{"id":31654,"date":"2025-07-12T16:12:50","date_gmt":"2025-07-12T16:12:50","guid":{"rendered":"https:\/\/medexperts.pro\/?p=31654"},"modified":"2025-07-12T16:25:48","modified_gmt":"2025-07-12T16:25:48","slug":"daniel-kleppner-physicist-who-brought-precision-to-gps-dies-at-92","status":"publish","type":"post","link":"https:\/\/medexperts.pro\/?p=31654","title":{"rendered":"Daniel Kleppner, Physicist Who Brought Precision to GPS, Dies at 92"},"content":{"rendered":"
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He worked to develop an atomic clock that is essential to global positioning systems and helped confirm a rare state of matter predicted by Albert Einstein.<\/p>\n

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Daniel Kleppner, an experimental physicist who helped to develop an atomic clock that became an essential part of global positioning systems, or GPS, and who also helped to discover a rare fundamental state of matter predicted by Albert Einstein and his fellow theoretical physicist Satyendra Nath Bose, died on June 16 in Palo Alto, Calif. He was 92.<\/p>\n

His wife, Beatrice, confirmed the death. She said he collapsed while visiting their daughter, Sofie Kleppner, and her son, Darwin, who was graduating from high school.<\/p>\n

It was in the mid-1950s, while he was doing a fellowship at the University of Cambridge in England, that Dr. Kleppner learned something surprising: It was possible, a tutor told him, to build a clock precise enough to detect the effects of gravity on time. Curious, he went in search of more information and read Norman Ramsey<\/a>\u2019s 1953 book \u201cNuclear Moments.\u201d<\/p>\n

After his fellowship, he went on to do graduate work at Harvard University, where he discovered that Dr. Ramsey was on the faculty. He immediately applied for Dr. Ramsey\u2019s research group and was accepted.<\/p>\n<\/div>\n<\/div>\n

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Dr. Ramsey would eventually share the 1989 Nobel Prize in Physics for research he had done in the 1940s, when he discovered a way to measure the frequencies of electromagnetic radiation absorbed by atoms and molecules. His experimental technique laid the groundwork for nuclear magnetic resonance, a precursor to the M.R.I. technology used in medicine today.<\/p>\n

The atoms of each element vibrate at a unique frequency, like the signature call of a bird. Dr. Ramsey\u2019s work made it possible for scientists to build what is known as an atomic clock \u2014 a device that measures those vibrations, using the information to keep incredibly precise time. (The official measure of a second, for example, is 9,192,631,770 oscillations of a cesium atom.)<\/p>\n

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He worked to develop an atomic clock that is essential to global positioning systems and helped confirm a rare state of matter predicted by Albert Einstein.Daniel Kleppner, an experimental physicist who helped to develop an atomic clock that became an essential part of global positioning systems, or GPS, and who also helped to discover a rare fundamental state of matter predicted by Albert Einstein and his fellow theoretical physicist Satyendra Nath Bose, died on June 16 in Palo Alto, Calif. He was 92.His wife, Beatrice, confirmed the death. She said he collapsed while visiting their daughter, Sofie Kleppner, and her son, Darwin, who was graduating from high school.It was in the mid-1950s, while he was doing a fellowship at the University of Cambridge in England, that Dr. Kleppner learned something surprising: It was possible, a tutor told him, to build a clock precise enough to detect the effects of gravity on time. Curious, he went in search of more information and read Norman Ramsey\u2019s 1953 book \u201cNuclear Moments.\u201dAfter his fellowship, he went on to do graduate work at Harvard University, where he discovered that Dr. Ramsey was on the faculty. He immediately applied for Dr. Ramsey\u2019s research group and was accepted.Dr. Ramsey would eventually share the 1989 Nobel Prize in Physics for research he had done in the 1940s, when he discovered a way to measure the frequencies of electromagnetic radiation absorbed by atoms and molecules. His experimental technique laid the groundwork for nuclear magnetic resonance, a precursor to the M.R.I. technology used in medicine today.The atoms of each element vibrate at a unique frequency, like the signature call of a bird. Dr. Ramsey\u2019s work made it possible for scientists to build what is known as an atomic clock \u2014 a device that measures those vibrations, using the information to keep incredibly precise time. (The official measure of a second, for example, is 9,192,631,770 oscillations of a cesium atom.)We are having trouble retrieving the article content.Please enable JavaScript in your browser settings.Thank you for your patience while we verify access. If you are in Reader mode please exit and\u00a0log into\u00a0your Times account, or\u00a0subscribe\u00a0for all of The Times.Thank you for your patience while we verify access.Already a subscriber?\u00a0Log in.Want all of The Times?\u00a0Subscribe.<\/p>\n","protected":false},"author":1,"featured_media":31656,"comment_status":"close","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[34],"tags":[],"class_list":["post-31654","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-science"],"_links":{"self":[{"href":"https:\/\/medexperts.pro\/index.php?rest_route=\/wp\/v2\/posts\/31654","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/medexperts.pro\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/medexperts.pro\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/medexperts.pro\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/medexperts.pro\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=31654"}],"version-history":[{"count":2,"href":"https:\/\/medexperts.pro\/index.php?rest_route=\/wp\/v2\/posts\/31654\/revisions"}],"predecessor-version":[{"id":31657,"href":"https:\/\/medexperts.pro\/index.php?rest_route=\/wp\/v2\/posts\/31654\/revisions\/31657"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/medexperts.pro\/index.php?rest_route=\/wp\/v2\/media\/31656"}],"wp:attachment":[{"href":"https:\/\/medexperts.pro\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=31654"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/medexperts.pro\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=31654"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/medexperts.pro\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=31654"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}