reference"><a href="#cite_note-29"><span class="cite-bracket">[</span>29<span class="cite-bracket">]</span></a></sup> He wrote, "radiation will exert pressure on both sides of the plate. The forces of pressure exerted on the two sides are equal if the plate is at rest. However, if it is in motion, more radiation will be reflected on the surface that is ahead during the motion (front surface) than on the back surface. The backwardacting force of pressure exerted on the front surface is thus larger than the force of pressure acting on the back. Hence, as the resultant of the two forces, there remains a force that counteracts the motion of the plate and that increases with the velocity of the plate. We will call this resultant 'radiation friction' in brief." </p><p>Usually light momentum is aligned with its direction of motion. However, for example in <a href="/wiki/Evanescent_wave" class="mw-redirect" title="Evanescent wave">evanescent waves</a> momentum is transverse to direction of propagation.<sup id="cite_ref-30" class="reference"><a href="#cite_note-30"><span class="cite-bracket">[</span>30<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Historical_theories_about_light,_in_chronological_order"><span id="Historical_theories_about_light.2C_in_chronological_order"></span>Historical theories about light, in chronological order</h2></div> <div class="mw-heading mw-heading3"><h3 id="Classical_Greece_and_Hellenism">Classical Greece and Hellenism</h3></div> <p>In the fifth century BC, <a href="/wiki/Empedocles" title="Empedocles">Empedocles</a> postulated that everything was composed of <a href="/wiki/Classical_element" title="Classical element">four elements</a>; fire, air, earth and water. He believed that goddess <a href="/wiki/Aphrodite" title="Aphrodite">Aphrodite</a> made the human eye out of the four elements and that she lit the fire in the eye which shone out from the eye making sight possible. If this were true, then one could see during the night just as well as during the day, so Empedocles postulated an interaction between rays from the eyes and rays from a source such as the sun.<sup id="cite_ref-31" class="reference"><a href="#cite_note-31"><span class="cite-bracket">[</span>31<span class="cite-bracket">]</span></a></sup> </p><p>In about 300 BC, <a href="/wiki/Euclid" title="Euclid">Euclid</a> wrote <i>Optica</i>, in which he studied the properties of light. Euclid postulated that light travelled in straight lines and he described the laws of reflection and studied them mathematically. He questioned that sight is the result of a beam from the eye, for he asks how one sees the stars immediately, if one closes one's eyes, then opens them at night. If the beam from the eye travels infinitely fast this is not a problem.<sup id="cite_ref-32" class="reference"><a href="#cite_note-32"><span class="cite-bracket">[</span>32<span class="cite-bracket">]</span></a></sup> </p><p>In 55 BC, <a href="/wiki/Lucretius" title="Lucretius">Lucretius</a>, a Roman who carried on the ideas of earlier Greek <a href="/wiki/Atomism" title="Atomism">atomists</a>, wrote that "The light & heat of the sun; these are composed of minute atoms which, when they are shoved off, lose no time in shooting right across the interspace of air in the direction imparted by the shove." (from <i>On the nature of the Universe</i>). Despite being similar to later particle theories, Lucretius's views were not generally accepted. <a href="/wiki/Ptolemy" title="Ptolemy">Ptolemy</a> (c. second century) wrote about the <a href="/wiki/Refraction" title="Refraction">refraction</a> of light in his book <i>Optics</i>.<sup id="cite_ref-33" class="reference"><a href="#cite_note-33"><span class="cite-bracket">[</span>33<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Classical_India">Classical India</h3></div> <p>In <a href="/wiki/Science_and_technology_in_ancient_India" class="mw-redirect" title="Science and technology in ancient India">ancient India</a>, the <a href="/wiki/Hindu" class="mw-redirect" title="Hindu">Hindu</a> schools of <a href="/wiki/Samkhya" title="Samkhya">Samkhya</a> and <a href="/wiki/Vaisheshika" title="Vaisheshika">Vaisheshika</a>, from around the early centuries AD developed theories on light. According to the Samkhya school, light is one of the five fundamental "subtle" elements (<i>tanmatra</i>) out of which emerge the gross elements. The <a href="/wiki/Atomism" title="Atomism">atomicity</a> of these elements is not specifically mentioned and it appears that they were actually taken to be continuous.<sup id="cite_ref-sifuae.com_34-0" class="reference"><a href="#cite_note-sifuae.com-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> The <i><a href="/wiki/Vishnu_Purana" title="Vishnu Purana">Vishnu Purana</a></i> refers to sunlight as "the seven rays of the sun".<sup id="cite_ref-sifuae.com_34-1" class="reference"><a href="#cite_note-sifuae.com-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p><p>The Indian <a href="/wiki/Buddhist" class="mw-redirect" title="Buddhist">Buddhists</a>, such as <a href="/wiki/Dign%C4%81ga" title="Dignāga">Dignāga</a> in the fifth century and <a href="/wiki/Dharmakirti" title="Dharmakirti">Dharmakirti</a> in the seventh century, developed a type of atomism that is a philosophy about reality being composed of atomic entities that are momentary flashes of light or energy. They viewed light as being an atomic entity equivalent to energy.<sup id="cite_ref-sifuae.com_34-2" class="reference"><a href="#cite_note-sifuae.com-34"><span class="cite-bracket">[</span>34<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Descartes">Descartes</h3></div> <p><a href="/wiki/Ren%C3%A9_Descartes" title="René Descartes">René Descartes</a> (1596–1650) held that light was a <a href="/wiki/Mechanism_(philosophy)" title="Mechanism (philosophy)">mechanical</a> property of the luminous body, rejecting the "forms" of <a href="/wiki/Alhazen" class="mw-redirect" title="Alhazen">Ibn al-Haytham</a> and <a href="/wiki/Witelo" class="mw-redirect" title="Witelo">Witelo</a> as well as the "species" of <a href="/wiki/Roger_Bacon#Legacy" title="Roger Bacon">Roger Bacon</a>, <a href="/wiki/Robert_Grosseteste" title="Robert Grosseteste">Robert Grosseteste</a> and <a href="/wiki/Johannes_Kepler" title="Johannes Kepler">Johannes Kepler</a>.<sup id="cite_ref-Theories_of_light_35-0" class="reference"><a href="#cite_note-Theories_of_light-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> In 1637 he published a theory of the <a href="/wiki/Refraction" title="Refraction">refraction</a> of light that assumed, incorrectly, that light travelled faster in a denser medium than in a less dense medium. Descartes arrived at this conclusion by analogy with the behaviour of sound waves.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (January 2010)">citation needed</span></a></i>]</sup> Although Descartes was incorrect about the relative speeds, he was correct in assuming that light behaved like a wave and in concluding that refraction could be explained by the speed of light in different media. </p><p>Descartes is not the first to use the mechanical analogies but because he clearly asserts that light is only a mechanical property of the luminous body and the transmitting medium, Descartes's theory of light is regarded as the start of modern physical optics.<sup id="cite_ref-Theories_of_light_35-1" class="reference"><a href="#cite_note-Theories_of_light-35"><span class="cite-bracket">[</span>35<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Particle_theory">Particle theory</h3></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Corpuscular_theory_of_light" title="Corpuscular theory of light">Corpuscular theory of light</a></div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:PierreGassendi.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c8/PierreGassendi.jpg/200px-PierreGassendi.jpg" decoding="async" width="200" height="239" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c8/PierreGassendi.jpg/300px-PierreGassendi.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c8/PierreGassendi.jpg/400px-PierreGassendi.jpg 2x" data-file-width="758" data-file-height="906" /></a><figcaption><a href="/wiki/Pierre_Gassendi" title="Pierre Gassendi">Pierre Gassendi</a></figcaption></figure> <p><a href="/wiki/Pierre_Gassendi" title="Pierre Gassendi">Pierre Gassendi</a> (1592–1655), an atomist, proposed a particle theory of light which was published posthumously in the 1660s. <a href="/wiki/Isaac_Newton" title="Isaac Newton">Isaac Newton</a> studied Gassendi's work at an early age and preferred his view to Descartes's theory of the <i>plenum</i>. He stated in his <i>Hypothesis of Light</i> of 1675 that light was composed of <a href="/wiki/Corpuscularianism" title="Corpuscularianism">corpuscles</a> (particles of matter) which were emitted in all directions from a source. One of Newton's arguments against the wave nature of light was that waves were known to bend around obstacles, while light travelled only in straight lines. He did, however, explain the phenomenon of the <a href="/wiki/Diffraction" title="Diffraction">diffraction</a> of light (which had been observed by <a href="/wiki/Francesco_Maria_Grimaldi" title="Francesco Maria Grimaldi">Francesco Grimaldi</a>) by allowing that a light particle could create a localised wave in the <a href="/wiki/Aether_(classical_element)" title="Aether (classical element)">aether</a>. </p><p>Newton's theory could be used to predict the <a href="/wiki/Reflection_(physics)" title="Reflection (physics)">reflection</a> of light, but could only explain <a href="/wiki/Refraction" title="Refraction">refraction</a> by incorrectly assuming that light accelerated upon entering a denser <a href="/wiki/Medium_(optics)" class="mw-redirect" title="Medium (optics)">medium</a> because the <a href="/wiki/Gravity" title="Gravity">gravitational</a> pull was greater. Newton published the final version of his theory in his <i><a href="/wiki/Opticks" title="Opticks">Opticks</a></i> of 1704. His reputation helped the <a href="/wiki/Particle_theory_of_light" class="mw-redirect" title="Particle theory of light">particle theory of light</a> to hold sway during the eighteenth century. The particle theory of light led <a href="/wiki/Pierre-Simon_Laplace" title="Pierre-Simon Laplace">Pierre-Simon Laplace</a> to argue that a body could be so massive that light could not escape from it. In other words, it would become what is now called a <a href="/wiki/Black_hole" title="Black hole">black hole</a>. Laplace withdrew his suggestion later, after a wave theory of light became firmly established as the model for light (as has been explained, neither a particle or wave theory is fully correct). A translation of Newton's essay on light appears in <i>The large scale structure of space-time</i>, by <a href="/wiki/Stephen_Hawking" title="Stephen Hawking">Stephen Hawking</a> and <a href="/wiki/George_F._R._Ellis" title="George F. R. Ellis">George F. R. Ellis</a>. </p><p>The fact that light could be <a href="/wiki/Polarized_light" class="mw-redirect" title="Polarized light">polarized</a> was for the first time qualitatively explained by Newton using the particle theory. <a href="/wiki/%C3%89tienne-Louis_Malus" title="Étienne-Louis Malus">Étienne-Louis Malus</a> in 1810 created a mathematical particle theory of polarization. <a href="/wiki/Jean-Baptiste_Biot" title="Jean-Baptiste Biot">Jean-Baptiste Biot</a> in 1812 showed that this theory explained all known phenomena of light polarization. At that time the polarization was considered as the proof of the particle theory. </p> <div class="mw-heading mw-heading3"><h3 id="Wave_theory">Wave theory</h3></div> <p>To explain the origin of <a href="/wiki/Colour" class="mw-redirect" title="Colour">colours</a>, <a href="/wiki/Robert_Hooke" title="Robert Hooke">Robert Hooke</a> (1635–1703) developed a "pulse theory" and compared the spreading of light to that of waves in water in his 1665 work <i><a href="/wiki/Micrographia" title="Micrographia">Micrographia</a></i> ("Observation IX"). In 1672 Hooke suggested that light's vibrations could be <a href="/wiki/Perpendicular" title="Perpendicular">perpendicular</a> to the direction of propagation. <a href="/wiki/Christiaan_Huygens" title="Christiaan Huygens">Christiaan Huygens</a> (1629–1695) worked out a mathematical wave theory of light in 1678 and published it in his <i><a href="/wiki/Treatise_on_Light" title="Treatise on Light">Treatise on Light</a></i> in 1690. He proposed that light was emitted in all directions as a series of waves in a medium called the <a href="/wiki/Luminiferous_aether" title="Luminiferous aether">luminiferous aether</a>. As waves are not affected by gravity, it was assumed that they slowed down upon entering a denser medium.<sup id="cite_ref-36" class="reference"><a href="#cite_note-36"><span class="cite-bracket">[</span>36<span class="cite-bracket">]</span></a></sup> </p> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Christiaan_Huygens-painting.jpeg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Christiaan_Huygens-painting.jpeg/200px-Christiaan_Huygens-painting.jpeg" decoding="async" width="200" height="262" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Christiaan_Huygens-painting.jpeg/300px-Christiaan_Huygens-painting.jpeg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a4/Christiaan_Huygens-painting.jpeg/400px-Christiaan_Huygens-painting.jpeg 2x" data-file-width="1682" data-file-height="2204" /></a><figcaption><a href="/wiki/Christiaan_Huygens" title="Christiaan Huygens">Christiaan Huygens</a></figcaption></figure> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Young_Diffraction.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Young_Diffraction.png/200px-Young_Diffraction.png" decoding="async" width="200" height="89" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Young_Diffraction.png/300px-Young_Diffraction.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8a/Young_Diffraction.png/400px-Young_Diffraction.png 2x" data-file-width="1988" data-file-height="882" /></a><figcaption><a href="/wiki/Thomas_Young_(scientist)" title="Thomas Young (scientist)">Thomas Young</a>'s sketch of a <a href="/wiki/Double-slit_experiment" title="Double-slit experiment">double-slit experiment</a> showing <a href="/wiki/Diffraction" title="Diffraction">diffraction</a>. Young's experiments supported the theory that light consists of waves.</figcaption></figure> <p>The wave theory predicted that light waves could interfere with each other like sound waves (as noted around 1800 by <a href="/wiki/Thomas_Young_(scientist)" title="Thomas Young (scientist)">Thomas Young</a>). Young showed by means of a <a href="/wiki/Double-slit_experiment" title="Double-slit experiment">diffraction experiment</a> that light behaved as waves. He also proposed that different colours were caused by different <a href="/wiki/Wavelength" title="Wavelength">wavelengths</a> of light and explained colour vision in terms of three-coloured receptors in the eye. Another supporter of the wave theory was <a href="/wiki/Leonhard_Euler" title="Leonhard Euler">Leonhard Euler</a>. He argued in <i>Nova theoria lucis et colorum</i> (1746) that <a href="/wiki/Diffraction" title="Diffraction">diffraction</a> could more easily be explained by a wave theory. In 1816 <a href="/wiki/Andr%C3%A9-Marie_Amp%C3%A8re" title="André-Marie Ampère">André-Marie Ampère</a> gave <a href="/wiki/Augustin-Jean_Fresnel" title="Augustin-Jean Fresnel">Augustin-Jean Fresnel</a> an idea that the polarization of light can be explained by the wave theory if light were a <a href="/wiki/Transverse_wave" title="Transverse wave">transverse wave</a>.<sup id="cite_ref-37" class="reference"><a href="#cite_note-37"><span class="cite-bracket">[</span>37<span class="cite-bracket">]</span></a></sup> </p><p>Later, Fresnel independently worked out his own wave theory of light and presented it to the <a href="/wiki/Acad%C3%A9mie_des_Sciences" class="mw-redirect" title="Académie des Sciences">Académie des Sciences</a> in 1817. <a href="/wiki/Sim%C3%A9on_Denis_Poisson" title="Siméon Denis Poisson">Siméon Denis Poisson</a> added to Fresnel's mathematical work to produce a convincing argument in favor of the wave theory, helping to overturn Newton's corpuscular theory.<sup class="noprint Inline-Template" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Accuracy_dispute#Disputed_statement" title="Wikipedia:Accuracy dispute"><span title="The material near this tag is possibly inaccurate or nonfactual. (June 2018)">dubious</span></a> – <a href="/wiki/Talk:Light#Dubious" title="Talk:Light">discuss</a></i>]</sup> By the year 1821, Fresnel was able to show via mathematical methods that polarization could be explained by the wave theory of light if and only if light was entirely transverse, with no longitudinal vibration whatsoever.<sup class="noprint Inline-Template Template-Fact" style="white-space:nowrap;">[<i><a href="/wiki/Wikipedia:Citation_needed" title="Wikipedia:Citation needed"><span title="This claim needs references to reliable sources. (June 2018)">citation needed</span></a></i>]</sup> </p><p>The weakness of the wave theory was that light waves, like sound waves, would need a medium for transmission. The existence of the hypothetical substance luminiferous aether proposed by Huygens in 1678 was cast into strong doubt in the late nineteenth century by the <a href="/wiki/Michelson%E2%80%93Morley_experiment" title="Michelson–Morley experiment">Michelson–Morley experiment</a>. </p><p>Newton's corpuscular theory implied that light would travel faster in a denser medium, while the wave theory of Huygens and others implied the opposite. At that time, the <a href="/wiki/Speed_of_light" title="Speed of light">speed of light</a> could not be measured accurately enough to decide which theory was correct. The first to make a sufficiently accurate measurement was <a href="/wiki/L%C3%A9on_Foucault" title="Léon Foucault">Léon Foucault</a>, in 1850.<sup id="cite_ref-38" class="reference"><a href="#cite_note-38"><span class="cite-bracket">[</span>38<span class="cite-bracket">]</span></a></sup> His result supported the wave theory, and the classical particle theory was finally abandoned (only to partly re-emerge in the twentieth century as <a href="/wiki/Photons" class="mw-redirect" title="Photons">photons</a> in <a href="/wiki/Quantum_mechanics" title="Quantum mechanics">quantum theory</a>). </p> <div class="mw-heading mw-heading3"><h3 id="Electromagnetic_theory">Electromagnetic theory</h3></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Electromagnetic_radiation" title="Electromagnetic radiation">Electromagnetic radiation</a></div> <figure typeof="mw:File/Thumb"><a href="/wiki/File:Onde_electromagnetique.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/35/Onde_electromagnetique.svg/400px-Onde_electromagnetique.svg.png" decoding="async" width="400" height="99" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/35/Onde_electromagnetique.svg/600px-Onde_electromagnetique.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/35/Onde_electromagnetique.svg/800px-Onde_electromagnetique.svg.png 2x" data-file-width="714" data-file-height="176" /></a><figcaption>A <a href="/wiki/Linear_polarization" title="Linear polarization">linearly polarized</a> electromagnetic wave traveling along the z-axis, with E denoting the <a href="/wiki/Electric_field" title="Electric field">electric field</a> and perpendicular B denoting <a href="/wiki/Magnetic_field" title="Magnetic field">magnetic field</a></figcaption></figure> <p>In 1845, <a href="/wiki/Michael_Faraday" title="Michael Faraday">Michael Faraday</a> discovered that the plane of polarization of linearly polarized light is rotated when the light rays travel along the <a href="/wiki/Magnetic_field" title="Magnetic field">magnetic field</a> direction in the presence of a transparent <a href="/wiki/Dielectric" title="Dielectric">dielectric</a>, an effect now known as <a href="/wiki/Faraday_rotation" class="mw-redirect" title="Faraday rotation">Faraday rotation</a>.<sup id="cite_ref-LongairMalcolm_39-0" class="reference"><a href="#cite_note-LongairMalcolm-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> This was the first evidence that light was related to <a href="/wiki/Electromagnetism" title="Electromagnetism">electromagnetism</a>. In 1846 he speculated that light might be some form of disturbance propagating along magnetic field lines.<sup id="cite_ref-LongairMalcolm_39-1" class="reference"><a href="#cite_note-LongairMalcolm-39"><span class="cite-bracket">[</span>39<span class="cite-bracket">]</span></a></sup> Faraday proposed in 1847 that light was a high-frequency electromagnetic vibration, which could propagate even in the absence of a medium such as the ether.<sup id="cite_ref-40" class="reference"><a href="#cite_note-40"><span class="cite-bracket">[</span>40<span class="cite-bracket">]</span></a></sup> </p><p>Faraday's work inspired <a href="/wiki/James_Clerk_Maxwell" title="James Clerk Maxwell">James Clerk Maxwell</a> to study electromagnetic radiation and light. Maxwell discovered that self-propagating electromagnetic waves would travel through space at a constant speed, which happened to be equal to the previously measured speed of light. From this, Maxwell concluded that light was a form of electromagnetic radiation: he first stated this result in 1862 in <i>On Physical Lines of Force</i>. In 1873, he published <i><a href="/wiki/A_Treatise_on_Electricity_and_Magnetism" title="A Treatise on Electricity and Magnetism">A Treatise on Electricity and Magnetism</a></i>, which contained a full mathematical description of the behavior of electric and magnetic fields, still known as <a href="/wiki/Maxwell%27s_equations" title="Maxwell's equations">Maxwell's equations</a>. Soon after, <a href="/wiki/Heinrich_Hertz" title="Heinrich Hertz">Heinrich Hertz</a> confirmed Maxwell's theory experimentally by generating and detecting radio waves in the laboratory and demonstrating that these waves behaved exactly like visible light, exhibiting properties such as reflection, refraction, diffraction and <a href="/wiki/Wave_interference" title="Wave interference">interference</a>. Maxwell's theory and Hertz's experiments led directly to the development of modern radio, radar, television, electromagnetic imaging and wireless communications. </p><p>In the quantum theory, photons are seen as <a href="/wiki/Wave_packet" title="Wave packet">wave packets</a> of the waves described in the classical theory of Maxwell. The quantum theory was needed to explain effects even with visual light that Maxwell's classical theory could not (such as <a href="/wiki/Spectral_line" title="Spectral line">spectral lines</a>). </p> <div class="mw-heading mw-heading3"><h3 id="Quantum_theory">Quantum theory</h3></div> <p>In 1900 <a href="/wiki/Max_Planck" title="Max Planck">Max Planck</a>, attempting to explain <a href="/wiki/Black-body_radiation" title="Black-body radiation">black-body radiation</a>, suggested that although light was a wave, these waves could gain or lose energy only in finite amounts related to their frequency. Planck called these "lumps" of light energy "<a href="/wiki/Quantum" title="Quantum">quanta</a>" (from a Latin word for "how much"). In 1905, Albert Einstein used the idea of light quanta to explain the <a href="/wiki/Photoelectric_effect" title="Photoelectric effect">photoelectric effect</a> and suggested that these light quanta had a "real" existence. In 1923 <a href="/wiki/Arthur_Holly_Compton" class="mw-redirect" title="Arthur Holly Compton">Arthur Holly Compton</a> showed that the wavelength shift seen when low intensity X-rays scattered from electrons (so called <a href="/wiki/Compton_scattering" title="Compton scattering">Compton scattering</a>) could be explained by a particle-theory of X-rays, but not a wave theory. In 1926 <a href="/wiki/Gilbert_N._Lewis" title="Gilbert N. Lewis">Gilbert N. Lewis</a> named these light quanta particles <a href="/wiki/Photon" title="Photon">photons</a>.<sup id="cite_ref-41" class="reference"><a href="#cite_note-41"><span class="cite-bracket">[</span>41<span class="cite-bracket">]</span></a></sup> </p><p>Eventually <a href="/wiki/Quantum_mechanics" title="Quantum mechanics">quantum mechanics</a> came to picture light as (in some sense) <i>both</i> a particle and a wave, and (in another sense) as a phenomenon which is <i>neither</i> a particle nor a wave (which actually are macroscopic phenomena, such as baseballs or ocean waves). Instead, under some approximations light can be described sometimes with mathematics appropriate to one type of macroscopic metaphor (particles) and sometimes another macroscopic metaphor (waves). </p><p>As in the case for radio waves and the X-rays involved in Compton scattering, physicists have noted that electromagnetic radiation tends to behave more like a classical wave at lower frequencies, but more like a classical particle at higher frequencies, but never completely loses all qualities of one or the other. Visible light, which occupies a middle ground in frequency, can easily be shown in experiments to be describable using either a wave or particle model, or sometimes both. </p><p>In 1924–1925, <a href="/wiki/Satyendra_Nath_Bose" title="Satyendra Nath Bose">Satyendra Nath Bose</a> showed that light followed different statistics from that of classical particles. With Einstein, they generalized this result for a whole set of integer spin particles called <a href="/wiki/Boson" title="Boson">bosons</a> (after Bose) that follow <a href="/wiki/Bose%E2%80%93Einstein_statistics" title="Bose–Einstein statistics">Bose–Einstein statistics</a>. The photon is a massless boson of spin 1. </p><p>In 1927, <a href="/wiki/Paul_Dirac" title="Paul Dirac">Paul Dirac</a> quantized the <a href="/wiki/Electromagnetic_field" title="Electromagnetic field">electromagnetic field</a>. <a href="/wiki/Pascual_Jordan" title="Pascual Jordan">Pascual Jordan</a> and <a href="/wiki/Vladimir_Fock" title="Vladimir Fock">Vladimir Fock</a> generalized this process to treat many-body systems as excitations of quantum fields, a process with the misnomer of <a href="/wiki/Second_quantization" title="Second quantization">second quantization</a>. And at the end of the 1940s a full theory of <a href="/wiki/Quantum_electrodynamics" title="Quantum electrodynamics">quantum electrodynamics</a> was developed using quantum fields based on the works of <a href="/wiki/Julian_Schwinger" title="Julian Schwinger">Julian Schwinger</a>, <a href="/wiki/Richard_Feynman" title="Richard Feynman">Richard Feynman</a>, <a href="/wiki/Freeman_Dyson" title="Freeman Dyson">Freeman Dyson</a>, and <a href="/wiki/Shinichiro_Tomonaga" class="mw-redirect" title="Shinichiro Tomonaga">Shinichiro Tomonaga</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Quantum_optics">Quantum optics</h3></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/Quantum_optics" title="Quantum optics">Quantum optics</a></div> <p><a href="/wiki/John_R._Klauder" title="John R. Klauder">John R. Klauder</a>, <a href="/wiki/George_Sudarshan" class="mw-redirect" title="George Sudarshan">George Sudarshan</a>, <a href="/wiki/Roy_J._Glauber" title="Roy J. Glauber">Roy J. Glauber</a>, and <a href="/wiki/Leonard_Mandel" title="Leonard Mandel">Leonard Mandel</a> applied quantum theory to the electromagnetic field in the 1950s and 1960s to gain a more detailed understanding of photodetection and the <a href="/wiki/Statistical_mechanics" title="Statistical mechanics">statistics</a> of light (see <a href="/wiki/Degree_of_coherence" class="mw-redirect" title="Degree of coherence">degree of coherence</a>). This led to the introduction of the <a href="/wiki/Coherent_state" title="Coherent state">coherent state</a> as a concept which addressed variations between laser light, thermal light, exotic <a href="/wiki/Squeezed_state" class="mw-redirect" title="Squeezed state">squeezed states</a>, etc. as it became understood that light cannot be fully described just referring to the <a href="/wiki/Electromagnetic_field" title="Electromagnetic field">electromagnetic fields</a> describing the waves in the classical picture. In 1977, <a href="/wiki/H._Jeff_Kimble" title="H. Jeff Kimble">H. Jeff Kimble</a> et al. demonstrated a single atom emitting one photon at a time, further compelling evidence that light consists of photons. Previously unknown quantum states of light with characteristics unlike classical states, such as <a href="/wiki/Squeezed_coherent_state" title="Squeezed coherent state">squeezed light</a> were subsequently discovered. </p><p>Development of short and <a href="/wiki/Ultrashort_pulse" title="Ultrashort pulse">ultrashort</a> laser pulses—created by <a href="/wiki/Q_switching" class="mw-redirect" title="Q switching">Q switching</a> and <a href="/wiki/Modelocking" class="mw-redirect" title="Modelocking">modelocking</a> techniques—opened the way to the study of what became known as ultrafast processes. Applications for solid state research (e.g. <a href="/wiki/Raman_spectroscopy" title="Raman spectroscopy">Raman spectroscopy</a>) were found, and mechanical forces of light on matter were studied. The latter led to levitating and positioning clouds of atoms or even small biological samples in an <a href="/wiki/Optical_trap" class="mw-redirect" title="Optical trap">optical trap</a> or <a href="/wiki/Optical_tweezers" title="Optical tweezers">optical tweezers</a> by laser beam. This, along with <a href="/wiki/Doppler_cooling" title="Doppler cooling">Doppler cooling</a> and <a href="/wiki/Sisyphus_cooling" title="Sisyphus cooling">Sisyphus cooling</a>, was the crucial technology needed to achieve the celebrated <a href="/wiki/Bose%E2%80%93Einstein_condensation" class="mw-redirect" title="Bose–Einstein condensation">Bose–Einstein condensation</a>. </p><p>Other remarkable results are the <a href="/wiki/Bell_test_experiments" class="mw-redirect" title="Bell test experiments">demonstration of quantum entanglement</a>, <a href="/wiki/Quantum_teleportation" title="Quantum teleportation">quantum teleportation</a>, and <a href="/wiki/Quantum_logic_gate" title="Quantum logic gate">quantum logic gates</a>. The latter are of much interest in <a href="/wiki/Quantum_information_theory" class="mw-redirect" title="Quantum information theory">quantum information theory</a>, a subject which partly emerged from quantum optics, partly from theoretical <a href="/wiki/Computer_science" title="Computer science">computer science</a>. </p> <div class="mw-heading mw-heading2"><h2 id="Use_for_light_on_Earth">Use for light on Earth</h2></div> <p><a href="/wiki/Sunlight" title="Sunlight">Sunlight</a> provides the <a href="/wiki/Energy" title="Energy">energy</a> that <a href="/wiki/Green_plants" class="mw-redirect" title="Green plants">green plants</a> use to create <a href="/wiki/Sugars" class="mw-redirect" title="Sugars">sugars</a> mostly in the form of <a href="/wiki/Starch" title="Starch">starches</a>, which release energy into the living things that digest them. This process of <a href="/wiki/Photosynthesis" title="Photosynthesis">photosynthesis</a> provides virtually all the energy used by living things. Some species of animals generate their own light, a process called <a href="/wiki/Bioluminescence" title="Bioluminescence">bioluminescence</a>. For example, <a href="/wiki/Fireflies" class="mw-redirect" title="Fireflies">fireflies</a> use light to locate mates and <a href="/wiki/Vampire_squid" title="Vampire squid">vampire squid</a> use it to hide themselves from prey. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2></div> <style data-mw-deduplicate="TemplateStyles:r1239009302">.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output .portalbox-entry{display:table-row;font-size:85%;line-height:110%;height:1.9em;font-style:italic;font-weight:bold}.mw-parser-output .portalbox-image{display:table-cell;padding:0.2em;vertical-align:middle;text-align:center}.mw-parser-output .portalbox-link{display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle}@media(min-width:720px){.mw-parser-output .portalleft{clear:left;float:left;margin:0.5em 1em 0.5em 0}.mw-parser-output .portalright{clear:right;float:right;margin:0.5em 0 0.5em 1em}}</style><ul role="navigation" aria-label="Portals" class="noprint portalbox portalborder portalright"> <li class="portalbox-entry"><span class="portalbox-image"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/25px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png" decoding="async" width="25" height="28" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/37px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/49px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 2x" data-file-width="530" data-file-height="600" /></a></span></span><span class="portalbox-link"><a href="/wiki/Portal:Physics" title="Portal:Physics">Physics portal</a></span></li><li class="portalbox-entry"><span class="portalbox-image"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Nuvola_apps_kalzium.svg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Nuvola_apps_kalzium.svg/28px-Nuvola_apps_kalzium.svg.png" decoding="async" width="28" height="28" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Nuvola_apps_kalzium.svg/42px-Nuvola_apps_kalzium.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8b/Nuvola_apps_kalzium.svg/56px-Nuvola_apps_kalzium.svg.png 2x" data-file-width="128" data-file-height="128" /></a></span></span><span class="portalbox-link"><a href="/wiki/Portal:Science" title="Portal:Science">Science portal</a></span></li></ul> <style data-mw-deduplicate="TemplateStyles:r1184024115">.mw-parser-output .div-col{margin-top:0.3em;column-width:30em}.mw-parser-output .div-col-small{font-size:90%}.mw-parser-output .div-col-rules{column-rule:1px solid #aaa}.mw-parser-output .div-col dl,.mw-parser-output .div-col ol,.mw-parser-output .div-col ul{margin-top:0}.mw-parser-output .div-col li,.mw-parser-output .div-col dd{page-break-inside:avoid;break-inside:avoid-column}</style><div class="div-col" style="column-width: 26em;"> <ul><li><a href="/wiki/Ballistic_photon" title="Ballistic photon">Ballistic photon</a></li> <li><a href="/wiki/Colour_temperature" class="mw-redirect" title="Colour temperature">Colour temperature</a></li> <li><a href="/wiki/Fermat%27s_principle" title="Fermat's principle">Fermat's principle</a></li> <li><a href="/wiki/Huygens%27_principle" class="mw-redirect" title="Huygens' principle">Huygens' principle</a></li> <li><i><a href="/wiki/Journal_of_Luminescence" title="Journal of Luminescence">Journal of Luminescence</a></i></li> <li><a href="/wiki/Light_beam" title="Light beam">Light beam</a> – in particular about light beams visible from the side</li> <li><a href="/wiki/Light_Fantastic_(TV_series)" title="Light Fantastic (TV series)"><i>Light Fantastic</i> (TV series)</a></li> <li><a href="/wiki/Light_mill" class="mw-redirect" title="Light mill">Light mill</a></li> <li><a href="/wiki/List_of_light_sources" title="List of light sources">List of light sources</a></li> <li><i><a href="/wiki/Luminescence:_The_Journal_of_Biological_and_Chemical_Luminescence" class="mw-redirect" title="Luminescence: The Journal of Biological and Chemical Luminescence">Luminescence: The Journal of Biological and Chemical Luminescence</a></i></li> <li><a href="/wiki/Spectroscopy" title="Spectroscopy">Spectroscopy</a></li></ul> </div> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> </div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><a href="/wiki/International_Commission_on_Illumination" title="International Commission on Illumination">CIE</a> (1987). <a rel="nofollow" class="external text" href="http://www.cie.co.at/publ/abst/17-4-89.html"><i>International Lighting Vocabulary</i></a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20100227034508/http://www.cie.co.at/publ/abst/17-4-89.html">Archived</a> 27 February 2010 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a>. Number 17.4. CIE, 4th ed.. <style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-3-900734-07-7" title="Special:BookSources/978-3-900734-07-7">978-3-900734-07-7</a>.<br />By the <i>International Lighting Vocabulary</i>, the definition of <i>light</i> is: "Any radiation capable of causing a visual sensation directly."</span> </li> <li id="cite_note-Pal2001-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-Pal2001_2-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPalPal2001" class="citation book cs1">Pal, G.K.; Pal, Pravati (2001). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=CcJvIiesqp8C&pg=PA387">"chapter 52"</a>. <i>Textbook of Practical Physiology</i> (1st ed.). Chennai: Orient Blackswan. p. 387. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-81-250-2021-9" title="Special:BookSources/978-81-250-2021-9"><bdi>978-81-250-2021-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221008031819/https://books.google.com/books?id=CcJvIiesqp8C&pg=PA387">Archived</a> from the original on 8 October 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">11 October</span> 2013</span>. <q>The human eye has the ability to respond to all the wavelengths of light from 400–700 nm. This is called the visible part of the spectrum.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=chapter+52&rft.btitle=Textbook+of+Practical+Physiology&rft.place=Chennai&rft.pages=387&rft.edition=1st&rft.pub=Orient+Blackswan&rft.date=2001&rft.isbn=978-81-250-2021-9&rft.aulast=Pal&rft.aufirst=G.K.&rft.au=Pal%2C+Pravati&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DCcJvIiesqp8C%26pg%3DPA387&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-BuserImbert1992-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-BuserImbert1992_3-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBuserImbert1992" class="citation book cs1">Buser, Pierre A.; Imbert, Michel (1992). <span class="id-lock-registration" title="Free registration required"><a rel="nofollow" class="external text" href="https://archive.org/details/vision0000buse"><i>Vision</i></a></span>. MIT Press. p. <a rel="nofollow" class="external text" href="https://archive.org/details/vision0000buse/page/50">50</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-262-02336-8" title="Special:BookSources/978-0-262-02336-8"><bdi>978-0-262-02336-8</bdi></a><span class="reference-accessdate">. Retrieved <span class="nowrap">11 October</span> 2013</span>. <q>Light is a special class of radiant energy embracing wavelengths between 400 and 700 nm (or mμ), or 4000 to 7000 Å.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Vision&rft.pages=50&rft.pub=MIT+Press&rft.date=1992&rft.isbn=978-0-262-02336-8&rft.aulast=Buser&rft.aufirst=Pierre+A.&rft.au=Imbert%2C+Michel&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fvision0000buse&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFGregory_Hallock_Smith2006" class="citation book cs1">Gregory Hallock Smith (2006). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=6mb0C0cFCEYC&pg=PA4"><i>Camera lenses: from box camera to digital</i></a>. SPIE Press. p. 4. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-8194-6093-6" title="Special:BookSources/978-0-8194-6093-6"><bdi>978-0-8194-6093-6</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221008031820/https://books.google.com/books?id=6mb0C0cFCEYC&pg=PA4">Archived</a> from the original on 8 October 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">15 November</span> 2020</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Camera+lenses%3A+from+box+camera+to+digital&rft.pages=4&rft.pub=SPIE+Press&rft.date=2006&rft.isbn=978-0-8194-6093-6&rft.au=Gregory+Hallock+Smith&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D6mb0C0cFCEYC%26pg%3DPA4&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNarinder_Kumar2008" class="citation book cs1">Narinder Kumar (2008). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=IryMtwHHngIC&pg=PA1416"><i>Comprehensive Physics XII</i></a>. Laxmi Publications. p. 1416. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-81-7008-592-8" title="Special:BookSources/978-81-7008-592-8"><bdi>978-81-7008-592-8</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Comprehensive+Physics+XII&rft.pages=1416&rft.pub=Laxmi+Publications&rft.date=2008&rft.isbn=978-81-7008-592-8&rft.au=Narinder+Kumar&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DIryMtwHHngIC%26pg%3DPA1416&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-LeClerq-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-LeClerq_6-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFUzanLeclercq2008" class="citation book cs1">Uzan, J-P; Leclercq, B (2008). <a rel="nofollow" class="external text" href="https://archive.org/details/the-natural-laws-of-the-universe-understanding-fundamental-constants"><i>The Natural Laws of the Universe: Understanding Fundamental Constants</i></a>. Translated by Robert Mizon. <a href="/wiki/Springer-Praxis" class="mw-redirect" title="Springer-Praxis">Springer-Praxis</a>, <a href="/wiki/Internet_Archive" title="Internet Archive">Internet Archive</a>: 2020-06-14 AbdzexK uban. pp. 43–44. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2008nlu..book.....U">2008nlu..book.....U</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1007%2F978-0-387-74081-2">10.1007/978-0-387-74081-2</a> (inactive 1 November 2024). <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-387-73454-5" title="Special:BookSources/978-0-387-73454-5"><bdi>978-0-387-73454-5</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Natural+Laws+of+the+Universe%3A+Understanding+Fundamental+Constants&rft.pages=43-44&rft.pub=Springer-Praxis%2C+Internet+Archive%3A+2020-06-14+AbdzexK+uban&rft.date=2008&rft_id=info%3Adoi%2F10.1007%2F978-0-387-74081-2&rft_id=info%3Abibcode%2F2008nlu..book.....U&rft.isbn=978-0-387-73454-5&rft.aulast=Uzan&rft.aufirst=J-P&rft.au=Leclercq%2C+B&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fthe-natural-laws-of-the-universe-understanding-fundamental-constants&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span><span class="cs1-maint citation-comment"><code class="cs1-code">{{<a href="/wiki/Template:Cite_book" title="Template:Cite book">cite book</a>}}</code>: CS1 maint: DOI inactive as of November 2024 (<a href="/wiki/Category:CS1_maint:_DOI_inactive_as_of_November_2024" title="Category:CS1 maint: DOI inactive as of November 2024">link</a>)</span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLaufer1996" class="citation book cs1">Laufer, Gabriel (1996). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=4MxLPYMS5TUC&pg=PA11">"Geometrical Optics"</a>. <i>Introduction to Optics and Lasers in Engineering</i>. p. 11. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1996iole.book.....L">1996iole.book.....L</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1017%2FCBO9781139174190.004">10.1017/CBO9781139174190.004</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-521-45233-5" title="Special:BookSources/978-0-521-45233-5"><bdi>978-0-521-45233-5</bdi></a><span class="reference-accessdate">. Retrieved <span class="nowrap">20 October</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Geometrical+Optics&rft.btitle=Introduction+to+Optics+and+Lasers+in+Engineering&rft.pages=11&rft.date=1996&rft_id=info%3Adoi%2F10.1017%2FCBO9781139174190.004&rft_id=info%3Abibcode%2F1996iole.book.....L&rft.isbn=978-0-521-45233-5&rft.aulast=Laufer&rft.aufirst=Gabriel&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D4MxLPYMS5TUC%26pg%3DPA11&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-Bradt2004-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-Bradt2004_8-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBradt2004" class="citation book cs1">Bradt, Hale (2004). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=hp7vyaGvhLMC&pg=PA26"><i>Astronomy Methods: A Physical Approach to Astronomical Observations</i></a>. Cambridge University Press. p. 26. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-521-53551-9" title="Special:BookSources/978-0-521-53551-9"><bdi>978-0-521-53551-9</bdi></a><span class="reference-accessdate">. Retrieved <span class="nowrap">20 October</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Astronomy+Methods%3A+A+Physical+Approach+to+Astronomical+Observations&rft.pages=26&rft.pub=Cambridge+University+Press&rft.date=2004&rft.isbn=978-0-521-53551-9&rft.aulast=Bradt&rft.aufirst=Hale&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3Dhp7vyaGvhLMC%26pg%3DPA26&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-OhannesianStreeter2001-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-OhannesianStreeter2001_9-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOhannesianStreeter2001" class="citation book cs1">Ohannesian, Lena; Streeter, Anthony (2001). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=DwPb4wgqseYC&pg=PA187"><i>Handbook of Pharmaceutical Analysis</i></a>. CRC Press. p. 187. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-8247-4194-5" title="Special:BookSources/978-0-8247-4194-5"><bdi>978-0-8247-4194-5</bdi></a><span class="reference-accessdate">. Retrieved <span class="nowrap">20 October</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Handbook+of+Pharmaceutical+Analysis&rft.pages=187&rft.pub=CRC+Press&rft.date=2001&rft.isbn=978-0-8247-4194-5&rft.aulast=Ohannesian&rft.aufirst=Lena&rft.au=Streeter%2C+Anthony&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DDwPb4wgqseYC%26pg%3DPA187&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-AhluwaliaGoyal2000-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-AhluwaliaGoyal2000_10-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAhluwaliaGoyal2000" class="citation book cs1">Ahluwalia, V.K.; Goyal, Madhuri (2000). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=tJNJnn0M75MC&pg=PA110"><i>A Textbook of Organic Chemistry</i></a>. Narosa. p. 110. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-81-7319-159-6" title="Special:BookSources/978-81-7319-159-6"><bdi>978-81-7319-159-6</bdi></a><span class="reference-accessdate">. Retrieved <span class="nowrap">20 October</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=A+Textbook+of+Organic+Chemistry&rft.pages=110&rft.pub=Narosa&rft.date=2000&rft.isbn=978-81-7319-159-6&rft.aulast=Ahluwalia&rft.aufirst=V.K.&rft.au=Goyal%2C+Madhuri&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DtJNJnn0M75MC%26pg%3DPA110&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-Sliney1976-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-Sliney1976_11-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSlineyWangemannFranksWolbarsht1976" class="citation journal cs1">Sliney, David H.; Wangemann, Robert T.; Franks, James K.; Wolbarsht, Myron L. (1976). "Visual sensitivity of the eye to infrared laser radiation". <i><a href="/wiki/Journal_of_the_Optical_Society_of_America" title="Journal of the Optical Society of America">Journal of the Optical Society of America</a></i>. <b>66</b> (4): 339–341. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1976JOSA...66..339S">1976JOSA...66..339S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1364%2FJOSA.66.000339">10.1364/JOSA.66.000339</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/1262982">1262982</a>. <q>The foveal sensitivity to several near-infrared laser wavelengths was measured. It was found that the eye could respond to radiation at wavelengths at least as far as 1,064 nm. A continuous 1,064 nm laser source appeared red, but a 1,060 nm pulsed laser source appeared green, which suggests the presence of second harmonic generation in the retina.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Journal+of+the+Optical+Society+of+America&rft.atitle=Visual+sensitivity+of+the+eye+to+infrared+laser+radiation&rft.volume=66&rft.issue=4&rft.pages=339-341&rft.date=1976&rft_id=info%3Apmid%2F1262982&rft_id=info%3Adoi%2F10.1364%2FJOSA.66.000339&rft_id=info%3Abibcode%2F1976JOSA...66..339S&rft.aulast=Sliney&rft.aufirst=David+H.&rft.au=Wangemann%2C+Robert+T.&rft.au=Franks%2C+James+K.&rft.au=Wolbarsht%2C+Myron+L.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-LynchLivingston2001-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-LynchLivingston2001_12-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLynchLivingston2001" class="citation book cs1">Lynch, David K.; Livingston, William Charles (2001). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=4Abp5FdhskAC&pg=PA231"><i>Color and Light in Nature</i></a> (2nd ed.). Cambridge: Cambridge University Press. p. 231. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-521-77504-5" title="Special:BookSources/978-0-521-77504-5"><bdi>978-0-521-77504-5</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221008031821/https://books.google.com/books?id=4Abp5FdhskAC&pg=PA231">Archived</a> from the original on 8 October 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">12 October</span> 2013</span>. <q>Limits of the eye's overall range of sensitivity extends from about 310 to 1,050 nanometers</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Color+and+Light+in+Nature&rft.place=Cambridge&rft.pages=231&rft.edition=2nd&rft.pub=Cambridge+University+Press&rft.date=2001&rft.isbn=978-0-521-77504-5&rft.aulast=Lynch&rft.aufirst=David+K.&rft.au=Livingston%2C+William+Charles&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D4Abp5FdhskAC%26pg%3DPA231&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-Dash2009-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-Dash2009_13-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDashDash2009" class="citation book cs1">Dash, Madhab Chandra; Dash, Satya Prakash (2009). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=7mW4-us4Yg8C&pg=PA213"><i>Fundamentals of Ecology 3E</i></a>. Tata McGraw-Hill Education. p. 213. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-259-08109-5" title="Special:BookSources/978-1-259-08109-5"><bdi>978-1-259-08109-5</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221008031820/https://books.google.com/books?id=7mW4-us4Yg8C&pg=PA213">Archived</a> from the original on 8 October 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">18 October</span> 2013</span>. <q>Normally the human eye responds to light rays from 390 to 760 nm. This can be extended to a range of 310 to 1,050 nm under artificial conditions.</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Fundamentals+of+Ecology+3E&rft.pages=213&rft.pub=Tata+McGraw-Hill+Education&rft.date=2009&rft.isbn=978-1-259-08109-5&rft.aulast=Dash&rft.aufirst=Madhab+Chandra&rft.au=Dash%2C+Satya+Prakash&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D7mW4-us4Yg8C%26pg%3DPA213&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-Saidman1933-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-Saidman1933_14-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSaidman1933" class="citation journal cs1 cs1-prop-foreign-lang-source">Saidman, Jean (15 May 1933). <a rel="nofollow" class="external text" href="http://visualiseur.bnf.fr/ark:/12148/bpt6k3148d">"Sur la visibilité de l'ultraviolet jusqu'à la longueur d'onde 3130"</a> [The visibility of the ultraviolet to the wave length of 3130]. <i><a href="/wiki/Comptes_rendus_de_l%27Acad%C3%A9mie_des_sciences" class="mw-redirect" title="Comptes rendus de l'Académie des sciences">Comptes rendus de l'Académie des sciences</a></i> (in French). <b>196</b>: 1537–9. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20131024092515/http://visualiseur.bnf.fr/ark:/12148/bpt6k3148d">Archived</a> from the original on 24 October 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">21 October</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Comptes+rendus+de+l%27Acad%C3%A9mie+des+sciences&rft.atitle=Sur+la+visibilit%C3%A9+de+l%27ultraviolet+jusqu%27%C3%A0+la+longueur+d%27onde+3130&rft.volume=196&rft.pages=1537-9&rft.date=1933-05-15&rft.aulast=Saidman&rft.aufirst=Jean&rft_id=http%3A%2F%2Fvisualiseur.bnf.fr%2Fark%3A%2F12148%2Fbpt6k3148d&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-15"><span class="mw-cite-backlink"><b><a href="#cite_ref-15">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFOldfordMacKay2000" class="citation journal cs1">Oldford, R. W; MacKay, R. J (2000). <a rel="nofollow" class="external text" href="http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.ss%2F1009212817">"Scientific Method, Statistical Method and the Speed of Light"</a>. <i>Statistical Science</i>. <b>15</b> (3): 254–278. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1214%2Fss%2F1009212817">10.1214/ss/1009212817</a></span>. <a href="/wiki/MR_(identifier)" class="mw-redirect" title="MR (identifier)">MR</a> <a rel="nofollow" class="external text" href="https://mathscinet.ams.org/mathscinet-getitem?mr=1847825">1847825</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170324201543/http://projecteuclid.org/DPubS/Repository/1.0/Disseminate?view=body&id=pdf_1&handle=euclid.ss%2F1009212817">Archived</a> from the original on 24 March 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">21 August</span> 2008</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Statistical+Science&rft.atitle=Scientific+Method%2C+Statistical+Method+and+the+Speed+of+Light&rft.volume=15&rft.issue=3&rft.pages=254-278&rft.date=2000&rft_id=info%3Adoi%2F10.1214%2Fss%2F1009212817&rft_id=https%3A%2F%2Fmathscinet.ams.org%2Fmathscinet-getitem%3Fmr%3D1847825%23id-name%3DMR&rft.aulast=Oldford&rft.aufirst=R.+W&rft.au=MacKay%2C+R.+J&rft_id=http%3A%2F%2Fprojecteuclid.org%2FDPubS%2FRepository%2F1.0%2FDisseminate%3Fview%3Dbody%26id%3Dpdf_1%26handle%3Deuclid.ss%252F1009212817&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-EB1911-16"><span class="mw-cite-backlink">^ <a href="#cite_ref-EB1911_16-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-EB1911_16-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNewcomb1911" class="citation encyclopaedia cs1">Newcomb, Simon (1911). <span class="cs1-ws-icon" title="s:1911 Encyclopædia Britannica/Light"><a class="external text" href="https://en.wikisource.org/wiki/1911_Encyclop%C3%A6dia_Britannica/Light">"Light" </a></span>. In <a href="/wiki/Hugh_Chisholm" title="Hugh Chisholm">Chisholm, Hugh</a> (ed.). <i><a href="/wiki/Encyclop%C3%A6dia_Britannica_Eleventh_Edition" title="Encyclopædia Britannica Eleventh Edition">Encyclopædia Britannica</a></i>. Vol. 16 (11th ed.). Cambridge University Press. p. 624.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Light&rft.btitle=Encyclop%C3%A6dia+Britannica&rft.pages=624&rft.edition=11th&rft.pub=Cambridge+University+Press&rft.date=1911&rft.aulast=Newcomb&rft.aufirst=Simon&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-17"><span class="mw-cite-backlink"><b><a href="#cite_ref-17">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMichelson1927" class="citation journal cs1">Michelson, A.A. (January 1927). "Measurements of the velocity of light between Mount Wilson and Mount San Antonio". <i>Astrophysical Journal</i>. <b>65</b>: 1. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1927ApJ....65....1M">1927ApJ....65....1M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F143021">10.1086/143021</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Astrophysical+Journal&rft.atitle=Measurements+of+the+velocity+of+light+between+Mount+Wilson+and+Mount+San+Antonio&rft.volume=65&rft.pages=1&rft.date=1927-01&rft_id=info%3Adoi%2F10.1086%2F143021&rft_id=info%3Abibcode%2F1927ApJ....65....1M&rft.aulast=Michelson&rft.aufirst=A.A.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHarvard_News_Office2001" class="citation web cs1">Harvard News Office (24 January 2001). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20111028041346/http://www.news.harvard.edu/gazette/2001/01.24/01-stoplight.html">"Harvard Gazette: Researchers now able to stop, restart light"</a>. News.harvard.edu. Archived from <a rel="nofollow" class="external text" href="http://www.news.harvard.edu/gazette/2001/01.24/01-stoplight.html">the original</a> on 28 October 2011<span class="reference-accessdate">. Retrieved <span class="nowrap">8 November</span> 2011</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Harvard+Gazette%3A+Researchers+now+able+to+stop%2C+restart+light&rft.pub=News.harvard.edu&rft.date=2001-01-24&rft.au=Harvard+News+Office&rft_id=http%3A%2F%2Fwww.news.harvard.edu%2Fgazette%2F2001%2F01.24%2F01-stoplight.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBerns2019" class="citation book cs1">Berns, Roy S. (2019). <i>Billmeyer and Saltzman's Principles of Color Technology</i>. Fred W. Billmeyer, Max Saltzman (4th ed.). Hoboken, NJ: <a href="/wiki/Wiley_(publisher)" title="Wiley (publisher)">Wiley</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-1-119-36668-3" title="Special:BookSources/978-1-119-36668-3"><bdi>978-1-119-36668-3</bdi></a>. <a href="/wiki/OCLC_(identifier)" class="mw-redirect" title="OCLC (identifier)">OCLC</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/oclc/1080250734">1080250734</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Billmeyer+and+Saltzman%27s+Principles+of+Color+Technology&rft.place=Hoboken%2C+NJ&rft.edition=4th&rft.pub=Wiley&rft.date=2019&rft_id=info%3Aoclcnum%2F1080250734&rft.isbn=978-1-119-36668-3&rft.aulast=Berns&rft.aufirst=Roy+S.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://thulescientific.com/LYNCH%20%26%20Soffer%20OPN%201999.pdf">"Spectrum and the Color Sensitivity of the Eye"</a> <span class="cs1-format">(PDF)</span>. <i>Thulescientific.com</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20100705070506/http://thulescientific.com/LYNCH%20%26%20Soffer%20OPN%201999.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 5 July 2010<span class="reference-accessdate">. Retrieved <span class="nowrap">29 August</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Thulescientific.com&rft.atitle=Spectrum+and+the+Color+Sensitivity+of+the+Eye&rft_id=http%3A%2F%2Fthulescientific.com%2FLYNCH%2520%2526%2520Soffer%2520OPN%25201999.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://rredc.nrel.gov/solar/spectra/am1.5/">"Reference Solar Spectral Irradiance: Air Mass 1.5"</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20190512190812/https://rredc.nrel.gov/solar//spectra/am1.5/">Archived</a> from the original on 12 May 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">12 November</span> 2009</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Reference+Solar+Spectral+Irradiance%3A+Air+Mass+1.5&rft_id=http%3A%2F%2Frredc.nrel.gov%2Fsolar%2Fspectra%2Fam1.5%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-22"><span class="mw-cite-backlink"><b><a href="#cite_ref-22">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFTang2009" class="citation journal cs1">Tang, Hong (1 October 2009). "May The Force of Light Be With You". <i>IEEE Spectrum</i>. <b>46</b> (10): 46–51. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1109%2FMSPEC.2009.5268000">10.1109/MSPEC.2009.5268000</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:7928030">7928030</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=IEEE+Spectrum&rft.atitle=May+The+Force+of+Light+Be+With+You&rft.volume=46&rft.issue=10&rft.pages=46-51&rft.date=2009-10-01&rft_id=info%3Adoi%2F10.1109%2FMSPEC.2009.5268000&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A7928030%23id-name%3DS2CID&rft.aulast=Tang&rft.aufirst=Hong&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-23"><span class="mw-cite-backlink"><b><a href="#cite_ref-23">^</a></b></span> <span class="reference-text">See, for example, <a rel="nofollow" class="external text" href="http://www.eng.yale.edu/tanglab/research.htm">nano-opto-mechanical systems research at Yale University</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20100625042036/http://www.eng.yale.edu/tanglab/research.htm">Archived</a> 25 June 2010 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a>.</span> </li> <li id="cite_note-24"><span class="mw-cite-backlink"><b><a href="#cite_ref-24">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSvitil2004" class="citation web cs1">Svitil, Kathy A. (5 February 2004). <a rel="nofollow" class="external text" href="http://discovermagazine.com/2004/feb/asteroids-get-spun-by-the-sun/">"Asteroids Get Spun By the Sun"</a>. <i>Discover Magazine</i>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20121009045611/http://discovermagazine.com/2004/feb/asteroids-get-spun-by-the-sun/">Archived</a> from the original on 9 October 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">8 May</span> 2007</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Discover+Magazine&rft.atitle=Asteroids+Get+Spun+By+the+Sun&rft.date=2004-02-05&rft.aulast=Svitil&rft.aufirst=Kathy+A.&rft_id=http%3A%2F%2Fdiscovermagazine.com%2F2004%2Ffeb%2Fasteroids-get-spun-by-the-sun%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-25"><span class="mw-cite-backlink"><b><a href="#cite_ref-25">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.nasa.gov/vision/universe/roboticexplorers/solar_sails.html">"Solar Sails Could Send Spacecraft 'Sailing' Through Space"</a>. <i>NASA</i>. 31 August 2004. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20121021035846/http://www.nasa.gov/vision/universe/roboticexplorers/solar_sails.html">Archived</a> from the original on 21 October 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">30 May</span> 2008</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=NASA&rft.atitle=Solar+Sails+Could+Send+Spacecraft+%27Sailing%27+Through+Space&rft.date=2004-08-31&rft_id=http%3A%2F%2Fwww.nasa.gov%2Fvision%2Funiverse%2Froboticexplorers%2Fsolar_sails.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-26"><span class="mw-cite-backlink"><b><a href="#cite_ref-26">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.nasa.gov/centers/marshall/news/news/releases/2004/04-208.html">"NASA team successfully deploys two solar sail systems"</a>. <i>NASA</i>. 9 August 2004. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20120614013757/http://www.nasa.gov/centers/marshall/news/news/releases/2004/04-208.html">Archived</a> from the original on 14 June 2012<span class="reference-accessdate">. Retrieved <span class="nowrap">30 May</span> 2008</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=NASA&rft.atitle=NASA+team+successfully+deploys+two+solar+sail+systems&rft.date=2004-08-09&rft_id=http%3A%2F%2Fwww.nasa.gov%2Fcenters%2Fmarshall%2Fnews%2Fnews%2Freleases%2F2004%2F04-208.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-27"><span class="mw-cite-backlink"><b><a href="#cite_ref-27">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLebedew1901" class="citation journal cs1"><a href="/wiki/Pyotr_Lebedev" title="Pyotr Lebedev">Lebedew, P.</a> (1901). <a rel="nofollow" class="external text" href="https://zenodo.org/record/1424005">"Untersuchungen über die Druckkräfte des Lichtes"</a>. <i>Ann. Phys</i>. <b>6</b> (11): 433–458. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1901AnP...311..433L">1901AnP...311..433L</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1002%2Fandp.19013111102">10.1002/andp.19013111102</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20220606184159/https://zenodo.org/record/1424005">Archived</a> from the original on 6 June 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">29 July</span> 2022</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Ann.+Phys.&rft.atitle=Untersuchungen+%C3%BCber+die+Druckkr%C3%A4fte+des+Lichtes&rft.volume=6&rft.issue=11&rft.pages=433-458&rft.date=1901&rft_id=info%3Adoi%2F10.1002%2Fandp.19013111102&rft_id=info%3Abibcode%2F1901AnP...311..433L&rft.aulast=Lebedew&rft.aufirst=P.&rft_id=https%3A%2F%2Fzenodo.org%2Frecord%2F1424005&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-28"><span class="mw-cite-backlink"><b><a href="#cite_ref-28">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFNicholsHull1903" class="citation journal cs1">Nichols, E.F; Hull, G.F. (1903). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=8n8OAAAAIAAJ&q=torsion+balance+radiation&pg=RA5-PA327">"The Pressure due to Radiation"</a>. <i>The Astrophysical Journal</i>. <b>17</b> (5): 315–351. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1903ApJ....17..315N">1903ApJ....17..315N</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1086%2F141035">10.1086/141035</a></span>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221008031820/https://books.google.com/books?id=8n8OAAAAIAAJ&q=torsion+balance+radiation&pg=RA5-PA327">Archived</a> from the original on 8 October 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">15 November</span> 2020</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=The+Astrophysical+Journal&rft.atitle=The+Pressure+due+to+Radiation&rft.volume=17&rft.issue=5&rft.pages=315-351&rft.date=1903&rft_id=info%3Adoi%2F10.1086%2F141035&rft_id=info%3Abibcode%2F1903ApJ....17..315N&rft.aulast=Nichols&rft.aufirst=E.F&rft.au=Hull%2C+G.F.&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3D8n8OAAAAIAAJ%26q%3Dtorsion%2Bbalance%2Bradiation%26pg%3DRA5-PA327&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-29"><span class="mw-cite-backlink"><b><a href="#cite_ref-29">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFEinstein,_A.1989" class="citation book cs1">Einstein, A. (1989) [1909]. "Über die Entwicklung unserer Anschauungen über das Wesen und die Konstitution der Strahlung" [On the development of our views concerning the nature and constitution of radiation]. <i>The Collected Papers of Albert Einstein</i>. Vol. 2. Princeton, New Jersey: Princeton University Press. p. 391.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=%C3%9Cber+die+Entwicklung+unserer+Anschauungen+%C3%BCber+das+Wesen+und+die+Konstitution+der+Strahlung&rft.btitle=The+Collected+Papers+of+Albert+Einstein&rft.place=Princeton%2C+New+Jersey&rft.pages=391&rft.pub=Princeton+University+Press&rft.date=1989&rft.au=Einstein%2C+A.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-30"><span class="mw-cite-backlink"><b><a href="#cite_ref-30">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAntognozziBerminghamHarnimanSimpson2016" class="citation journal cs1">Antognozzi, M.; Bermingham, C. R.; Harniman, R. L.; Simpson, S.; Senior, J.; Hayward, R.; Hoerber, H.; Dennis, M. R.; Bekshaev, A. Y. (August 2016). "Direct measurements of the extraordinary optical momentum and transverse spin-dependent force using a nano-cantilever". <i>Nature Physics</i>. <b>12</b> (8): 731–735. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1506.04248">1506.04248</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2016NatPh..12..731A">2016NatPh..12..731A</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1038%2Fnphys3732">10.1038/nphys3732</a>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1745-2473">1745-2473</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:52226942">52226942</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature+Physics&rft.atitle=Direct+measurements+of+the+extraordinary+optical+momentum+and+transverse+spin-dependent+force+using+a+nano-cantilever&rft.volume=12&rft.issue=8&rft.pages=731-735&rft.date=2016-08&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A52226942%23id-name%3DS2CID&rft_id=info%3Abibcode%2F2016NatPh..12..731A&rft_id=info%3Aarxiv%2F1506.04248&rft.issn=1745-2473&rft_id=info%3Adoi%2F10.1038%2Fnphys3732&rft.aulast=Antognozzi&rft.aufirst=M.&rft.au=Bermingham%2C+C.+R.&rft.au=Harniman%2C+R.+L.&rft.au=Simpson%2C+S.&rft.au=Senior%2C+J.&rft.au=Hayward%2C+R.&rft.au=Hoerber%2C+H.&rft.au=Dennis%2C+M.+R.&rft.au=Bekshaev%2C+A.+Y.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-31"><span class="mw-cite-backlink"><b><a href="#cite_ref-31">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFSingh2009" class="citation book cs1">Singh, S. (2009). <i>Fundamentals of Optical Engineering</i>. Discovery Publishing House. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-8183564366" title="Special:BookSources/978-8183564366"><bdi>978-8183564366</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Fundamentals+of+Optical+Engineering&rft.pub=Discovery+Publishing+House&rft.date=2009&rft.isbn=978-8183564366&rft.aulast=Singh&rft.aufirst=S.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-32"><span class="mw-cite-backlink"><b><a href="#cite_ref-32">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFO'ConnorRobertson2002" class="citation web cs1">O'Connor, J J; Robertson, E F (August 2002). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20170319180859/http://www-groups.dcs.st-and.ac.uk/history/HistTopics/Light_1.html">"Light through the ages: Ancient Greece to Maxwell"</a>. Archived from <a rel="nofollow" class="external text" href="http://www-groups.dcs.st-and.ac.uk/history/HistTopics/Light_1.html">the original</a> on 19 March 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">20 February</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Light+through+the+ages%3A+Ancient+Greece+to+Maxwell&rft.date=2002-08&rft.aulast=O%27Connor&rft.aufirst=J+J&rft.au=Robertson%2C+E+F&rft_id=http%3A%2F%2Fwww-groups.dcs.st-and.ac.uk%2Fhistory%2FHistTopics%2FLight_1.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-33"><span class="mw-cite-backlink"><b><a href="#cite_ref-33">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPtolemy_and_A._Mark_Smith1996" class="citation book cs1">Ptolemy and A. Mark Smith (1996). <i>Ptolemy's Theory of Visual Perception: An English Translation of the Optics with Introduction and Commentary</i>. Diane Publishing. p. 23. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-87169-862-9" title="Special:BookSources/978-0-87169-862-9"><bdi>978-0-87169-862-9</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Ptolemy%27s+Theory+of+Visual+Perception%3A+An+English+Translation+of+the+Optics+with+Introduction+and+Commentary&rft.pages=23&rft.pub=Diane+Publishing&rft.date=1996&rft.isbn=978-0-87169-862-9&rft.au=Ptolemy+and+A.+Mark+Smith&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-sifuae.com-34"><span class="mw-cite-backlink">^ <a href="#cite_ref-sifuae.com_34-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-sifuae.com_34-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-sifuae.com_34-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20150530101227/http://www.sifuae.com/sif/wp-content/uploads/2015/04/Shastra-Pratibha-2015-Seniors-Booklet.pdf">"Shastra Pratibha 2015 Seniors Booklet"</a> <span class="cs1-format">(PDF)</span>. <i>Sifuae.com</i>. Archived from <a rel="nofollow" class="external text" href="http://www.sifuae.com/sif/wp-content/uploads/2015/04/Shastra-Pratibha-2015-Seniors-Booklet.pdf">the original</a> <span class="cs1-format">(PDF)</span> on 30 May 2015<span class="reference-accessdate">. Retrieved <span class="nowrap">29 August</span> 2017</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Sifuae.com&rft.atitle=Shastra+Pratibha+2015+Seniors+Booklet&rft_id=http%3A%2F%2Fwww.sifuae.com%2Fsif%2Fwp-content%2Fuploads%2F2015%2F04%2FShastra-Pratibha-2015-Seniors-Booklet.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-Theories_of_light-35"><span class="mw-cite-backlink">^ <a href="#cite_ref-Theories_of_light_35-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Theories_of_light_35-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><i>Theories of light, from Descartes to Newton</i> A.I. Sabra CUP Archive,1981 p. 48 <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-521-28436-3" title="Special:BookSources/978-0-521-28436-3">978-0-521-28436-3</a></span> </li> <li id="cite_note-36"><span class="mw-cite-backlink"><b><a href="#cite_ref-36">^</a></b></span> <span class="reference-text">Fokko Jan Dijksterhuis, <a rel="nofollow" class="external text" href="https://books.google.com/books?id=cPFevyomPUIC">Lenses and Waves: Christiaan Huygens and the Mathematical Science of Optics in the 17th Century</a>, Kluwer Academic Publishers, 2004, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/1-4020-2697-8" title="Special:BookSources/1-4020-2697-8">1-4020-2697-8</a></span> </li> <li id="cite_note-37"><span class="mw-cite-backlink"><b><a href="#cite_ref-37">^</a></b></span> <span class="reference-text">James R. Hofmann, <i>André-Marie Ampère: Enlightenment and Electrodynamics</i>, Cambridge University Press, 1996, p. 222.</span> </li> <li id="cite_note-38"><span class="mw-cite-backlink"><b><a href="#cite_ref-38">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDavid_CassidyGerald_HoltonJames_Rutherford2002" class="citation book cs1">David Cassidy; Gerald Holton; James Rutherford (2002). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=rpQo7f9F1xUC&pg=PA382"><i>Understanding Physics</i></a>. Birkhäuser. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-387-98756-9" title="Special:BookSources/978-0-387-98756-9"><bdi>978-0-387-98756-9</bdi></a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20221008031820/https://books.google.com/books?id=rpQo7f9F1xUC&pg=PA382">Archived</a> from the original on 8 October 2022<span class="reference-accessdate">. Retrieved <span class="nowrap">15 November</span> 2020</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Understanding+Physics&rft.pub=Birkh%C3%A4user&rft.date=2002&rft.isbn=978-0-387-98756-9&rft.au=David+Cassidy&rft.au=Gerald+Holton&rft.au=James+Rutherford&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DrpQo7f9F1xUC%26pg%3DPA382&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-LongairMalcolm-39"><span class="mw-cite-backlink">^ <a href="#cite_ref-LongairMalcolm_39-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-LongairMalcolm_39-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLongair2003" class="citation book cs1">Longair, Malcolm (2003). <span class="id-lock-limited" title="Free access subject to limited trial, subscription normally required"><a rel="nofollow" class="external text" href="https://archive.org/details/theoreticalconce00mslo"><i>Theoretical Concepts in Physics</i></a></span>. p. <a rel="nofollow" class="external text" href="https://archive.org/details/theoreticalconce00mslo/page/n106">87</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Theoretical+Concepts+in+Physics&rft.pages=87&rft.date=2003&rft.aulast=Longair&rft.aufirst=Malcolm&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Ftheoreticalconce00mslo&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-40"><span class="mw-cite-backlink"><b><a href="#cite_ref-40">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFCassidy2002" class="citation book cs1">Cassidy, D (2002). <i>Understanding Physics</i>. Springer Verlag New York.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Understanding+Physics&rft.pub=Springer+Verlag+New+York&rft.date=2002&rft.aulast=Cassidy&rft.aufirst=D&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> <li id="cite_note-41"><span class="mw-cite-backlink"><b><a href="#cite_ref-41">^</a></b></span> <span class="reference-text"><span style="position:relative; top: -2px;"><span typeof="mw:File"><a href="/wiki/Open_access" title="open access publication – free to read"><img alt="Open access icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/7/77/Open_Access_logo_PLoS_transparent.svg/9px-Open_Access_logo_PLoS_transparent.svg.png" decoding="async" width="9" height="14" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/77/Open_Access_logo_PLoS_transparent.svg/14px-Open_Access_logo_PLoS_transparent.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/77/Open_Access_logo_PLoS_transparent.svg/18px-Open_Access_logo_PLoS_transparent.svg.png 2x" data-file-width="640" data-file-height="1000" /></a></span></span> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBarrow1962" class="citation book cs1">Barrow, Gordon M. (1962). <a rel="nofollow" class="external text" href="https://archive.org/details/IntroductionToMolecularSpectroscopy"><i>Introduction to Molecular Spectroscopy</i></a> <span class="cs1-format">(Scanned PDF)</span>. McGraw-Hill. <a href="/wiki/LCCN_(identifier)" class="mw-redirect" title="LCCN (identifier)">LCCN</a> <a rel="nofollow" class="external text" href="https://lccn.loc.gov/62-12478">62-12478</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Introduction+to+Molecular+Spectroscopy&rft.pub=McGraw-Hill&rft.date=1962&rft_id=info%3Alccn%2F62-12478&rft.aulast=Barrow&rft.aufirst=Gordon+M.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2FIntroductionToMolecularSpectroscopy&rfr_id=info%3Asid%2Fen.wikipedia.org%3ALight" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2></div> <ul><li><span class="noviewer" typeof="mw:File"><a href="/wiki/File:Commons-logo.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/12px-Commons-logo.svg.png" decoding="async" width="12" height="16" class="mw-file-element" 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title="Particle accelerator">Particle accelerators</a></li> <li><a href="/wiki/Radionuclide" title="Radionuclide">Radioactive materials</a></li> <li><a href="/wiki/X-ray" title="X-ray">X-ray</a></li></ul> </div></td></tr><tr><td colspan="2" class="navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Earth%27s_energy_budget" title="Earth's energy budget">Earth's energy budget</a></li> <li><a href="/wiki/Electromagnetic_radiation" title="Electromagnetic radiation">Electromagnetic radiation</a></li> <li><a href="/wiki/Synchrotron_radiation" title="Synchrotron radiation">Synchrotron radiation</a></li> <li><a href="/wiki/Thermal_radiation" title="Thermal radiation">Thermal radiation</a></li> <li><a href="/wiki/Black-body_radiation" title="Black-body radiation">Black-body radiation</a></li> <li><a href="/wiki/Particle_radiation" title="Particle radiation">Particle radiation</a></li> <li><a href="/wiki/Gravitational_radiation" class="mw-redirect" title="Gravitational radiation">Gravitational radiation</a></li> <li><a href="/wiki/Cosmic_background_radiation" title="Cosmic background radiation">Cosmic background radiation</a></li> <li><a href="/wiki/Cherenkov_radiation" title="Cherenkov radiation">Cherenkov radiation</a></li> <li><a href="/wiki/Askaryan_radiation" title="Askaryan radiation">Askaryan radiation</a></li> <li><a href="/wiki/Bremsstrahlung" title="Bremsstrahlung">Bremsstrahlung</a></li> <li><a href="/wiki/Unruh_radiation" class="mw-redirect" title="Unruh radiation">Unruh radiation</a></li> <li><a href="/wiki/Dark_radiation" title="Dark radiation">Dark radiation</a></li> <li><a href="/wiki/Radiation_exposure" title="Radiation exposure">Radiation exposure</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Radiation <br />and health</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Radiation syndrome <ul><li><a href="/wiki/Acute_radiation_syndrome" title="Acute radiation syndrome">acute</a></li> <li><a href="/wiki/Chronic_radiation_syndrome" title="Chronic radiation syndrome">chronic</a></li></ul></li> <li><a href="/wiki/Health_physics" title="Health physics">Health physics</a></li> <li><a href="/wiki/Dosimetry" title="Dosimetry">Dosimetry</a></li> <li><a href="/wiki/Electromagnetic_radiation_and_health" title="Electromagnetic radiation and health">Electromagnetic radiation and health</a></li> <li><a href="/wiki/Laser_safety" title="Laser safety">Laser safety</a></li> <li><a href="/wiki/Lasers_and_aviation_safety" title="Lasers and aviation safety">Lasers and aviation safety</a></li> <li><a href="/wiki/Medical_radiography" class="mw-redirect" title="Medical radiography">Medical radiography</a></li> <li><a href="/wiki/Radiation_protection" title="Radiation protection">Radiation protection</a></li> <li><a href="/wiki/Radiation_therapy" title="Radiation therapy">Radiation therapy</a></li> <li><a href="/wiki/Radiation_damage" title="Radiation damage">Radiation damage</a></li> <li><a href="/wiki/Radioactivity_in_the_life_sciences" title="Radioactivity in the life sciences">Radioactivity in the life sciences</a></li> <li><a href="/wiki/Radioactive_contamination" title="Radioactive contamination">Radioactive contamination</a></li> <li><a href="/wiki/Radiobiology" title="Radiobiology">Radiobiology</a></li> <li><a href="/wiki/Sievert" title="Sievert">Biological dose units and quantities</a></li> <li><a href="/wiki/Wireless_device_radiation_and_health" title="Wireless device radiation and health">Wireless device radiation and health</a></li> <li><a href="/wiki/Wireless_electronic_devices_and_health" class="mw-redirect" title="Wireless electronic devices and health">Wireless electronic devices and health</a></li> <li><a href="/wiki/Heat_transfer" title="Heat transfer">Radiation heat-transfer</a></li> <li><a href="/wiki/Linear_energy_transfer" title="Linear energy transfer">Linear energy transfer</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Radiation incidents</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_civilian_radiation_accidents" title="List of civilian radiation accidents">List of civilian radiation accidents</a></li> <li><a href="/wiki/1996_San_Juan_de_Dios_radiotherapy_accident" title="1996 San Juan de Dios radiotherapy accident">1996 Costa Rica accident</a></li> <li><a href="/wiki/Goi%C3%A2nia_accident" title="Goiânia accident">1987 Goiânia accident</a></li> <li><a href="/wiki/1984_Moroccan_radiation_accident" title="1984 Moroccan radiation accident">1984 Moroccan accident</a></li> <li><a href="/wiki/1990_Clinic_of_Zaragoza_radiotherapy_accident" class="mw-redirect" title="1990 Clinic of Zaragoza radiotherapy accident">1990 Zaragoza accident</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Related articles</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Half-life" title="Half-life">Half-life</a></li> <li><a href="/wiki/Nuclear_physics" title="Nuclear physics">Nuclear physics</a></li> <li><a href="/wiki/Radioactive_source" title="Radioactive source">Radioactive source</a></li> <li><a href="/wiki/Radiation_hardening" title="Radiation hardening">Radiation hardening</a></li> <li><a href="/wiki/Havana_syndrome" title="Havana syndrome">Havana syndrome</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div><div role="note" class="hatnote navigation-not-searchable selfref">See also the categories <a href="/wiki/Category:Radiation_effects" title="Category:Radiation effects">Radiation effects</a>, <a href="/wiki/Category:Radioactivity" title="Category:Radioactivity">Radioactivity</a>, <a href="/wiki/Category:Radiobiology" title="Category:Radiobiology">Radiobiology</a>, and <a href="/wiki/Category:Radiation_protection" title="Category:Radiation protection">Radiation protection</a></div></div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Colour_topics" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Color_topics" title="Template:Color topics"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Color_topics" title="Template talk:Color topics"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Color_topics" title="Special:EditPage/Template:Color topics"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Colour_topics" style="font-size:114%;margin:0 4em"><a href="/wiki/Color" title="Color">Colour</a> topics</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Color_science" title="Color science">Colour science</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Colour physics</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Electromagnetic_spectrum" title="Electromagnetic spectrum">Electromagnetic spectrum</a> <ul><li><a class="mw-selflink selflink">Light</a></li> <li><a href="/wiki/Rainbow" title="Rainbow">Rainbow</a></li> <li><a href="/wiki/Visible_spectrum" title="Visible spectrum">Visible</a></li></ul></li> <li><a href="/wiki/Spectral_color" title="Spectral color">Spectral colours</a></li> <li><a href="/wiki/Chromophore" title="Chromophore">Chromophore</a> <ul><li><a href="/wiki/Structural_colouration" class="mw-redirect" title="Structural colouration">Structural colouration</a></li> <li><a href="/wiki/Animal_colouration" class="mw-redirect" title="Animal colouration">Animal colouration</a></li></ul></li> <li><a href="/wiki/Colour_of_chemicals" class="mw-redirect" title="Colour of chemicals">Colour of chemicals</a> <ul><li><a href="/wiki/Color_of_water" title="Color of water">Water</a></li></ul></li> <li><a href="/wiki/Spectral_power_distribution" title="Spectral power distribution">Spectral power distribution</a></li> <li><a href="/wiki/Colorimetry" title="Colorimetry">Colorimetry</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Color_vision" title="Color vision">Colour perception</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Chromesthesia" title="Chromesthesia">Chromesthesia</a> <ul><li><a href="/wiki/Sonochromatism" title="Sonochromatism">Sonochromatism</a></li></ul></li> <li><a href="/wiki/Colour_blindness" class="mw-redirect" title="Colour blindness">Colour blindness</a> <ul><li><a href="/wiki/Achromatopsia" title="Achromatopsia">Achromatopsia</a></li> <li><a href="/wiki/Dichromacy" title="Dichromacy">Dichromacy</a></li></ul></li> <li><a href="/wiki/Colour_calibration" class="mw-redirect" title="Colour calibration">Colour calibration</a></li> <li><a href="/wiki/Colour_constancy" class="mw-redirect" title="Colour constancy">Colour constancy</a></li> <li><a href="/wiki/Colour_task" class="mw-redirect" title="Colour task">Colour task</a> <ul><li><a href="/wiki/Colour_code" class="mw-redirect" title="Colour code">Colour code</a></li></ul></li> <li><a href="/wiki/Colour_temperature" class="mw-redirect" title="Colour temperature">Colour temperature</a></li> <li><a href="/wiki/Colour_vision_test" class="mw-redirect" title="Colour vision test">Colour vision test</a></li> <li><a href="/wiki/Evolution_of_colour_vision" class="mw-redirect" title="Evolution of colour vision">Evolution of colour vision</a></li> <li><a href="/wiki/Impossible_colour" class="mw-redirect" title="Impossible colour">Impossible colours</a></li> <li><a href="/wiki/Metamerism_(color)" title="Metamerism (color)">Metamerism</a></li> <li><a href="/wiki/Opponent_process" title="Opponent process">Opponent process</a> <ul><li><a href="/wiki/Afterimage" title="Afterimage">Afterimage</a></li> <li><a href="/wiki/Unique_hues" title="Unique hues">Unique hues</a></li></ul></li> <li><a href="/wiki/Tetrachromacy" title="Tetrachromacy">Tetrachromacy</a></li> <li><i><a href="/wiki/The_dress" title="The dress">The dress</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Colour_psychology" class="mw-redirect" title="Colour psychology">Colour psychology</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Colour_symbolism" class="mw-redirect" title="Colour symbolism">Colour symbolism</a></li> <li><a href="/wiki/Colour_preferences" class="mw-redirect" title="Colour preferences">Colour preferences</a></li> <li><a href="/wiki/L%C3%BCscher_colour_test" class="mw-redirect" title="Lüscher colour test">Lüscher colour test</a></li> <li><a href="/wiki/Kruithof_curve" title="Kruithof curve">Kruithof curve</a></li> <li><a href="/wiki/Political_colour" title="Political colour">Political colour</a></li> <li><a href="/wiki/National_colours" title="National colours">National colours</a></li> <li><a href="/wiki/Chromophobia" title="Chromophobia">Chromophobia</a></li> <li><a href="/wiki/Chromotherapy" title="Chromotherapy">Chromotherapy</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Colour_reproduction" class="mw-redirect" title="Colour reproduction">Colour reproduction</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Colour_photography" class="mw-redirect" title="Colour photography">Colour photography</a> <ul><li><a href="/wiki/Colour_balance" class="mw-redirect" title="Colour balance">Colour balance</a></li> <li><a href="/wiki/Colour_cast" title="Colour cast">Colour cast</a></li></ul></li> <li><a href="/wiki/Digital_image_processing" title="Digital image processing">Digital image processing</a></li> <li><a href="/wiki/Colour_management" class="mw-redirect" title="Colour management">Colour management</a></li> <li><a href="/wiki/Colour_printing" class="mw-redirect" title="Colour printing">Colour printing</a> <ul><li><a href="/wiki/Multi-primary_colour_display" class="mw-redirect" title="Multi-primary colour display">Multi-primary colour display</a></li> <li><a href="/wiki/Quattron" title="Quattron">Quattron</a></li></ul></li> <li><a href="/wiki/Colour_model" class="mw-redirect" title="Colour model">Colour model</a> <ul><li><a href="/wiki/Additive_color" title="Additive color">additive</a> <ul><li><a href="/wiki/RGB" class="mw-redirect" title="RGB">RGB</a></li></ul></li> <li><a href="/wiki/Subtractive_color" title="Subtractive color">subtractive</a> <ul><li><a href="/wiki/CMYK" class="mw-redirect" title="CMYK">CMYK</a></li></ul></li></ul></li> <li><a href="/wiki/Colour_space" class="mw-redirect" title="Colour space">Colour space</a></li> <li><a href="/wiki/Colour_mapping" class="mw-redirect" title="Colour mapping">Colour mapping</a></li></ul> </div></td></tr></tbody></table><div></div></td><td class="noviewer navbox-image" rowspan="6" style="width:1px;padding:0 0 0 2px"><div><span typeof="mw:File"><a href="/wiki/File:RGB_color_wheel.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/56/RGB_color_wheel.svg/100px-RGB_color_wheel.svg.png" decoding="async" width="100" height="83" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/56/RGB_color_wheel.svg/150px-RGB_color_wheel.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/56/RGB_color_wheel.svg/200px-RGB_color_wheel.svg.png 2x" data-file-width="600" data-file-height="500" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Philosophy_of_color" title="Philosophy of color">Colour<br />philosophy</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Colour_scheme" class="mw-redirect" title="Colour scheme">Colour scheme</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Color_picker" title="Color picker">Colour tool</a> <ul><li><a href="/wiki/Monochromatic_colours" class="mw-redirect" title="Monochromatic colours">Monochromatic colours</a> <ul><li><a href="/wiki/Black-and-white" title="Black-and-white">black-and-white</a></li></ul></li> <li><a href="/wiki/Complementary_colours" class="mw-redirect" title="Complementary colours">Complementary colours</a></li> <li><a href="/wiki/Analogous_colours" class="mw-redirect" title="Analogous colours">Analogous colours</a></li> <li><a href="/wiki/Grey" title="Grey">Achromatic colours (Neutral)</a></li> <li><a href="/wiki/Polychrome" title="Polychrome">Polychromatic colours</a></li></ul></li> <li><a href="/wiki/Light-on-dark_color_scheme" title="Light-on-dark color scheme">Light-on-dark</a></li> <li><a href="/wiki/Web_colours" class="mw-redirect" title="Web colours">Web colours</a></li> <li><a href="/wiki/Tincture_(heraldry)" title="Tincture (heraldry)">Tinctures in heraldry</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Colour_theory" class="mw-redirect" title="Colour theory">Colour theory</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Colour_mixing" class="mw-redirect" title="Colour mixing">Colour mixing</a> <ul><li><a href="/wiki/Primary_colour" class="mw-redirect" title="Primary colour">Primary colour</a></li> <li><a href="/wiki/Secondary_colour" class="mw-redirect" title="Secondary colour">Secondary colour</a></li></ul></li> <li><a href="/wiki/Chromaticity" title="Chromaticity">Chromaticity</a></li> <li><a href="/wiki/Colour_solid" class="mw-redirect" title="Colour solid">Colour solid</a></li> <li><a href="/wiki/Colour_wheel" class="mw-redirect" title="Colour wheel">Colour wheel</a></li> <li><a href="/wiki/Colour_triangle" class="mw-redirect" title="Colour triangle">Colour triangle</a></li> <li><a href="/wiki/Colour_analysis" class="mw-redirect" title="Colour analysis">Colour analysis</a> (fashion)</li> <li><a href="/wiki/Colour_realism_(art_style)" class="mw-redirect" title="Colour realism (art style)">Colour realism (art style)</a></li> <li><i><a href="/wiki/On_Vision_and_Colours" title="On Vision and Colours">On Vision and Colours</a></i> (Schopenhauer)</li> <li><i><a href="/wiki/Theory_of_Colours" title="Theory of Colours">Theory of Colours</a></i> (Goethe)</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Colour_term" class="mw-redirect" title="Colour term">Colour terms</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Color_term#Basic_color_terms" title="Color term">Basic terms</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Blue" title="Blue">Blue</a></li> <li><a href="/wiki/Green" title="Green">Green</a></li> <li><a href="/wiki/Red" title="Red">Red</a></li> <li><a href="/wiki/Yellow" title="Yellow">Yellow</a></li> <li><a href="/wiki/Pink" title="Pink">Pink</a></li> <li><a href="/wiki/Purple" title="Purple">Purple</a></li> <li><a href="/wiki/Orange_(colour)" title="Orange (colour)">Orange</a></li> <li><a href="/wiki/Black" title="Black">Black</a></li> <li><a href="/wiki/Grey" title="Grey">Grey</a></li> <li><a href="/wiki/White" title="White">White</a></li> <li><a href="/wiki/Brown" title="Brown">Brown</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Category:Color_in_culture" title="Category:Color in culture">Cultural differences</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Linguistic_relativity_and_the_colour_naming_debate" class="mw-redirect" title="Linguistic relativity and the colour naming debate">Linguistic relativity and the colour naming debate</a> <ul><li><a href="/wiki/Blue%E2%80%93green_distinction_in_language" title="Blue–green distinction in language">Blue–green distinction in language</a></li></ul></li> <li>Colour history <ul><li><a href="/wiki/Black-and-white_dualism" title="Black-and-white dualism">Black-and-white dualism</a></li> <li><a href="/wiki/Blue_in_culture" title="Blue in culture">Blue in culture</a></li> <li><a href="/wiki/Colour_in_Chinese_culture" class="mw-redirect" title="Colour in Chinese culture">Colour in Chinese culture</a></li> <li><a href="/wiki/Traditional_colours_of_Japan" class="mw-redirect" title="Traditional colours of Japan">Traditional colours of Japan</a></li> <li><a href="/wiki/Human_skin_colour" class="mw-redirect" title="Human skin colour">Human skin colour</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Colour dimensions</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hue" title="Hue">Hue</a> <ul><li><a href="/wiki/Dichromatism" title="Dichromatism">Dichromatism</a></li></ul></li> <li><a href="/wiki/Colourfulness" class="mw-redirect" title="Colourfulness">Colourfulness</a> <ul><li><a href="/wiki/Pastel_(color)" title="Pastel (color)">Pastel colours</a></li></ul></li> <li><a href="/wiki/Luminance" title="Luminance">Luminance</a> <ul><li><a href="/wiki/Lightness" title="Lightness">Lightness</a></li> <li><a href="/wiki/Darkness" title="Darkness">Darkness</a></li> <li><a href="/wiki/Brightness" title="Brightness">Brightness</a></li> <li><a href="/wiki/Iridescence" title="Iridescence">Iridescence</a></li> <li><a href="/wiki/Fluorescence" title="Fluorescence">Fluorescence</a></li></ul></li> <li><a href="/wiki/Grayscale" title="Grayscale">Grayscale</a></li> <li><a href="/wiki/Tint,_shade_and_tone" title="Tint, shade and tone">Tint, shade and tone</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Colour<br />organisations</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Pantone" title="Pantone">Pantone</a></li> <li><a href="/wiki/Color_Marketing_Group" title="Color Marketing Group">Color Marketing Group</a></li> <li><a href="/wiki/Color_Association_of_the_United_States" title="Color Association of the United States">Color Association of the United States</a></li> <li><a href="/wiki/International_Colour_Authority" title="International Colour Authority">International Colour Authority</a></li> <li><a href="/wiki/International_Commission_on_Illumination" title="International Commission on Illumination">International Commission on Illumination</a> (CIE)</li> <li><a href="/wiki/International_Color_Consortium" title="International Color Consortium">International Colour Consortium</a></li> <li><a href="/wiki/International_Colour_Association" title="International Colour Association">International Colour Association</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Names</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Lists_of_colors" title="Lists of colors">Lists</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_colours:_A%E2%80%93F" class="mw-redirect" title="List of colours: A–F">List of colours: A–F</a></li> <li><a href="/wiki/List_of_colours:_G%E2%80%93M" class="mw-redirect" title="List of colours: G–M">List of colours: G–M</a></li> <li><a href="/wiki/List_of_colours:_N%E2%80%93Z" class="mw-redirect" title="List of colours: N–Z">List of colours: N–Z</a></li> <li><a href="/wiki/List_of_colours_(compact)" class="mw-redirect" title="List of colours (compact)">List of colours (compact)</a></li> <li><a href="/wiki/List_of_colours_by_shade" class="mw-redirect" title="List of colours by shade">List of colours by shade</a></li> <li><a href="/wiki/List_of_colour_palettes" class="mw-redirect" title="List of colour palettes">List of colour palettes</a></li> <li><a href="/wiki/List_of_color_spaces_and_their_uses" title="List of color spaces and their uses">List of colour spaces</a></li> <li><a href="/wiki/List_of_Crayola_crayon_colours" class="mw-redirect" title="List of Crayola crayon colours">List of Crayola crayon colours</a> <ul><li><a href="/wiki/History_of_Crayola_crayons" title="History of Crayola crayons">history</a></li></ul></li> <li><a href="/wiki/Colour_chart" class="mw-redirect" title="Colour chart">Colour chart</a></li> <li><a href="/wiki/List_of_RAL_colours" title="List of RAL colours">List of RAL colours</a></li> <li><a href="/wiki/Web_colors" title="Web colors">List of web colours</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_colors_by_shade" title="List of colors by shade">Shades of:</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Shades_of_red" title="Shades of red">Red</a></li> <li><a href="/wiki/Shades_of_orange" title="Shades of orange">Orange</a></li> <li><a href="/wiki/Shades_of_yellow" title="Shades of yellow">Yellow</a></li> <li><a href="/wiki/Shades_of_green" title="Shades of green">Green</a></li> <li><a href="/wiki/Shades_of_cyan" title="Shades of cyan">Cyan</a></li> <li><a href="/wiki/Shades_of_blue" title="Shades of blue">Blue</a></li> <li><a href="/wiki/Shades_of_violet" title="Shades of violet">Violet</a></li> <li><a href="/wiki/Shades_of_purple" title="Shades of purple">Purple</a></li> <li><a href="/wiki/Shades_of_magenta" title="Shades of magenta">Magenta</a></li> <li><a href="/wiki/Shades_of_pink" title="Shades of pink">Pink</a></li> <li><a href="/wiki/Shades_of_brown" title="Shades of brown">Brown</a></li> <li><a href="/wiki/Shades_of_white" title="Shades of white">White</a></li> <li><a href="/wiki/Shades_of_gray" title="Shades of gray">Gray</a></li> <li><a href="/wiki/Shades_of_black" title="Shades of black">Black</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Index_of_color-related_articles" title="Index of color-related articles">Related</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Visual_perception" title="Visual perception">Vision</a> <ul><li><a href="/wiki/Contrast_(vision)" title="Contrast (vision)">Contrast</a></li></ul></li> <li><a href="/wiki/Qualia" title="Qualia">Qualia</a></li> <li><a href="/wiki/Lighting" 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