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id="content" class="mw-body"> <div class="banner-container"> <div id="siteNotice"></div> </div> <div class="pre-content heading-holder"> <div class="page-heading"> <h1 id="firstHeading" class="firstHeading mw-first-heading">Sigma</h1> <div class="tagline"></div> </div> <ul id="p-associated-pages" class="minerva__tab-container"> <li class="minerva__tab selected"> <a class="minerva__tab-text" href="/wiki/Sigma" rel="" data-event-name="tabs.subject">Article</a> </li> <li class="minerva__tab "> <a class="minerva__tab-text" href="/wiki/Talk:Sigma" rel="discussion" data-event-name="tabs.talk">Talk</a> </li> </ul> <nav class="page-actions-menu"> <ul id="p-views" class="page-actions-menu__list"> <li id="language-selector" class="page-actions-menu__list-item"> <a role="button" href="#p-lang" data-mw="interface" data-event-name="menu.languages" title="Language" class="cdx-button cdx-button--size-large cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--icon-only 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title="Medial sigma">Medial sigma</a>)</div> </div> <div id="bodyContent" class="content"> <div id="mw-content-text" class="mw-body-content"><script>function mfTempOpenSection(id){var block=document.getElementById("mf-section-"+id);block.className+=" open-block";block.previousSibling.className+=" open-block";}</script><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><section class="mf-section-0" id="mf-section-0"> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">This article is about uses of the Greek letter. For other uses, see <a href="/wiki/Sigma_(disambiguation)" class="mw-disambig" title="Sigma (disambiguation)">Sigma (disambiguation)</a>.</div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Not to be confused with <a href="/wiki/Stigma_(disambiguation)" class="mw-redirect mw-disambig" title="Stigma (disambiguation)">Stigma</a>.</div> <style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol 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#aaa;line-height:1.6em;font-weight:bold;padding-bottom:0.4em;border-bottom:1px solid #aaa}</style><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"> Sigma (<a href="/wiki/Help:IPA/English" title="Help:IPA/English">/ˈsɪɡmə/</a> <a href="/wiki/Help:Pronunciation_respelling_key" title="Help:Pronunciation respelling key">SIG-mə</a>;<a href="#cite_note-1">[1]</a> <a href="/wiki/Uppercase" class="mw-redirect" title="Uppercase">uppercase</a> Σ, <a href="/wiki/Lowercase" class="mw-redirect" title="Lowercase">lowercase</a> σ, lowercase in word-final position ς; <style data-mw-deduplicate="TemplateStyles:r1248666159">.mw-parser-output .tfd-dated{font-size:85%}.mw-parser-output .tfd-default{border-bottom:1px solid var(--border-color-base,#a2a9b1);clear:both;text-align:center}.mw-parser-output .tfd-tiny{font-weight:bold}.mw-parser-output .tfd-inline{border:1px solid var(--border-color-base,#a2a9b1)}.mw-parser-output .tfd-sidebar{border-bottom:1px solid var(--border-color-base,#a2a9b1);text-align:center;position:relative}@media(min-width:640px){.mw-parser-output .tfd-sidebar{clear:right;float:right;width:22em}}</style><a href="/wiki/Wikipedia:Templates_for_discussion/Log/2024_November_12#Template:Lang-grc-gre" title="Wikipedia:Templates for discussion/Log/2024 November 12">‹See Tfd›</a><a href="/wiki/Greek_language" title="Greek language">Greek</a>: σίγμα) is the eighteenth letter of the <a href="/wiki/Greek_alphabet" title="Greek alphabet">Greek alphabet</a>. In the system of <a href="/wiki/Greek_numerals" title="Greek numerals">Greek numerals</a>, it has a value of 200. In general mathematics, uppercase Σ is used as an <a href="/wiki/Operator_(mathematics)" title="Operator (mathematics)">operator</a> for <a href="/wiki/Summation" title="Summation">summation</a>. When used at the end of a <a href="/wiki/Letter_case" title="Letter case">letter-case</a> word (one that does not use <a href="/wiki/All_caps" title="All caps">all caps</a>), the <a href="/wiki/Final_form" title="Final form">final form</a> (ς) is used. In Ὀδυσσεύς (Odysseus), for example, the two lowercase sigmas (σ) in the center of the name are distinct from the word-final sigma (ς) at the end. The <a href="/wiki/Latin_alphabet" title="Latin alphabet">Latin</a> letter <a href="/wiki/S" title="S">S</a> derives from sigma while the <a href="/wiki/Cyrillic_script" title="Cyrillic script">Cyrillic</a> letter <a href="/wiki/Es_(Cyrillic)" title="Es (Cyrillic)">Es</a> derives from a <a href="#Lunate_sigma">lunate form</a> of this letter. <div id="toc" class="toc" role="navigation" aria-labelledby="mw-toc-heading"><input type="checkbox" role="button" id="toctogglecheckbox" class="toctogglecheckbox" style="display:none"><div class="toctitle" lang="en" dir="ltr"><h2 id="mw-toc-heading">Contents</h2><label class="toctogglelabel" for="toctogglecheckbox"></label></div> <ul> <li class="toclevel-1 tocsection-1"><a href="#History">1 History</a> <ul> <li class="toclevel-2 tocsection-2"><a href="#Lunate_sigma">1.1 Lunate sigma</a></li> <li class="toclevel-2 tocsection-3"><a href="#Derived_alphabets">1.2 Derived alphabets</a></li> </ul> </li> <li class="toclevel-1 tocsection-4"><a href="#Uses">2 Uses</a> <ul> <li class="toclevel-2 tocsection-5"><a href="#Language_and_linguistics">2.1 Language and linguistics</a></li> <li class="toclevel-2 tocsection-6"><a href="#Science_and_mathematics">2.2 Science and mathematics</a> <ul> <li class="toclevel-3 tocsection-7"><a href="#Mathematics">2.2.1 Mathematics</a></li> <li class="toclevel-3 tocsection-8"><a href="#Biology,_physiology,_and_medicine">2.2.2 Biology, physiology, and medicine</a></li> <li class="toclevel-3 tocsection-9"><a href="#Business,_finance,_and_economics">2.2.3 Business, finance, and economics</a></li> <li class="toclevel-3 tocsection-10"><a href="#Chemistry">2.2.4 Chemistry</a></li> <li class="toclevel-3 tocsection-11"><a href="#Engineering_and_computer_science">2.2.5 Engineering and computer science</a></li> <li class="toclevel-3 tocsection-12"><a href="#Physics">2.2.6 Physics</a></li> </ul> </li> <li class="toclevel-2 tocsection-13"><a href="#Organizations">2.3 Organizations</a></li> </ul> </li> <li class="toclevel-1 tocsection-14"><a href="#Unicode">3 Unicode</a></li> <li class="toclevel-1 tocsection-15"><a href="#See_also">4 See also</a></li> <li class="toclevel-1 tocsection-16"><a href="#References">5 References</a> <ul> <li class="toclevel-2 tocsection-17"><a href="#Notes">5.1 Notes</a></li> <li class="toclevel-2 tocsection-18"><a href="#Citations">5.2 Citations</a></li> </ul> </li> </ul> </div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(1)"><h2 id="History">History</h2></div><section class="mf-section-1 collapsible-block" id="mf-section-1"> The shape (Σς) and alphabetic position of sigma is derived from the <a href="/wiki/Phoenician_alphabet" title="Phoenician alphabet">Phoenician</a> letter <a href="/wiki/File:Phoenician_sin.svg" class="mw-file-description" title="𐤔"><noscript><img alt="𐤔" src="//upload.wikimedia.org/wikipedia/commons/thumb/7/76/Phoenician_sin.svg/15px-Phoenician_sin.svg.png" decoding="async" width="15" height="15" class="mw-file-element" data-file-width="85" data-file-height="85"></noscript><span class="lazy-image-placeholder" style="width: 15px;height: 15px;" data-src="//upload.wikimedia.org/wikipedia/commons/thumb/7/76/Phoenician_sin.svg/15px-Phoenician_sin.svg.png" data-alt="𐤔" data-width="15" data-height="15" data-srcset="//upload.wikimedia.org/wikipedia/commons/thumb/7/76/Phoenician_sin.svg/23px-Phoenician_sin.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/7/76/Phoenician_sin.svg/30px-Phoenician_sin.svg.png 2x" data-class="mw-file-element"> </a> (<a href="/wiki/Shin_(letter)" title="Shin (letter)">shin</a>). Sigma's original name may have been san, but due to the complicated early history of the Greek <a href="/wiki/Archaic_Greek_alphabets" title="Archaic Greek alphabets">epichoric alphabets</a>, san came to be identified as a separate letter in the Greek alphabet, represented as <a href="/wiki/San_(letter)" title="San (letter)">Ϻ</a>.<a href="#cite_note-woodard-2">[2]</a> <a href="/wiki/Herodotus" title="Herodotus">Herodotus</a> reports that "san" was the name given by the <a href="/wiki/Doric_Greek" title="Doric Greek">Dorians</a> to the same letter called "sigma" by the <a href="/wiki/Ionic_Greek" title="Ionic Greek">Ionians</a>.<a href="#cite_note-3">[i]</a><a href="#cite_note-4">[3]</a> According to one hypothesis,<a href="#cite_note-jeffery25-5">[4]</a> the name "sigma" may continue that of Phoenician <a href="/wiki/Samekh" title="Samekh">samekh</a> (<a href="/wiki/File:Phoenician_samekh.svg" class="mw-file-description" title="𐤎"><noscript><img alt="𐤎" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Phoenician_samekh.svg/15px-Phoenician_samekh.svg.png" decoding="async" width="15" height="15" class="mw-file-element" data-file-width="85" data-file-height="85"></noscript><span class="lazy-image-placeholder" style="width: 15px;height: 15px;" data-src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Phoenician_samekh.svg/15px-Phoenician_samekh.svg.png" data-alt="𐤎" data-width="15" data-height="15" data-srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Phoenician_samekh.svg/23px-Phoenician_samekh.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Phoenician_samekh.svg/30px-Phoenician_samekh.svg.png 2x" data-class="mw-file-element"> </a>), the letter continued through Greek xi, represented as <a href="/wiki/Xi_(letter)" title="Xi (letter)">Ξ</a>. Alternatively, the name may have been a Greek innovation that simply meant 'hissing', from the root of σίζω (sízō, from <a href="/wiki/Proto-Greek_language" title="Proto-Greek language">Proto-Greek</a> *sig-jō 'I hiss').<a href="#cite_note-woodard-2">[2]</a> <div class="mw-heading mw-heading3"><h3 id="Lunate_sigma">Lunate sigma</h3></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Madaba_Jerusalem_Mosaic.jpg" class="mw-file-description"><noscript><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3d/Madaba_Jerusalem_Mosaic.jpg/220px-Madaba_Jerusalem_Mosaic.jpg" decoding="async" width="220" height="147" class="mw-file-element" data-file-width="1800" data-file-height="1200"></noscript><span class="lazy-image-placeholder" style="width: 220px;height: 147px;" data-src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3d/Madaba_Jerusalem_Mosaic.jpg/220px-Madaba_Jerusalem_Mosaic.jpg" data-width="220" data-height="147" data-srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3d/Madaba_Jerusalem_Mosaic.jpg/330px-Madaba_Jerusalem_Mosaic.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3d/Madaba_Jerusalem_Mosaic.jpg/440px-Madaba_Jerusalem_Mosaic.jpg 2x" data-class="mw-file-element"> </a><figcaption>The <a href="/wiki/Madaba_Map" title="Madaba Map">Madaba Map</a>, a sixth-century mosaic of <a href="/wiki/Jerusalem" title="Jerusalem">Jerusalem</a> (Η <a href="/wiki/Agia_(disambiguation)" class="mw-redirect mw-disambig" title="Agia (disambiguation)">ΑΓΙΑ</a> <a href="/wiki/Polis" title="Polis">ΠΟΛΙϹ</a>) uses the lunate sigma</figcaption></figure> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:Metochion_Gethsimanis,_Jerusalem.jpg" class="mw-file-description"><noscript><img src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Metochion_Gethsimanis%2C_Jerusalem.jpg/170px-Metochion_Gethsimanis%2C_Jerusalem.jpg" decoding="async" width="170" height="529" class="mw-file-element" data-file-width="666" data-file-height="2072"></noscript><span class="lazy-image-placeholder" style="width: 170px;height: 529px;" data-src="//upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Metochion_Gethsimanis%2C_Jerusalem.jpg/170px-Metochion_Gethsimanis%2C_Jerusalem.jpg" data-width="170" data-height="529" data-srcset="//upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Metochion_Gethsimanis%2C_Jerusalem.jpg/255px-Metochion_Gethsimanis%2C_Jerusalem.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/1/1f/Metochion_Gethsimanis%2C_Jerusalem.jpg/340px-Metochion_Gethsimanis%2C_Jerusalem.jpg 2x" data-class="mw-file-element"> </a><figcaption>A plaque reading "<a href="/wiki/Metochion" title="Metochion">Metochion</a> of <a href="/wiki/Gethsemane" title="Gethsemane">Gethsemane</a>" (Μετόχιον Γεθσημανῆς) in Jerusalem, with a lunate sigma both at the end and in the middle of the word</figcaption></figure> In handwritten Greek during the <a href="/wiki/Hellenistic_period" title="Hellenistic period">Hellenistic period</a> (4th–3rd century BC), the <a href="/wiki/Epigraphic" class="mw-redirect" title="Epigraphic">epigraphic</a> form of Σ was simplified into a C-like shape,<a href="#cite_note-6">[5]</a> which has also been found on coins from the 4th century BC onward.<a href="#cite_note-7">[6]</a> This became the universal standard form of sigma during late antiquity and the Middle Ages. Today, it is known as lunate sigma (uppercase Ϲ, lowercase ϲ), because of its <a href="/wiki/Crescent" title="Crescent">crescent</a>-like shape, and is still widely used in decorative typefaces in Greece, especially in religious and church contexts, as well as in some modern print editions of classical Greek texts. A dotted lunate sigma (sigma periestigmenon, Ͼ) was used by <a href="/wiki/Aristarchus_of_Samothrace" title="Aristarchus of Samothrace">Aristarchus of Samothrace</a> (220–143 BC) as an editorial sign indicating that the line marked as such is at an incorrect position. Similarly, a reversed sigma (<a href="/wiki/Antisigma" class="mw-redirect" title="Antisigma">antisigma</a>, Ͻ), may mark a line that is out of place. A dotted antisigma (antisigma periestigmenon, Ͽ) may indicate a line after which rearrangements should be made, or to variant readings of uncertain priority. In Greek inscriptions from the late first century BC onwards, Ͻ was an abbreviation indicating that a man's father's name is the same as his own name, thus Dionysodoros son of Dionysodoros would be written Διονυσόδωρος Ͻ (Dionysodoros Dionysodorou).<a href="#cite_note-8">[7]</a><a href="#cite_note-9">[8]</a> In <a href="/wiki/Unicode" title="Unicode">Unicode</a>, the above variations of lunate sigma are encoded as <style data-mw-deduplicate="TemplateStyles:r886049734">.mw-parser-output .monospaced{font-family:monospace,monospace}</style>U+03F9 Ϲ GREEK CAPITAL LUNATE SIGMA SYMBOL; <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03FD Ͻ GREEK CAPITAL REVERSED LUNATE SIGMA SYMBOL, <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03FE Ͼ GREEK CAPITAL DOTTED LUNATE SIGMA SYMBOL, and <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03FF Ͽ GREEK CAPITAL REVERSED DOTTED LUNATE SIGMA SYMBOL. <div class="mw-heading mw-heading3"><h3 id="Derived_alphabets">Derived alphabets</h3></div> Sigma was adopted in the <a href="/wiki/Old_Italic_alphabets" class="mw-redirect" title="Old Italic alphabets">Old Italic alphabets</a> beginning in the 8th century BC. At that time a simplified three-stroke version, omitting the lowermost stroke, was already found in Western Greek alphabets, and was incorporated into classical <a href="/wiki/Etruscan_alphabet" title="Etruscan alphabet">Etruscan</a> and <a href="/wiki/Old_Italic_scripts" title="Old Italic scripts">Oscan</a>, as well as in the earliest <a href="/wiki/History_of_the_Latin_script" title="History of the Latin script">Latin</a> <a href="/wiki/Epigraphy" title="Epigraphy">epigraphy</a> (early Latin <a href="/wiki/S" title="S">S</a>), such as the <a href="/wiki/Duenos_inscription" title="Duenos inscription">Duenos inscription</a>. The alternation between three and four (and occasionally more than four) strokes was also adopted into the <a href="/wiki/Elder_Futhark" title="Elder Futhark">early runic alphabet</a> (early form of the <a href="/wiki/Sowil%C5%8D" class="mw-redirect" title="Sowilō">s-rune</a>). Both the <a href="/wiki/Anglo-Saxon_runes" title="Anglo-Saxon runes">Anglo-Saxon runes</a> and the <a href="/wiki/Younger_Futhark" title="Younger Futhark">Younger Futhark</a> consistently use the simplified three-stroke version. The letter <a href="/wiki/Es_(Cyrillic)" title="Es (Cyrillic)">С</a> of <a href="/wiki/Cyrillic_script" title="Cyrillic script">Cyrillic script</a> originates in the <a href="#Lunate_sigma">lunate form</a> of Sigma. </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(2)"><h2 id="Uses">Uses</h2></div><section class="mf-section-2 collapsible-block" id="mf-section-2"> <div class="mw-heading mw-heading3"><h3 id="Language_and_linguistics">Language and linguistics</h3></div> <ul><li>In both <a href="/wiki/Ancient_Greek" title="Ancient Greek">Ancient</a> and <a href="/wiki/Modern_Greek" title="Modern Greek">Modern Greek</a>, the sigma represents the <a href="/wiki/Voiceless_alveolar_fricative" title="Voiceless alveolar fricative">voiceless alveolar fricative</a> <a href="/wiki/Help:IPA/Greek" title="Help:IPA/Greek">[s]</a>. In Modern Greek, this sound is <a href="/wiki/Voice_(phonetics)" title="Voice (phonetics)">voiced</a> to the <a href="/wiki/Voiced_alveolar_fricative" title="Voiced alveolar fricative">voiced alveolar fricative</a> <a href="/wiki/Help:IPA/Greek" title="Help:IPA/Greek">[z]</a> when occurring before <a href="/wiki/Help:IPA/Greek" title="Help:IPA/Greek">[m]</a>, <a href="/wiki/Help:IPA/Greek" title="Help:IPA/Greek">[n]</a>, <a href="/wiki/Help:IPA/Greek" title="Help:IPA/Greek">[v]</a>, <a href="/wiki/Help:IPA/Greek" title="Help:IPA/Greek">[ð]</a> or <a href="/wiki/Help:IPA/Greek" title="Help:IPA/Greek">[ɣ]</a>.</li> <li>The uppercase form of sigma (Σ) was re-borrowed into the <a href="/wiki/Latin_alphabet" title="Latin alphabet">Latin alphabet</a>—more precisely, the <a href="/wiki/Africa_Alphabet" title="Africa Alphabet">International African Alphabet</a>—to serve as the uppercase of modern <a href="/wiki/Esh_(letter)" title="Esh (letter)">esh</a> (lowercase: ʃ).</li> <li>In <a href="/wiki/Phonology" title="Phonology">phonology</a>, σ is used to represent <a href="/wiki/Syllable" title="Syllable">syllables</a>.</li> <li>In <a href="/wiki/Linguistics" title="Linguistics">linguistics</a>, Σ represents the set of symbols that form an alphabet (see also <a href="/wiki/Computer_Science" class="mw-redirect" title="Computer Science">computer science</a>).</li> <li>In <a href="/wiki/Historical_linguistics" title="Historical linguistics">historical linguistics</a>, Σ is used to represent a <a href="/wiki/Common_Brittonic" title="Common Brittonic">Common Brittonic</a> consonant with a sound between [<a href="/wiki/Voiceless_alveolar_fricative" title="Voiceless alveolar fricative">s</a>] and [<a href="/wiki/Voiceless_glottal_fricative" title="Voiceless glottal fricative">h</a>]; perhaps an <a href="/wiki/Aspirated_consonant" title="Aspirated consonant">aspirated</a> <a href="/wiki/Voiceless_postalveolar_fricative" title="Voiceless postalveolar fricative">[ʃʰ]</a>.<a href="#cite_note-10">[9]</a></li></ul> <div class="mw-heading mw-heading3"><h3 id="Science_and_mathematics">Science and mathematics</h3></div> <div class="mw-heading mw-heading4"><h4 id="Mathematics">Mathematics</h4></div> <ul><li>In general mathematics, lowercase σ is commonly used to represent unknown angles, additionally serving as a shorthand for "<a href="/wiki/Countable_set" title="Countable set">countably</a>", whereas Σ is regularly used as the <a href="/wiki/Operator_(mathematics)" title="Operator (mathematics)">operator</a> for <a href="/wiki/Summation" title="Summation">summation</a>, e.g.:</li></ul> <math display="block" xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \sum _{k=0}^{5}k=0+1+2+3+4+5=15}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <munderover> <mo>∑</mo> <mrow class="MJX-TeXAtom-ORD"> <mi>k</mi> <mo>=</mo> <mn>0</mn> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>5</mn> </mrow> </munderover> <mi>k</mi> <mo>=</mo> <mn>0</mn> <mo>+</mo> <mn>1</mn> <mo>+</mo> <mn>2</mn> <mo>+</mo> <mn>3</mn> <mo>+</mo> <mn>4</mn> <mo>+</mo> <mn>5</mn> <mo>=</mo> <mn>15</mn> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \sum _{k=0}^{5}k=0+1+2+3+4+5=15}</annotation> </semantics> </math><noscript><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c97f24d32e3a9198cefed79e510a8f086a88263f" class="mwe-math-fallback-image-display mw-invert skin-invert" aria-hidden="true" style="vertical-align: -3.171ex; width:34.652ex; height:7.509ex;" alt="{\displaystyle \sum _{k=0}^{5}k=0+1+2+3+4+5=15}"></noscript><span class="lazy-image-placeholder" style="width: 34.652ex;height: 7.509ex;vertical-align: -3.171ex;" data-src="https://wikimedia.org/api/rest_v1/media/math/render/svg/c97f24d32e3a9198cefed79e510a8f086a88263f" data-alt="{\displaystyle \sum _{k=0}^{5}k=0+1+2+3+4+5=15}" data-class="mwe-math-fallback-image-display mw-invert skin-invert">  <ul><li>In <a href="/wiki/Mathematical_logic" title="Mathematical logic">mathematical logic</a>, <math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \Sigma _{n}^{0}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msubsup> <mi mathvariant="normal">Σ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>n</mi> </mrow> <mrow class="MJX-TeXAtom-ORD"> <mn>0</mn> </mrow> </msubsup> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \Sigma _{n}^{0}}</annotation> </semantics> </math><noscript><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/7a4ef07c43c84a667249d8d7400a79d53b0c1577" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.671ex; width:2.897ex; height:2.843ex;" alt="{\displaystyle \Sigma _{n}^{0}}"></noscript><span class="lazy-image-placeholder" style="width: 2.897ex;height: 2.843ex;vertical-align: -0.671ex;" data-src="https://wikimedia.org/api/rest_v1/media/math/render/svg/7a4ef07c43c84a667249d8d7400a79d53b0c1577" data-alt="{\displaystyle \Sigma _{n}^{0}}" data-class="mwe-math-fallback-image-inline mw-invert skin-invert">  is used to denote the set of formulae with bounded quantifiers beginning with existential quantifiers, alternating <math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle n-1}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>n</mi> <mo>−</mo> <mn>1</mn> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle n-1}</annotation> </semantics> </math><noscript><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/fbd0b0f32b28f51962943ee9ede4fb34198a2521" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.505ex; width:5.398ex; height:2.343ex;" alt="{\displaystyle n-1}"></noscript><span class="lazy-image-placeholder" style="width: 5.398ex;height: 2.343ex;vertical-align: -0.505ex;" data-src="https://wikimedia.org/api/rest_v1/media/math/render/svg/fbd0b0f32b28f51962943ee9ede4fb34198a2521" data-alt="{\displaystyle n-1}" data-class="mwe-math-fallback-image-inline mw-invert skin-invert">  times between existential and universal quantifiers. This notation reflects an indirect analogy between the relationship of summation and products on one hand, and existential and universal quantifiers on the other. See the article on the <a href="/wiki/Arithmetic_hierarchy" class="mw-redirect" title="Arithmetic hierarchy">arithmetic hierarchy</a>.</li> <li>In <a href="/wiki/Statistics" title="Statistics">statistics</a>, σ represents the <a href="/wiki/Standard_deviation" title="Standard deviation">standard deviation</a> of population or <a href="/wiki/Probability_distribution" title="Probability distribution">probability distribution</a> (where <a href="/wiki/Mu_(letter)" title="Mu (letter)">mu</a> or μ is used for the mean).</li> <li>In <a href="/wiki/Topology" title="Topology">topology</a>, σ-compact <a href="/wiki/Topological_space" title="Topological space">topological space</a> is one that can be written as a countable <a href="/wiki/Union_(set_theory)" title="Union (set theory)">union</a> of <a href="/wiki/Compact_space" title="Compact space">compact subsets</a>.</li> <li>In <a href="/wiki/Mathematical_analysis" title="Mathematical analysis">mathematical analysis</a> and in <a href="/wiki/Probability_theory" title="Probability theory">probability theory</a>, there is a type of <a href="/wiki/Field_of_sets" title="Field of sets">algebra of sets</a> known as <a href="/wiki/Sigma-algebra" class="mw-redirect" title="Sigma-algebra">σ-algebra</a> (aka σ-field). Sigma algebra also includes terms such as: <ul><li>σ(A), denoting the <a href="/wiki/%CE%A3-algebra#%CF%83-algebras_generated_by_families_of_sets" title="Σ-algebra">generated sigma-algebra</a> of a set A</li> <li><a href="/wiki/%CE%A3-finite_measure" title="Σ-finite measure">Σ-finite measure</a> (see <a href="/wiki/Measure_(mathematics)" title="Measure (mathematics)">measure theory</a>)</li></ul></li> <li>In <a href="/wiki/Number_theory" title="Number theory">number theory</a>, σ is included in various <a href="/wiki/Divisor_function" title="Divisor function">divisor functions</a>, especially the sigma function or sum-of-divisors function.</li> <li>In <a href="/wiki/Applied_mathematics" title="Applied mathematics">applied mathematics</a>, σ(T) denotes the spectrum of a <a href="/wiki/Linear_map" title="Linear map">linear map</a> T.</li> <li>In <a href="/wiki/Complex_analysis" title="Complex analysis">complex analysis</a>, σ is used in the <a href="/wiki/Weierstrass_functions#Weierstrass_sigma-function" title="Weierstrass functions">Weierstrass sigma-function</a>.</li> <li>In <a href="/wiki/Probability_theory" title="Probability theory">probability theory</a> and <a href="/wiki/Statistics" title="Statistics">statistics</a>, Σ denotes the <a href="/wiki/Covariance_matrix" title="Covariance matrix">covariance matrix</a> of a set of <a href="/wiki/Random_variable" title="Random variable">random variables</a>, sometimes in the form <math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \;|\!\!\!\Sigma }"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mspace width="thickmathspace"></mspace> <mrow class="MJX-TeXAtom-ORD"> <mo stretchy="false">|</mo> </mrow> <mspace width="negativethinmathspace"></mspace> <mspace width="negativethinmathspace"></mspace> <mspace width="negativethinmathspace"></mspace> <mi mathvariant="normal">Σ</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \;|\!\!\!\Sigma }</annotation> </semantics> </math><noscript><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/e6b2e3a8f508bcd0934748188dae32ab92b565d5" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:1.809ex; height:2.843ex;" alt="{\displaystyle \;|\!\!\!\Sigma }"></noscript><span class="lazy-image-placeholder" style="width: 1.809ex;height: 2.843ex;vertical-align: -0.838ex;" data-src="https://wikimedia.org/api/rest_v1/media/math/render/svg/e6b2e3a8f508bcd0934748188dae32ab92b565d5" data-alt="{\displaystyle \;|\!\!\!\Sigma }" data-class="mwe-math-fallback-image-inline mw-invert skin-invert">  to distinguish it from the summation operator.</li> <li><a href="/wiki/Spectral_theory" title="Spectral theory">Theoretical spectral analysis</a> uses σ as standard deviation opposed to lowercase <a href="/wiki/Mu_(letter)" title="Mu (letter)">mu</a> as the absolute mean value.</li></ul> <div class="mw-heading mw-heading4"><h4 id="Biology,_physiology,_and_medicine">Biology, physiology, and medicine</h4></div> <ul><li>In <a href="/wiki/Biology" title="Biology">biology</a>, the <a href="/wiki/Sigma_receptor" title="Sigma receptor">sigma receptor</a> (σ–receptors) is a type of <a href="/wiki/Cell_surface_receptor" title="Cell surface receptor">cell surface receptor</a>.</li> <li>In <a href="/wiki/Biochemistry" title="Biochemistry">biochemistry</a>, the <a href="/wiki/Sigma_factor" title="Sigma factor">σ factor</a> (or specificity factor) is a protein found in <a href="/wiki/RNA_polymerase" title="RNA polymerase">RNA polymerase</a>.</li> <li>In <a href="/wiki/Bone" title="Bone">bone physiology</a>, the <a href="/wiki/Bone_remodeling_period" title="Bone remodeling period">bone remodeling period</a>—i.e., the <a href="/wiki/Sigma_(bone_remodeling)" class="mw-redirect" title="Sigma (bone remodeling)">life span</a> of a basic multicellular unit—has historically been referred to as the sigma period</li> <li>In early 20th-century <a href="/wiki/Physiology" title="Physiology">physiology</a> literature, σ had been used to represent <a href="/wiki/Millisecond" title="Millisecond">milliseconds</a><a href="#cite_note-Hill1935-11">[10]</a></li></ul> <div class="mw-heading mw-heading4"><h4 id="Business,_finance,_and_economics">Business, finance, and economics</h4></div> <ul><li>In <a href="/wiki/Finance" title="Finance">finance</a>, σ is the symbol used to represent <a href="/wiki/Volatility_(finance)" title="Volatility (finance)">volatility</a> of <a href="/wiki/Stock" title="Stock">stocks</a>, usually measured by the <a href="/wiki/Standard_deviation" title="Standard deviation">standard deviation</a> of <a href="/wiki/Logarithmic_return" class="mw-redirect" title="Logarithmic return">logarithmic returns</a>.</li> <li>In <a href="/wiki/Accounting" title="Accounting">accounting</a>, Σ indicates the <a href="/wiki/Balance_(accounting)" title="Balance (accounting)">balance</a> of invoice classes and the overall amount of debts and demands.</li> <li>In <a href="/wiki/Macroeconomics" title="Macroeconomics">macroeconomics</a>, σ is used in equations to represent the <a href="/wiki/Elasticity_of_substitution" title="Elasticity of substitution">elasticity of substitution</a> between two inputs.</li> <li>In the <a href="/wiki/Machine_industry" title="Machine industry">machine industry</a>, <a href="/wiki/Six_Sigma" title="Six Sigma">Six Sigma</a> (6σ) is a quality model based on the <a href="/wiki/Standard_deviation" title="Standard deviation">standard deviation</a>.</li></ul> <div class="mw-heading mw-heading4"><h4 id="Chemistry">Chemistry</h4></div> <ul><li><a href="/wiki/Sigma_bond" title="Sigma bond">Sigma bonds</a> (σ bonds) are the strongest type of <a href="/wiki/Covalent" class="mw-redirect" title="Covalent">covalent</a> <a href="/wiki/Chemical_bond" title="Chemical bond">chemical bond</a>.</li> <li>In <a href="/wiki/Organic_chemistry" title="Organic chemistry">organic chemistry</a>, σ symbolizes the sigma constant of <a href="/wiki/Hammett_equation" title="Hammett equation">Hammett equation</a>.</li> <li>In <a href="/wiki/Alchemy" title="Alchemy">alchemy</a>, Σ was sometimes used to represent <a href="/wiki/Sugar" title="Sugar">sugar</a>.</li></ul> <div class="mw-heading mw-heading4"><h4 id="Engineering_and_computer_science">Engineering and computer science</h4></div> <ul><li>In <a href="/wiki/Computer_Science" class="mw-redirect" title="Computer Science">computer science</a>, Σ represents the set of symbols that form an alphabet (see also <a href="/wiki/Linguistics" title="Linguistics">linguistics</a>)</li> <li><a href="/wiki/Relational_algebra" title="Relational algebra">Relational algebra</a> uses the values <math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \sigma _{a\theta b}(R)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>σ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>θ</mi> <mi>b</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>R</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \sigma _{a\theta b}(R)}</annotation> </semantics> </math><noscript><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3bebf61399c9377559b25a761ba97b69e94834db" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:7.479ex; height:2.843ex;" alt="{\displaystyle \sigma _{a\theta b}(R)}"></noscript><span class="lazy-image-placeholder" style="width: 7.479ex;height: 2.843ex;vertical-align: -0.838ex;" data-src="https://wikimedia.org/api/rest_v1/media/math/render/svg/3bebf61399c9377559b25a761ba97b69e94834db" data-alt="{\displaystyle \sigma _{a\theta b}(R)}" data-class="mwe-math-fallback-image-inline mw-invert skin-invert">  and <math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle \sigma _{a\theta v}(R)}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <msub> <mi>σ</mi> <mrow class="MJX-TeXAtom-ORD"> <mi>a</mi> <mi>θ</mi> <mi>v</mi> </mrow> </msub> <mo stretchy="false">(</mo> <mi>R</mi> <mo stretchy="false">)</mo> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle \sigma _{a\theta v}(R)}</annotation> </semantics> </math><noscript><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/05b4fda9680d7a5d8efcd9d2f026729430c10926" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:7.571ex; height:2.843ex;" alt="{\displaystyle \sigma _{a\theta v}(R)}"></noscript><span class="lazy-image-placeholder" style="width: 7.571ex;height: 2.843ex;vertical-align: -0.838ex;" data-src="https://wikimedia.org/api/rest_v1/media/math/render/svg/05b4fda9680d7a5d8efcd9d2f026729430c10926" data-alt="{\displaystyle \sigma _{a\theta v}(R)}" data-class="mwe-math-fallback-image-inline mw-invert skin-invert">  to denote <a href="/wiki/Selection_(relational_algebra)" title="Selection (relational algebra)">selections</a>, which are a type of <a href="/wiki/Unary_operation" title="Unary operation">unary operation</a>.</li> <li>In <a href="/wiki/Machine_learning" title="Machine learning">machine learning</a>, σ is used in the formula that derives the <a href="/wiki/Sigmoid_function" title="Sigmoid function">Sigmoid function</a>.</li> <li>In <a href="/wiki/Radar_jamming" class="mw-redirect" title="Radar jamming">radar jamming</a> or <a href="/wiki/Electronic_warfare" title="Electronic warfare">electronic warfare</a>, <a href="/wiki/Radar_cross-section" class="mw-redirect" title="Radar cross-section">radar cross-sections</a> (RCS) are commonly represented as σ when measuring the size of a target's image on radar.</li> <li>In <a href="/wiki/Signal_processing" title="Signal processing">signal processing</a>, σ denotes the <a href="/wiki/Damping_ratio" class="mw-redirect" title="Damping ratio">damping ratio</a> of a system parameter.</li> <li>In <a href="/wiki/Theoretical_computer_science" title="Theoretical computer science">theoretical computer science</a>, Σ serves as the <a href="/wiki/Busy_beaver" title="Busy beaver">busy beaver</a> function.</li> <li>In <a href="/wiki/Civil_engineering" title="Civil engineering">civil engineering</a>, σ refers to the normal stress applied on a material or structure.</li></ul> <div class="mw-heading mw-heading4"><h4 id="Physics">Physics</h4></div> <ul><li>In <a href="/wiki/Nuclear_physics" title="Nuclear physics">nuclear</a> and <a href="/wiki/Particle_physics" title="Particle physics">particle physics</a>, σ is used to denote <a href="/wiki/Cross_section_(physics)" title="Cross section (physics)">cross sections</a> in general (see also <a href="/wiki/Radar_cross-section" class="mw-redirect" title="Radar cross-section">RCS</a>), while Σ represents macroscopic <a href="/wiki/Cross_section_(physics)" title="Cross section (physics)">cross sections</a> [1/length].</li> <li>The symbol is to denote the <a href="/wiki/Stefan%E2%80%93Boltzmann_constant" class="mw-redirect" title="Stefan–Boltzmann constant">Stefan–Boltzmann constant</a>.</li> <li>In relation to fundamental properties of material, σ is often used to signify <a href="/wiki/Electrical_conductivity" class="mw-redirect" title="Electrical conductivity">electrical conductivity</a>.</li> <li>In <a href="/wiki/Electrostatics" title="Electrostatics">electrostatics</a>, σ represents <a href="/wiki/Surface_charge" title="Surface charge">surface charge</a> density.</li> <li>In <a href="/wiki/Continuum_mechanics" title="Continuum mechanics">continuum mechanics</a>, σ is used to signify <a href="/wiki/Stress_(physics)" class="mw-redirect" title="Stress (physics)">stress</a>.</li> <li>In <a href="/wiki/Condensed_matter_physics" title="Condensed matter physics">condensed matter physics</a>, Σ denotes <a href="/wiki/Self-energy" title="Self-energy">self-energy</a>.</li> <li>The symbol can be used to signify <a href="/wiki/Surface_tension" title="Surface tension">surface tension</a> (alternatively, <a href="/wiki/Gamma" title="Gamma">γ</a> or <a href="/wiki/T" title="T">T</a> are also used instead).</li> <li>In <a href="/wiki/Quantum_mechanics" title="Quantum mechanics">quantum mechanics</a>, σ is used to indicate <a href="/wiki/Pauli_matrices" title="Pauli matrices">Pauli matrices</a>.</li> <li>In <a href="/wiki/Astronomy" title="Astronomy">astronomy</a>, σ represents <a href="/wiki/Velocity_dispersion" title="Velocity dispersion">velocity dispersion</a>.</li> <li>In astronomy, the prefix Σ is used to designate double stars of the <a href="/w/index.php?title=Catalogus_Novus_Stellarum_Duplicium&action=edit&redlink=1" class="new" title="Catalogus Novus Stellarum Duplicium (page does not exist)">Catalogus Novus Stellarum Duplicium</a> by <a href="/wiki/Friedrich_Georg_Wilhelm_von_Struve" title="Friedrich Georg Wilhelm von Struve">Friedrich Georg Wilhelm von Struve</a>.</li> <li>In particle physics, Σ represents a class of <a href="/wiki/Baryon" title="Baryon">baryons</a>.</li></ul> <div class="mw-heading mw-heading3"><h3 id="Organizations">Organizations</h3></div> <ul><li>During the 1930s, an uppercase Σ was in use as the symbol of the <a href="/wiki/Brazilian_Integralism" title="Brazilian Integralism">Ação Integralista Brasileira</a>, a fascist political party in <a href="/wiki/Brazil" title="Brazil">Brazil</a>.</li> <li><a href="/wiki/Sigma_Corporation" title="Sigma Corporation">Sigma Corporation</a> uses the name of the letter but not the letter itself, but in many Internet forums, photographers refer to the company or its lenses using the letter.</li> <li><a href="/wiki/Sigma_Aldrich" class="mw-redirect" title="Sigma Aldrich">Sigma Aldrich</a> incorporate both the name and the character in their logo.</li></ul> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(3)"><h2 id="Unicode">Unicode</h2></div><section class="mf-section-3 collapsible-block" id="mf-section-3"> <ul><li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+037B ͻ GREEK SMALL REVERSED LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+037C ͼ GREEK SMALL DOTTED LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+037D ͽ GREEK SMALL REVERSED DOTTED LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03A3 Σ GREEK CAPITAL LETTER SIGMA (<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">&Sigma;)</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03C2 ς GREEK SMALL LETTER FINAL SIGMA (<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">&sigmaf;, &sigmav;, &varsigma;)</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03C3 σ GREEK SMALL LETTER SIGMA (<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">&sigma;)</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03F2 ϲ GREEK LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03F9 Ϲ GREEK CAPITAL LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03FD Ͻ GREEK CAPITAL REVERSED LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03FE Ͼ GREEK CAPITAL DOTTED LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+03FF Ͽ GREEK CAPITAL REVERSED DOTTED LUNATE SIGMA SYMBOL</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+2140 ⅀ DOUBLE-STRUCK N-ARY SUMMATION</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+2211 ∑ N-ARY SUMMATION (<link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">&Sum;, &sum;)</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+23B2 ⎲ SUMMATION TOP<a href="#cite_note-12">[a]</a></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+23B3 ⎳ SUMMATION BOTTOM</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+2CA4 Ⲥ COPTIC CAPITAL LETTER SIMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+2CA5 ⲥ COPTIC SMALL LETTER SIMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+2CEA ⳪ COPTIC SYMBOL SHIMA SIMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D6BA 𝚺 MATHEMATICAL BOLD CAPITAL SIGMA<a href="#cite_note-13">[b]</a></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D6D3 𝛓 MATHEMATICAL BOLD SMALL FINAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D6D4 𝛔 MATHEMATICAL BOLD SMALL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D6F4 𝛴 MATHEMATICAL ITALIC CAPITAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D70D 𝜍 MATHEMATICAL ITALIC SMALL FINAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D70E 𝜎 MATHEMATICAL ITALIC SMALL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D72E 𝜮 MATHEMATICAL BOLD ITALIC CAPITAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D747 𝝇 MATHEMATICAL BOLD ITALIC SMALL FINAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D748 𝝈 MATHEMATICAL BOLD ITALIC SMALL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D768 𝝨 MATHEMATICAL SANS-SERIF BOLD CAPITAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D781 𝞁 MATHEMATICAL SANS-SERIF BOLD SMALL FINAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D782 𝞂 MATHEMATICAL SANS-SERIF BOLD SMALL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D7A2 𝞢 MATHEMATICAL SANS-SERIF BOLD ITALIC CAPITAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D7BB 𝞻 MATHEMATICAL SANS-SERIF BOLD ITALIC SMALL FINAL SIGMA</li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+1D7BC 𝞼 MATHEMATICAL SANS-SERIF BOLD ITALIC SMALL SIGMA</li></ul> <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 reflist-lower-alpha"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-12"><a href="#cite_ref-12">^</a> Combined with <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r886049734">U+23B3 to make a double-high sigma </li> <li id="cite_note-13"><a href="#cite_ref-13">^</a> The MATHEMATICAL characters should only be used for math. Stylized Greek text should be encoded using the normal Greek letters, with markup and formatting to indicate text style. </li> </ol></div></div> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(4)"><h2 id="See_also">See also</h2></div><section class="mf-section-4 collapsible-block" id="mf-section-4"> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1237033735">@media print{body.ns-0 .mw-parser-output .sistersitebox{display:none!important}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .sistersitebox img[src*="Wiktionary-logo-en-v2.svg"]{background-color:white}}</style><div class="side-box side-box-right plainlinks sistersitebox"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409"> <div class="side-box-flex"> <div class="side-box-image"><noscript><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png" decoding="async" width="30" height="40" class="mw-file-element" data-file-width="1024" data-file-height="1376"></noscript><span class="lazy-image-placeholder" style="width: 30px;height: 40px;" data-src="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/30px-Commons-logo.svg.png" data-alt="" data-width="30" data-height="40" data-srcset="//upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/45px-Commons-logo.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/4/4a/Commons-logo.svg/59px-Commons-logo.svg.png 2x" data-class="mw-file-element"> </div> <div class="side-box-text plainlist">Wikimedia Commons has media related to <a href="https://commons.wikimedia.org/wiki/%CE%A3" class="extiw" title="commons:Σ">the letter sigma</a>.</div></div> </div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1235681985"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1237033735"><div class="side-box side-box-right plainlinks sistersitebox"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1126788409"> <div class="side-box-flex"> <div class="side-box-image"><noscript><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/40px-Wiktionary-logo-en-v2.svg.png" decoding="async" width="40" height="40" class="mw-file-element" data-file-width="512" data-file-height="512"></noscript><span class="lazy-image-placeholder" style="width: 40px;height: 40px;" data-src="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/40px-Wiktionary-logo-en-v2.svg.png" data-alt="" data-width="40" data-height="40" data-srcset="//upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/60px-Wiktionary-logo-en-v2.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/9/99/Wiktionary-logo-en-v2.svg/80px-Wiktionary-logo-en-v2.svg.png 2x" data-class="mw-file-element"> </div> <div class="side-box-text plainlist">Look up <a href="https://en.wiktionary.org/wiki/%CE%A3" class="extiw" title="wiktionary:Σ">Σ</a>, <a href="https://en.wiktionary.org/wiki/%CF%83" class="extiw" title="wiktionary:σ">σ</a>, or <a href="https://en.wiktionary.org/wiki/%CF%82" class="extiw" title="wiktionary:ς">ς</a> in Wiktionary, the free dictionary.</div></div> </div> <ul><li><a href="/wiki/Antisigma" class="mw-redirect" title="Antisigma">Antisigma</a></li> <li><a href="/wiki/Greek_letters_used_in_mathematics,_science,_and_engineering" title="Greek letters used in mathematics, science, and engineering">Greek letters used in mathematics, science, and engineering</a></li> <li><a href="/wiki/Sampi" title="Sampi">Sampi</a></li> <li><a href="/wiki/Sho_(letter)" title="Sho (letter)">Sho (letter)</a></li> <li><a href="/wiki/Stigma_(letter)" class="mw-redirect" title="Stigma (letter)">Stigma (letter)</a></li> <li><a href="/wiki/Sibilant_consonant" class="mw-redirect" title="Sibilant consonant">Sibilant consonant</a></li> <li><a href="/wiki/Summation" title="Summation">Summation</a> (Σ)</li> <li>Combining form "sigm-" (e.g. <a href="/wiki/Sigmodon" class="mw-redirect" title="Sigmodon">sigmodon</a>, <a href="/wiki/Sigmurethra" title="Sigmurethra">sigmurethra</a>, etc.)</li> <li>Derivative "<a href="/wiki/Sigmoid_(disambiguation)" class="mw-redirect mw-disambig" title="Sigmoid (disambiguation)">sigmoid</a>" (e.g. <a href="/wiki/Sigmoid_sinus" title="Sigmoid sinus">sigmoid sinus</a>, <a href="/wiki/Sigmoid_colon" title="Sigmoid colon">sigmoid colon</a>, <a href="/wiki/Sigmoidoscopy" title="Sigmoidoscopy">sigmoidoscopy</a>, etc.)</li> <li><a href="/wiki/Meme" title="Meme">Meme</a></li></ul> </section><div class="mw-heading mw-heading2 section-heading" onclick="mfTempOpenSection(5)"><h2 id="References">References</h2></div><section class="mf-section-5 collapsible-block" id="mf-section-5"> <div class="mw-heading mw-heading3"><h3 id="Notes">Notes</h3></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist reflist-lower-roman"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-3"><a href="#cite_ref-3">^</a> "the same letter, which the Dorians call "san", but the Ionians 'sigma'..." [translated from <a href="/wiki/Ancient_Greek" title="Ancient Greek">Ancient Greek</a>: "τὠυτὸ γράμμα, τὸ Δωριέες μὲν σὰν καλέουσι ,Ἴωνες δὲ σίγμα"] (<a href="/wiki/Herodotus" title="Herodotus">Herodotus</a> 1.139) </li> </ol></div></div> <div class="mw-heading mw-heading3"><h3 id="Citations">Citations</h3></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-1"><a href="#cite_ref-1">^</a> <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><cite id="CITEREFReference-OED-sigma" class="citation encyclopaedia cs1"><a rel="nofollow" class="external text" href="https://www.oed.com/search/dictionary/?q=sigma">"sigma"</a>. <a href="/wiki/Oxford_English_Dictionary" title="Oxford English Dictionary">Oxford English Dictionary</a> (Online ed.). <a href="/wiki/Oxford_University_Press" title="Oxford University Press">Oxford University Press</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=sigma&rft.btitle=Oxford+English+Dictionary&rft.edition=Online&rft.pub=Oxford+University+Press&rft_id=https%3A%2F%2Fwww.oed.com%2Fsearch%2Fdictionary%2F%3Fq%3Dsigma&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASigma" class="Z3988"> (Subscription or <a rel="nofollow" class="external text" href="https://www.oed.com/public/login/loggingin#withyourlibrary">participating institution membership</a> required.) </li> <li id="cite_note-woodard-2">^ <a href="#cite_ref-woodard_2-0">a</a> <a href="#cite_ref-woodard_2-1">b</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWoodard2006" class="citation encyclopaedia cs1">Woodard, Roger D. (2006). "Alphabet". In Wilson, Nigel Guy (ed.). Encyclopedia of Ancient Greece. London: Routledge. p. 38.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=Alphabet&rft.btitle=Encyclopedia+of+Ancient+Greece&rft.place=London&rft.pages=38&rft.pub=Routledge&rft.date=2006&rft.aulast=Woodard&rft.aufirst=Roger+D.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASigma" class="Z3988"> </li> <li id="cite_note-4"><a href="#cite_ref-4">^</a> <a href="/wiki/Herodotus" title="Herodotus">Herodotus</a>, <a href="/wiki/Histories_(Herodotus)" title="Histories (Herodotus)">Histories</a> 1.139 — <a href="/wiki/Michael_Everson" title="Michael Everson">Everson, Michael</a> and <a href="/wiki/Nicholas_Sims-Williams" title="Nicholas Sims-Williams">Nicholas Sims-Williams</a>. 2002. "<a rel="nofollow" class="external text" href="https://archive.today/20120628161421/http://www.tlg.uci.edu/~opoudjis/unicode/nonattic.html">Non-Attic letters</a>," transcribed by N. Nicholas. Archived from the <a rel="nofollow" class="external text" href="http://www.tlg.uci.edu/~opoudjis/unicode/nonattic.html">original</a> 2020-06-28. </li> <li id="cite_note-jeffery25-5"><a href="#cite_ref-jeffery25_5-0">^</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJeffery1961" class="citation book cs1">Jeffery, Lilian H. (1961). The Local Scripts of Archaic Greece. Oxford: Clarendon. pp. 25–7.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=The+Local+Scripts+of+Archaic+Greece&rft.place=Oxford&rft.pages=25-7&rft.pub=Clarendon&rft.date=1961&rft.aulast=Jeffery&rft.aufirst=Lilian+H.&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASigma" class="Z3988"> </li> <li id="cite_note-6"><a href="#cite_ref-6">^</a> Thompson, Edward M. (1912). Introduction to Greek and Latin Paleography. Oxford: Clarendon. p. 108, 144. </li> <li id="cite_note-7"><a href="#cite_ref-7">^</a> Hopkins, Edward C. D. (2004). "<a rel="nofollow" class="external text" href="http://www.parthia.com/fonts/letterforms_usage.htm">Letterform Usage | Numismatica Font Projects</a>" Parthia. </li> <li id="cite_note-8"><a href="#cite_ref-8">^</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFde_Lisle2020" class="citation journal cs1">de Lisle, Christopher (2020). <a rel="nofollow" class="external text" href="https://www.atticinscriptions.com/papers/aiuk-11/">"Attic Inscriptions in UK Collections: Ashmolean Museum, Oxford"</a>. AIUK. 11: 11. <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/2054-6769">2054-6769</a>. Retrieved 2 June 2022.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=AIUK&rft.atitle=Attic+Inscriptions+in+UK+Collections%3A+Ashmolean+Museum%2C+Oxford&rft.volume=11&rft.pages=11&rft.date=2020&rft.issn=2054-6769&rft.aulast=de+Lisle&rft.aufirst=Christopher&rft_id=https%3A%2F%2Fwww.atticinscriptions.com%2Fpapers%2Faiuk-11%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASigma" class="Z3988"> </li> <li id="cite_note-9"><a href="#cite_ref-9">^</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFFollet2000" class="citation journal cs1">Follet, Simone (2000). "Les deux archontes Pamménès du Ier siècle a.c. à Athènes". Revue des Études Grecques. 113: 188–192. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.3406%2Freg.2000.4402">10.3406/reg.2000.4402</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Revue+des+%C3%89tudes+Grecques&rft.atitle=Les+deux+archontes+Pamm%C3%A9n%C3%A8s+du+Ier+si%C3%A8cle+a.c.+%C3%A0+Ath%C3%A8nes&rft.volume=113&rft.pages=188-192&rft.date=2000&rft_id=info%3Adoi%2F10.3406%2Freg.2000.4402&rft.aulast=Follet&rft.aufirst=Simone&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASigma" class="Z3988"> </li> <li id="cite_note-10"><a href="#cite_ref-10">^</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFConroy2008" class="citation web cs1">Conroy, Kevin M. (21 February 2008). <a rel="nofollow" class="external text" href="http://dlib.bc.edu/islandora/object/bc-ir:102094">"Celtic initial consonant mutations - nghath and bhfuil?"</a> – via dlib.bc.edu.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Celtic+initial+consonant+mutations+-+nghath+and+bhfuil%3F&rft.date=2008-02-21&rft.aulast=Conroy&rft.aufirst=Kevin+M.&rft_id=http%3A%2F%2Fdlib.bc.edu%2Fislandora%2Fobject%2Fbc-ir%3A102094&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASigma" class="Z3988"> </li> <li id="cite_note-Hill1935-11"><a href="#cite_ref-Hill1935_11-0">^</a> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHill1935" class="citation journal cs1">Hill, A. V. (1935). <a rel="nofollow" class="external text" href="https://doi.org/10.1038%2F136222a0">"Units and Symbols"</a>. Nature. 136 (3432): 222. <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/1935Natur.136..222H">1935Natur.136..222H</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%2F136222a0">10.1038/136222a0</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:4087300">4087300</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature&rft.atitle=Units+and+Symbols&rft.volume=136&rft.issue=3432&rft.pages=222&rft.date=1935&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A4087300%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1038%2F136222a0&rft_id=info%3Abibcode%2F1935Natur.136..222H&rft.aulast=Hill&rft.aufirst=A.+V.&rft_id=https%3A%2F%2Fdoi.org%2F10.1038%252F136222a0&rfr_id=info%3Asid%2Fen.wikipedia.org%3ASigma" class="Z3988"> </li> </ol></div></div>    </section></div> <noscript><img src="https://login.m.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1&mobile=1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Sigma&oldid=1257429088">https://en.wikipedia.org/w/index.php?title=Sigma&oldid=1257429088</a>"</div></div> </div> <div class="post-content" id="page-secondary-actions"> </div> </main> <footer class="mw-footer minerva-footer" role="contentinfo"> <a class="last-modified-bar" href="/w/index.php?title=Sigma&action=history"> <div class="post-content last-modified-bar__content"> Last edited on 14 November 2024, at 21:20 </div> </a> <div class="post-content footer-content"> <div id='mw-data-after-content'> <div class="read-more-container"></div> </div> <div id="p-lang"> <h4>Languages</h4> <section> <ul id="p-variants" class="minerva-languages"></ul> <ul class="minerva-languages"><li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Sigma_(letter)" title="Sigma (letter) – Afrikaans" lang="af" hreflang="af" data-title="Sigma (letter)" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target">Afrikaans</a></li><li class="interlanguage-link interwiki-als mw-list-item"><a href="https://als.wikipedia.org/wiki/%CE%A3" title="Σ – Alemannic" lang="gsw" hreflang="gsw" data-title="Σ" data-language-autonym="Alemannisch" data-language-local-name="Alemannic" class="interlanguage-link-target">Alemannisch</a></li><li class="interlanguage-link interwiki-ab mw-list-item"><a href="https://ab.wikipedia.org/wiki/%CE%A3" title="Σ – Abkhazian" lang="ab" hreflang="ab" data-title="Σ" data-language-autonym="Аԥсшәа" data-language-local-name="Abkhazian" class="interlanguage-link-target">Аԥсшәа</a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B3%D9%8A%D8%BA%D9%85%D8%A7" title="سيغما – Arabic" lang="ar" hreflang="ar" data-title="سيغما" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target">العربية</a></li><li class="interlanguage-link interwiki-arc mw-list-item"><a href="https://arc.wikipedia.org/wiki/%CE%A3" title="Σ – Aramaic" lang="arc" hreflang="arc" data-title="Σ" data-language-autonym="ܐܪܡܝܐ" data-language-local-name="Aramaic" class="interlanguage-link-target">ܐܪܡܝܐ</a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Siqma" title="Siqma – Azerbaijani" lang="az" hreflang="az" data-title="Siqma" data-language-autonym="Azərbaycanca" data-language-local-name="Azerbaijani" class="interlanguage-link-target">Azərbaycanca</a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%B8%E0%A6%BF%E0%A6%97%E0%A6%AE%E0%A6%BE" title="সিগমা – Bangla" lang="bn" hreflang="bn" data-title="সিগমা" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target">বাংলা</a></li><li class="interlanguage-link interwiki-zh-min-nan mw-list-item"><a href="https://zh-min-nan.wikipedia.org/wiki/%CE%A3" title="Σ – Minnan" lang="nan" hreflang="nan" data-title="Σ" data-language-autonym="閩南語 / Bân-lâm-gú" data-language-local-name="Minnan" class="interlanguage-link-target">閩南語 / Bân-lâm-gú</a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%A1%D1%96%D0%B3%D0%BC%D0%B0_(%D0%BB%D1%96%D1%82%D0%B0%D1%80%D0%B0)" title="Сігма (літара) – Belarusian" lang="be" hreflang="be" data-title="Сігма (літара)" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target">Беларуская</a></li><li class="interlanguage-link interwiki-be-x-old mw-list-item"><a href="https://be-tarask.wikipedia.org/wiki/%D0%A1%D1%8B%D0%B3%D0%BC%D0%B0" title="Сыгма – Belarusian (Taraškievica orthography)" lang="be-tarask" hreflang="be-tarask" data-title="Сыгма" data-language-autonym="Беларуская (тарашкевіца)" data-language-local-name="Belarusian (Taraškievica orthography)" class="interlanguage-link-target">Беларуская (тарашкевіца)</a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0" title="Сигма – Bulgarian" lang="bg" hreflang="bg" data-title="Сигма" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target">Български</a></li><li class="interlanguage-link interwiki-bar mw-list-item"><a href="https://bar.wikipedia.org/wiki/Sigma" title="Sigma – Bavarian" lang="bar" hreflang="bar" data-title="Sigma" data-language-autonym="Boarisch" data-language-local-name="Bavarian" class="interlanguage-link-target">Boarisch</a></li><li class="interlanguage-link interwiki-bo mw-list-item"><a href="https://bo.wikipedia.org/wiki/%E0%BD%A6%E0%BD%B2%E0%BD%82%E0%BC%8B%E0%BD%98%E0%BC%8D" title="སིག་མ། – Tibetan" lang="bo" hreflang="bo" data-title="སིག་མ།" data-language-autonym="བོད་ཡིག" data-language-local-name="Tibetan" class="interlanguage-link-target">བོད་ཡིག</a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Sigma_(lizherenn)" title="Sigma (lizherenn) – Breton" lang="br" hreflang="br" data-title="Sigma (lizherenn)" data-language-autonym="Brezhoneg" data-language-local-name="Breton" class="interlanguage-link-target">Brezhoneg</a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Sigma" title="Sigma – Catalan" lang="ca" hreflang="ca" data-title="Sigma" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target">Català</a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Sigma" title="Sigma – Czech" lang="cs" hreflang="cs" data-title="Sigma" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target">Čeština</a></li><li class="interlanguage-link interwiki-sn mw-list-item"><a href="https://sn.wikipedia.org/wiki/%CE%A3" title="Σ – Shona" lang="sn" hreflang="sn" data-title="Σ" data-language-autonym="ChiShona" data-language-local-name="Shona" class="interlanguage-link-target">ChiShona</a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Sigma" title="Sigma – Welsh" lang="cy" hreflang="cy" data-title="Sigma" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target">Cymraeg</a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Sigma_(bogstav)" title="Sigma (bogstav) – Danish" lang="da" hreflang="da" data-title="Sigma (bogstav)" data-language-autonym="Dansk" data-language-local-name="Danish" class="interlanguage-link-target">Dansk</a></li><li class="interlanguage-link interwiki-se mw-list-item"><a href="https://se.wikipedia.org/wiki/%CE%A3" title="Σ – Northern Sami" lang="se" hreflang="se" data-title="Σ" data-language-autonym="Davvisámegiella" data-language-local-name="Northern Sami" class="interlanguage-link-target">Davvisámegiella</a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Sigma" title="Sigma – German" lang="de" hreflang="de" data-title="Sigma" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target">Deutsch</a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Sigma" title="Sigma – Estonian" lang="et" hreflang="et" data-title="Sigma" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target">Eesti</a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%A3%CE%AF%CE%B3%CE%BC%CE%B1" title="Σίγμα – Greek" lang="el" hreflang="el" data-title="Σίγμα" data-language-autonym="Ελληνικά" data-language-local-name="Greek" class="interlanguage-link-target">Ελληνικά</a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/%CE%A3" title="Σ – Spanish" lang="es" hreflang="es" data-title="Σ" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target">Español</a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Sigmo" title="Sigmo – Esperanto" lang="eo" hreflang="eo" data-title="Sigmo" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target">Esperanto</a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Sigma" title="Sigma – Basque" lang="eu" hreflang="eu" data-title="Sigma" data-language-autonym="Euskara" data-language-local-name="Basque" class="interlanguage-link-target">Euskara</a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%B3%DB%8C%DA%AF%D9%85%D8%A7" title="سیگما – Persian" lang="fa" hreflang="fa" data-title="سیگما" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target">فارسی</a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Sigma" title="Sigma – French" lang="fr" hreflang="fr" data-title="Sigma" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target">Français</a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Sigme" title="Sigme – Irish" lang="ga" hreflang="ga" data-title="Sigme" data-language-autonym="Gaeilge" data-language-local-name="Irish" class="interlanguage-link-target">Gaeilge</a></li><li class="interlanguage-link interwiki-gd mw-list-item"><a href="https://gd.wikipedia.org/wiki/Sigma" title="Sigma – Scottish Gaelic" lang="gd" hreflang="gd" data-title="Sigma" data-language-autonym="Gàidhlig" data-language-local-name="Scottish Gaelic" class="interlanguage-link-target">Gàidhlig</a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Sigma" title="Sigma – Galician" lang="gl" hreflang="gl" data-title="Sigma" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target">Galego</a></li><li class="interlanguage-link interwiki-hak mw-list-item"><a href="https://hak.wikipedia.org/wiki/%CE%A3" title="Σ – Hakka Chinese" lang="hak" hreflang="hak" data-title="Σ" data-language-autonym="客家語 / Hak-kâ-ngî" data-language-local-name="Hakka Chinese" class="interlanguage-link-target">客家語 / Hak-kâ-ngî</a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%CE%A3" title="Σ – Korean" lang="ko" hreflang="ko" data-title="Σ" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target">한국어</a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D5%8D%D5%AB%D5%A3%D5%B4%D5%A1_(%D5%BF%D5%A1%D5%BC)" title="Սիգմա (տառ) – Armenian" lang="hy" hreflang="hy" data-title="Սիգմա (տառ)" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target">Հայերեն</a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Sigma" title="Sigma – Croatian" lang="hr" hreflang="hr" data-title="Sigma" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target">Hrvatski</a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Sigma" title="Sigma – Indonesian" lang="id" hreflang="id" data-title="Sigma" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target">Bahasa Indonesia</a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Sigma" title="Sigma – Icelandic" lang="is" hreflang="is" data-title="Sigma" data-language-autonym="Íslenska" data-language-local-name="Icelandic" class="interlanguage-link-target">Íslenska</a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Sigma" title="Sigma – Italian" lang="it" hreflang="it" data-title="Sigma" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target">Italiano</a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%A1%D7%99%D7%92%D7%9E%D7%90" title="סיגמא – Hebrew" lang="he" hreflang="he" data-title="סיגמא" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target">עברית</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%92%E1%83%9B%E1%83%90_(%E1%83%90%E1%83%A1%E1%83%9D)" title="სიგმა (ასო) – Georgian" lang="ka" hreflang="ka" data-title="სიგმა (ასო)" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target">ქართული</a></li><li class="interlanguage-link interwiki-sw mw-list-item"><a href="https://sw.wikipedia.org/wiki/Sigma" title="Sigma – Swahili" lang="sw" hreflang="sw" data-title="Sigma" data-language-autonym="Kiswahili" data-language-local-name="Swahili" class="interlanguage-link-target">Kiswahili</a></li><li class="interlanguage-link interwiki-kv mw-list-item"><a href="https://kv.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0" title="Сигма – Komi" lang="kv" hreflang="kv" data-title="Сигма" data-language-autonym="Коми" data-language-local-name="Komi" class="interlanguage-link-target">Коми</a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/%CE%A3" title="Σ – Haitian Creole" lang="ht" hreflang="ht" data-title="Σ" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target">Kreyòl ayisyen</a></li><li class="interlanguage-link interwiki-ku mw-list-item"><a href="https://ku.wikipedia.org/wiki/Sigma" title="Sigma – Kurdish" lang="ku" hreflang="ku" data-title="Sigma" data-language-autonym="Kurdî" data-language-local-name="Kurdish" class="interlanguage-link-target">Kurdî</a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Sigma" title="Sigma – Latin" lang="la" hreflang="la" data-title="Sigma" data-language-autonym="Latina" data-language-local-name="Latin" class="interlanguage-link-target">Latina</a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Sigma" title="Sigma – Latvian" lang="lv" hreflang="lv" data-title="Sigma" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target">Latviešu</a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Sigma" title="Sigma – Luxembourgish" lang="lb" hreflang="lb" data-title="Sigma" data-language-autonym="Lëtzebuergesch" data-language-local-name="Luxembourgish" class="interlanguage-link-target">Lëtzebuergesch</a></li><li class="interlanguage-link interwiki-lez mw-list-item"><a href="https://lez.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0_(%D0%B3%D1%8C%D0%B0%D1%80%D1%84)" title="Сигма (гьарф) – Lezghian" lang="lez" hreflang="lez" data-title="Сигма (гьарф)" data-language-autonym="Лезги" data-language-local-name="Lezghian" class="interlanguage-link-target">Лезги</a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Sigma_(raid%C4%97)" title="Sigma (raidė) – Lithuanian" lang="lt" hreflang="lt" data-title="Sigma (raidė)" data-language-autonym="Lietuvių" data-language-local-name="Lithuanian" class="interlanguage-link-target">Lietuvių</a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Szigma" title="Szigma – Hungarian" lang="hu" hreflang="hu" data-title="Szigma" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target">Magyar</a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%B8%E0%B4%BF%E0%B4%97%E0%B5%8D%E0%B4%AE" title="സിഗ്മ – Malayalam" lang="ml" hreflang="ml" data-title="സിഗ്മ" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target">മലയാളം</a></li><li class="interlanguage-link interwiki-mr mw-list-item"><a href="https://mr.wikipedia.org/wiki/%E0%A4%B8%E0%A4%BF%E0%A4%97%E0%A5%8D%E0%A4%AE%E0%A4%BE" title="सिग्मा – Marathi" lang="mr" hreflang="mr" data-title="सिग्मा" data-language-autonym="मराठी" data-language-local-name="Marathi" class="interlanguage-link-target">मराठी</a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Sigma" title="Sigma – Malay" lang="ms" hreflang="ms" data-title="Sigma" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target">Bahasa Melayu</a></li><li class="interlanguage-link interwiki-cdo mw-list-item"><a href="https://cdo.wikipedia.org/wiki/Sigma" title="Sigma – Mindong" lang="cdo" hreflang="cdo" data-title="Sigma" data-language-autonym="閩東語 / Mìng-dĕ̤ng-ngṳ̄" data-language-local-name="Mindong" class="interlanguage-link-target">閩東語 / Mìng-dĕ̤ng-ngṳ̄</a></li><li class="interlanguage-link interwiki-nah mw-list-item"><a href="https://nah.wikipedia.org/wiki/%CE%A3" title="Σ – Nahuatl" lang="nah" hreflang="nah" data-title="Σ" data-language-autonym="Nāhuatl" data-language-local-name="Nahuatl" class="interlanguage-link-target">Nāhuatl</a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Sigma_(letter)" title="Sigma (letter) – Dutch" lang="nl" hreflang="nl" data-title="Sigma (letter)" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target">Nederlands</a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%CE%A3" title="Σ – Japanese" lang="ja" hreflang="ja" data-title="Σ" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target">日本語</a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Sigma" title="Sigma – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Sigma" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target">Norsk bokmål</a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Sigma" title="Sigma – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Sigma" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target">Norsk nynorsk</a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Sigma" title="Sigma – Occitan" lang="oc" hreflang="oc" data-title="Sigma" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target">Occitan</a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%B8%E0%A8%BF%E0%A8%97%E0%A8%AE%E0%A8%BE" title="ਸਿਗਮਾ – Punjabi" lang="pa" hreflang="pa" data-title="ਸਿਗਮਾ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="Punjabi" class="interlanguage-link-target">ਪੰਜਾਬੀ</a></li><li class="interlanguage-link interwiki-nds mw-list-item"><a href="https://nds.wikipedia.org/wiki/Sigma" title="Sigma – Low German" lang="nds" hreflang="nds" data-title="Sigma" data-language-autonym="Plattdüütsch" data-language-local-name="Low German" class="interlanguage-link-target">Plattdüütsch</a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Sigma" title="Sigma – Polish" lang="pl" hreflang="pl" data-title="Sigma" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target">Polski</a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/%CE%A3" title="Σ – Portuguese" lang="pt" hreflang="pt" data-title="Σ" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target">Português</a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Sigma_(liter%C4%83)" title="Sigma (literă) – Romanian" lang="ro" hreflang="ro" data-title="Sigma (literă)" data-language-autonym="Română" data-language-local-name="Romanian" class="interlanguage-link-target">Română</a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0_(%D0%B1%D1%83%D0%BA%D0%B2%D0%B0)" title="Сигма (буква) – Russian" lang="ru" hreflang="ru" data-title="Сигма (буква)" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target">Русский</a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Sigma" title="Sigma – Simple English" lang="en-simple" hreflang="en-simple" data-title="Sigma" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target">Simple English</a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Sigma" title="Sigma – Slovak" lang="sk" hreflang="sk" data-title="Sigma" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target">Slovenčina</a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Sigma" title="Sigma – Slovenian" lang="sl" hreflang="sl" data-title="Sigma" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target">Slovenščina</a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%D8%B3%DB%8C%DA%AF%D9%85%D8%A7" title="سیگما – Central Kurdish" lang="ckb" hreflang="ckb" data-title="سیگما" data-language-autonym="کوردی" data-language-local-name="Central Kurdish" class="interlanguage-link-target">کوردی</a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0_(%D1%81%D0%BB%D0%BE%D0%B2%D0%BE)" title="Сигма (слово) – Serbian" lang="sr" hreflang="sr" data-title="Сигма (слово)" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target">Српски / srpski</a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Sigma" title="Sigma – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Sigma" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target">Srpskohrvatski / српскохрватски</a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Sigma" title="Sigma – Finnish" lang="fi" hreflang="fi" data-title="Sigma" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target">Suomi</a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Sigma" title="Sigma – Swedish" lang="sv" hreflang="sv" data-title="Sigma" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target">Svenska</a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%8B%E0%B8%B4%E0%B8%81%E0%B8%A1%E0%B8%B2" title="ซิกมา – Thai" lang="th" hreflang="th" data-title="ซิกมา" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target">ไทย</a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Sigma" title="Sigma – Turkish" lang="tr" hreflang="tr" data-title="Sigma" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target">Türkçe</a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%A1%D0%B8%D0%B3%D0%BC%D0%B0" title="Сигма – Ukrainian" lang="uk" hreflang="uk" data-title="Сигма" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target">Українська</a></li><li class="interlanguage-link interwiki-vep mw-list-item"><a href="https://vep.wikipedia.org/wiki/Sigma" title="Sigma – Veps" lang="vep" hreflang="vep" data-title="Sigma" data-language-autonym="Vepsän kel’" data-language-local-name="Veps" class="interlanguage-link-target">Vepsän kel’</a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Sigma" title="Sigma – Vietnamese" lang="vi" hreflang="vi" data-title="Sigma" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target">Tiếng Việt</a></li><li class="interlanguage-link interwiki-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Sigma" title="Sigma – Waray" lang="war" hreflang="war" data-title="Sigma" data-language-autonym="Winaray" data-language-local-name="Waray" class="interlanguage-link-target">Winaray</a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%CE%A3" title="Σ – Wu" lang="wuu" hreflang="wuu" data-title="Σ" data-language-autonym="吴语" data-language-local-name="Wu" class="interlanguage-link-target">吴语</a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%CE%A3" title="Σ – Cantonese" lang="yue" hreflang="yue" data-title="Σ" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target">粵語</a></li><li class="interlanguage-link interwiki-diq mw-list-item"><a href="https://diq.wikipedia.org/wiki/%CE%A3" title="Σ – Zazaki" lang="diq" hreflang="diq" data-title="Σ" data-language-autonym="Zazaki" data-language-local-name="Zazaki" class="interlanguage-link-target">Zazaki</a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%CE%A3" title="Σ – Chinese" lang="zh" hreflang="zh" data-title="Σ" data-language-autonym="中文" data-language-local-name="Chinese" class="interlanguage-link-target">中文</a></li><li class="interlanguage-link interwiki-kge mw-list-item"><a href="https://kge.wikipedia.org/wiki/%CE%A3_(Sigma)" title="Σ (Sigma) – Komering" lang="kge" hreflang="kge" data-title="Σ (Sigma)" data-language-autonym="Kumoring" data-language-local-name="Komering" class="interlanguage-link-target">Kumoring</a></li></ul> </section> </div> <div class="minerva-footer-logo"><img src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" alt="Wikipedia" width="120" height="18" style="width: 7.5em; height: 1.125em;"/> </div> <ul id="footer-info" class="footer-info hlist hlist-separated"> <li id="footer-info-lastmod"> This page was last edited on 14 November 2024, at 21:20 (UTC).</li> <li id="footer-info-copyright">Content is available under <a class="external" rel="nofollow" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en">CC BY-SA 4.0</a> unless otherwise noted.</li> </ul> <ul id="footer-places" class="footer-places hlist hlist-separated"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a 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