Physics | NIST

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<div class="nist-block nist-block--no-margin"> <div class="entity-reference"> <img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/images/2021/05/07/Physics-1200x248.jpg" width="1200" height="248" alt="purple rings around orange core" typeof="foaf:Image"/> </div> </div> </div> <div class="nist-section-header__main grid-container"> <div class="grid-row"> <div class="nist-section-header__title"> <h1 class="nist-page__title">Physics</h1> </div> </div> </div> </div> </div> <div class="grid-container"> <div class="nist-page__region nist-page__region--topic-description padding-top-4 margin-top-1"> <div class="nist-region-heading"> <h2>Overview</h2> </div> <div class="grid-row"> <div class="tablet:grid-col-8 padding-right-5 margin-bottom-4"> <div class="text-with-summary"> <p>Physics research at NIST includes everything from improving the safety of medical radiation procedures to developing future "quantum information" technologies that generate unbreakable codes. NIST provides the measurements, standards, and technical expertise scientists and industries need to push the limits of the fundamental properties of nature.</p> </div> </div> <div class="tablet:grid-col-4"> <div class="nist-block nist-block--no-margin"> <h2 class="nist-block__title">Featured Content</h2> <div class="nist-field nist-field--label-hidden nist-field--link-list link font-sans-sm"> <div class="nist-field__items"> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/measuring-cosmos">Measuring the Cosmos</a></div> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/nist-and-nobel">NIST and the Nobel</a></div> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/pml/productsservices/physical-reference-data">Physical Reference Data</a></div> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/topics/physics/what-are-optical-lattices">What Are Optical Lattices?</a></div> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/topics/physics/optical-frequency-combs">What Is an Optical Frequency Comb?</a></div> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/physics/what-planck-constant">What Is the Planck Constant?</a></div> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/physics/what-are-imaging-phantoms">What Are Imaging Phantoms?</a></div> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/si-redefinition">SI Redefinition</a></div> </div> </div> </div> </div> </div> </div> </div> <div class="bg-base-lightest padding-y-5 margin-y-4"> <div class="nist-page__region nist-page__region--topic-list grid-container"> <div class="views-element-container nist-block margin-bottom-0"> <div><div class="js-view-dom-id-71d63e989a18ac6eb06381303be352858359731149029b93d68e14cafd981172"> <div class="nist-block margin-bottom-0"> <div class="nist-region-heading"> <h2>Physics Topics</h2> </div> <ul class="add-list-reset link-list"> <div class="grid-row"> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/atomic-molecular-quantum" hreflang="en">Atomic / molecular / quantum</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/biological-physics" hreflang="en">Biological physics</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/condensed-matter" hreflang="en">Condensed matter</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/electron-physics" hreflang="en">Electron physics</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/magnetics" hreflang="en">Magnetics</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/nuclear-physics" hreflang="en">Nuclear physics</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/optical-physics-and-communications" hreflang="en">Optical physics and communications</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/quantum-information-science" hreflang="en">Quantum information science</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/radiation" hreflang="en">Radiation</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/spectroscopy" hreflang="en">Spectroscopy</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/thermodynamics" hreflang="en">Thermodynamics</a></div></div></li> </div> <div class="tablet:grid-col-6"> <li class="font-sans-md padding-bottom-205"><div class="views-field views-field-field-shared-section"><div class="field-content nist-icon nist-icon--before nist-icon--arrow-right2"><a href="/web/20231128043209/https://www.nist.gov/time-frequency" hreflang="en">Time & frequency</a></div></div></li> </div> </div> </ul> </div> </div> </div> </div> </div> </div> <div class="nist-page__region nist-page__region--main"> <div class="nist-block"> <div class="grid-container margin-y-5"> <div class="paragraph paragraph--type--topic-text paragraph--view-mode--default"> <div class="nist-region-heading"> <h2> Key Accomplishments </h2> </div> <div class="tablet-lg:grid-col-8 padding-right-5"> <div class="text-long"><ul><li><span><span><span><strong>Atomic clocks:</strong> NIST built the world’s <a href="https://web.archive.org/web/20231128043209/http://ieeemilestones.ethw.org/Milestones:First_Atomic_Clock">first atomic clock</a>, showing how to achieve the precise synchronization now critical to many modern technology systems, from GPS satellites for navigation to stock exchanges. NIST continues to operate atomic clocks, including the <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="96f9b944-2096-47cd-b87f-e2739001847e" href="/web/20231128043209/https://www.nist.gov/news-events/news/2014/04/nist-launches-new-us-time-standard-nist-f2-atomic-clock" title="NIST Launches a New U.S. Time Standard: NIST-F2 Atomic Clock">U.S. civilian time standard</a><span><span>.</span></span></span></span></span></li> <li><span><span><span><strong>Frequency combs:</strong> NIST scientists developed the <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="d0f3e23a-9ded-41b4-b75e-df0223888093" href="/web/20231128043209/https://www.nist.gov/topics/physics/optical-frequency-combs" title="Optical Frequency Combs">frequency comb</a>, a “ruler of light” that made possible the latest atomic clocks, which may serve as future time standards. Frequency comb applications are also helping to find Earth-like planets, identify atmospheric chemicals and locate gas leaks. </span></span></span></li> <li><span><span><span><strong>Laser cooling:</strong> NIST physicists led the development and application of methods of cooling and trapping atoms with laser light, leading to the creation of new states of matter, advances in experimental quantum computing, and the awarding of three related <a data-entity-substitution="canonical" data-entity-type="node" data-entity-uuid="6daf17eb-c260-43ba-9978-0f3800926007" href="/web/20231128043209/https://www.nist.gov/nist-and-nobel" title="NIST and The Nobel">Nobel Prizes</a> to NIST physicists.</span></span></span></li> </ul></div> </div> </div> </div> <div class="grid-container margin-y-5"> <div class="paragraph paragraph--type--topic-research paragraph--view-mode--default"> <div class="nist-region-heading"> <h2>The Research</h2> </div> <div class="grid-row"> <div class="tablet:grid-col-8 padding-right-5 margin-y-2"> <h2 class="nist-block__title">Projects & Programs</h2> <article about="/programs-projects/yb-optical-lattice-clock" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20231128043209/https://www.nist.gov/programs-projects/yb-optical-lattice-clock" hreflang="en"><img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2023/04/27/yb-optical-clock.png?itok=mF-uVQQ3" width="100" height="67" alt="yb optical clock" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20231128043209/https://www.nist.gov/programs-projects/yb-optical-lattice-clock"><span>Yb Optical Lattice Clock</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> The very best atomic clocks today are known as optical clocks, because their timebase resides at a very high frequency (~10 15 Hz), corresponding to the optical </div> </div> </div> </article> <article about="/programs-projects/exposure-notification-protecting-workplaces-and-vulnerable-communities-during" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20231128043209/https://www.nist.gov/programs-projects/exposure-notification-protecting-workplaces-and-vulnerable-communities-during" hreflang="en"><img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2020/07/24/deviceab.png?itok=-cEpWJm6" width="100" height="59" alt="device a and device b" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20231128043209/https://www.nist.gov/programs-projects/exposure-notification-protecting-workplaces-and-vulnerable-communities-during"><span>Exposure Notification – protecting workplaces and vulnerable communities during a pandemic</span> </a></h3> <div class="nist-teaser__type"> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> The goal of this project is to utilize NIST expertise in privacy, cybersecurity, machine learning, wireless technology, ranging, modeling, and hardware and </div> </div> </div> </article> <article about="/programs-projects/quantum-pascal-fixed-length-optical-cavity-floc-pressure-standards" class="nist-teaser"> <div class="nist-teaser__image"> <div class="entity-reference"> <a href="/web/20231128043209/https://www.nist.gov/programs-projects/quantum-pascal-fixed-length-optical-cavity-floc-pressure-standards" hreflang="en"><img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/thumbnail/public/images/2021/04/20/floc_0.jpg?itok=-AD-m7gF" width="64" height="100" alt="FLOC" typeof="foaf:Image"/> </a> </div> </div> <div class="nist-teaser__content-wrapper"> <header> <h3 class="nist-teaser__title"><a href="/web/20231128043209/https://www.nist.gov/programs-projects/quantum-pascal-fixed-length-optical-cavity-floc-pressure-standards"><span>Quantum Pascal: Fixed Length Optical Cavity (FLOC) Pressure Standards</span> </a></h3> <div class="nist-teaser__type"> <div class="nist-badge display-inline-block margin-y-1 nist-badge--blue boolean">Ongoing</div> </div> </header> <div class="nist-teaser__content"> <div class="text-long"> This project is fundamentally changing the method for realizing and disseminating the SI unit of pressure, the pascale (Pa). The underlying principal behind </div> </div> </div> </article> <div class="link-list"><a href="/web/20231128043209/https://www.nist.gov/laboratories/projects-programs/topic/249241">View All Projects/Programs</a></div> </div> <div class="tablet:grid-col-4 margin-y-2"> <h2 class="nist-block__title">Additional Resources Links</h2> <div class="nist-field nist-field--label-hidden nist-field--link-list link nist-field--link-list font-sans-sm"> <div class="nist-field__items"> <div class="nist-field__item"><a href="/web/20231128043209/https://www.nist.gov/publications/search?ta%5B0%5D=249241&ta%5B1%5D=249241">Publications</a></div> </div> </div> </div> </div> </div> </div> <div class="paragraph paragraph--type--topic-featured paragraph--view-mode--default nist-content-row--width-full bg-base-lightest margin-y-5"> <div class="grid-container"> <div class="nist-card nist-card--horizontal nist-card--horizontal-full nist-card--base-lightest"> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20231128043209/https://www.nist.gov/measuring-cosmos"> <div class="entity-reference"> <figure class="nist-image"> <img src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2021/10/14/AdvACT_MF_array_edge%20%281%29.jpg.webp?itok=FCB5E19v" width="800" height="400" alt="Closeup of metallic plate shows circular sensors. " loading="lazy" typeof="foaf:Image"/> <figcaption class="nist-image__caption"> <div data-caption-editable="true" class="nist-image__caption-content"> </div> </figcaption> </figure> </div> </a> </div> <div class="nist-card__title"> <h3> Measuring the Cosmos </h3> </div> <div class="nist-card__content"> <div class="text-long"><p>Scientists around the world use state-of-the-art telescopes to understand our universe. </p> <p>Take a look under the hood and see the NIST technology that helps answer many cosmic questions.</p></div> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20231128043209/https://www.nist.gov/measuring-cosmos" class="usa-button ">Learn more</a> </div> </div> </div> </div> </div> </div> <div class="grid-container margin-y-4"> <div class="nist-region-heading"> <h2>News</h2> </div> <div class="margin-bottom-5"> <div class="entity-reference"> <div class="nist-card nist-card--horizontal nist-card--horizontal-full"> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20231128043209/https://www.nist.gov/blogs/taking-measure/keeping-time-nist"> <div class="entity-reference"> <img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/600w_x_360h/public/images/2020/06/18/nist_physicist_elizabeth_donley_featured%20image.jpg.webp?itok=WvT8tD3X" width="600" height="360" alt="NIST physicist Elizabeth Donley and Compact Atomic Clock" typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title"> <h3><span>Keeping Time at NIST</span> </h3> </div> <div class="nist-card__content"> <div class="text-with-summary"> Einstein is reported to have once said that time is what a clock measures. Some say that what we experience as time is really our experience of the phenomenon of entropy, the second law of thermodynamics. Entropy, loosely explained, is the tendency for things to become disorganized. Hot coffee always goes cold. It never reheats itself. Eggs don’t unscramble themselves. Your room gets messy and you </div> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20231128043209/https://www.nist.gov/blogs/taking-measure/keeping-time-nist" class="usa-button ">Read more</a> </div> </div> </div> </div> </div> </div> <div class="paragraph paragraph--type--dynamic-news-list-topic paragraph--view-mode--default"> <div class="views-element-container"><div class="js-view-dom-id-ee6c538f2ef0afd2957ed251c3ab2f6652a9cbe06b97714d133b4d5fa8d5f880"> <div class="grid-row grid-gap-2"> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20231128043209/https://www.nist.gov/news-events/news/2023/10/new-frequency-comb-can-identify-molecules-20-nanosecond-snapshots"> <div class="entity-reference"> <img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2023/10/30/Rainbow.png.webp?itok=DPBhUXvJ" width="800" height="400" alt="Colorful 3D graph shows peak in center with red spikes and lower portions in blue." typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title padding-y-5"> <h3><span property="schema:name">New Frequency Comb Can Identify Molecules in 20-Nanosecond Snapshots</span> </h3> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20231128043209/https://www.nist.gov/news-events/news/2023/10/new-frequency-comb-can-identify-molecules-20-nanosecond-snapshots" class="usa-button ">Read more</a> </div> </div> </div> </div> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20231128043209/https://www.nist.gov/news-events/news/2023/10/partially-unraveling-entangled-mystery"> <div class="entity-reference"> <img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2023/10/26/graph_state.png.webp?itok=x5r7AYRz" width="800" height="400" alt="regular graph state illustration" typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title padding-y-5"> <h3><span property="schema:name">Partially unraveling an entangled mystery</span> </h3> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20231128043209/https://www.nist.gov/news-events/news/2023/10/partially-unraveling-entangled-mystery" class="usa-button ">Read more</a> </div> </div> </div> </div> <div class="nist-card tablet:grid-col-4 nist-card--topic "> <div class="nist-card__inner"> <div class="nist-card__image"> <a href="/web/20231128043209/https://www.nist.gov/news-events/news/2023/10/twisted-science-nist-researchers-find-new-quantum-ruler-explore-exotic"> <div class="entity-reference"> <img loading="lazy" src="/web/20231128043209im_/https://www.nist.gov/sites/default/files/styles/800w_x_400h/public/images/2023/09/28/Quantum_Moire_Illustration_960x600_v5.png.webp?itok=TEHSnc_7" width="800" height="400" alt="Illustration depicts two bilayers (two double layers) of graphene" typeof="foaf:Image"/> </div> </a> </div> <div class="nist-card__title padding-y-5"> <h3><span property="schema:name">Twisted Science: NIST Researchers Find a New Quantum Ruler to Explore Exotic Matter</span> </h3> </div> <div class="nist-card__links"> <div class="nist-card__button"> <a href="/web/20231128043209/https://www.nist.gov/news-events/news/2023/10/twisted-science-nist-researchers-find-new-quantum-ruler-explore-exotic" class="usa-button ">Read more</a> </div> </div> </div> </div> </div> <footer> <div class="link-list"><a href="/web/20231128043209/https://www.nist.gov/news-events/news-updates/topic/249241">View All News and Updates</a></div> </footer> </div> </div> </div> </div> <div class="padding-5 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