{"id":187177,"date":"2024-04-11T14:25:39","date_gmt":"2024-04-11T19:25:39","guid":{"rendered":"https:\/\/lifeboat.com\/blog\/2024\/04\/quintessence-physics"},"modified":"2024-04-11T14:25:39","modified_gmt":"2024-04-11T19:25:39","slug":"quintessence-physics","status":"publish","type":"post","link":"https:\/\/lifeboat.com\/blog\/2024\/04\/quintessence-physics","title":{"rendered":"Quintessence (physics)"},"content":{"rendered":"<p>In <a href=\"https:\/\/en.wikipedia.org\/wiki\/Physics\" title=\"Physics\">physics<\/a>, <b>quintessence<\/b> is a <a href=\"https:\/\/en.wikipedia.org\/wiki\/Hypothesis\" title=\"Hypothesis\">hypothetical<\/a> form of <a href=\"https:\/\/en.wikipedia.org\/wiki\/Dark_energy\" title=\"Dark energy\">dark energy<\/a>, more precisely a <a href=\"https:\/\/en.wikipedia.org\/wiki\/Scalar_field\" title=\"Scalar field\">scalar field<\/a>, postulated as an explanation of the observation of an <a href=\"https:\/\/en.wikipedia.org\/wiki\/Accelerating_expansion_of_the_universe\" title=\"Accelerating expansion of the universe\">accelerating rate of expansion<\/a> of the universe. The first example of this scenario was proposed by <a href=\"https:\/\/en.wikipedia.org\/wiki\/Bharat_Ratra\" title=\"Bharat Ratra\">Ratra<\/a> and <a href=\"https:\/\/en.wikipedia.org\/wiki\/Jim_Peebles\" title=\"Jim Peebles\">Peebles<\/a> (1988)<sup id=\u201d cite_ref-RatraPeebles1988_1-0\u201d class=\u201d reference\u201d>[1]<\/sup> and <a href=\"https:\/\/en.wikipedia.org\/wiki\/Christof_Wetterich\" title=\"Christof Wetterich\">Wetterich<\/a> (1988).<sup id=\u201d cite_ref-2\u201d class=\u201d reference\u201d>[2]<\/sup><sup id=\u201d cite_ref-3\u201d class=\u201d reference\u201d>[3]<\/sup> The concept was expanded to more general types of time-varying dark energy, and the term \u201cquintessence\u201d was first introduced in a 1998 paper by <a href=\"https:\/\/en.wikipedia.org\/wiki\/Robert_R._Caldwell\" title=\"Robert R. Caldwell\">Robert R. Caldwell<\/a>, Rahul Dave and <a href=\"https:\/\/en.wikipedia.org\/wiki\/Paul_Steinhardt\" title=\"Paul Steinhardt\">Paul Steinhardt<\/a>.<sup id=\u201d cite_ref-CDS_4-0\u201d class=\u201d reference\u201d>[4]<\/sup> It has been proposed by some physicists to be a <a href=\"https:\/\/en.wikipedia.org\/wiki\/Fifth_force\" title=\"Fifth force\">fifth fundamental force<\/a>.<sup id=\u201d cite_ref-5\u201d class=\u201d reference\u201d>[5]<\/sup><sup id=\u201d cite_ref-6\u201d class=\u201d reference\u201d>[6]<\/sup><sup id=\u201d cite_ref-7\u201d class=\u201d reference\u201d>[7]<\/sup><sup id=\u201d cite_ref-8\u201d class=\u201d reference\u201d>[8]<\/sup> Quintessence differs from the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Cosmological_constant\" title=\"Cosmological constant\">cosmological constant<\/a> explanation of dark energy in that it is dynamic; that is, it changes over time, unlike the cosmological constant which, by definition, does not change. Quintessence can be either attractive or repulsive depending on the ratio of its kinetic and potential energy. Those working with this postulate believe that quintessence became repulsive about ten billion years ago, about 3.5 billion years after the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Big_Bang\" title=\"Big Bang\">Big Bang<\/a>.<sup id=\u201d cite_ref-9\u201d class=\u201d reference\u201d>[9]<\/sup><\/p>\n<p>A group of researchers argued in 2021 that observations of the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Hubble_tension\" class=\"\" title=\"Hubble tension\">Hubble tension<\/a> may imply that only quintessence models with a nonzero <a href=\"https:\/\/en.wikipedia.org\/wiki\/Coupling_constant\" title=\"Coupling constant\">coupling constant<\/a> are viable.<sup id= cite_ref-FLRW_breakdown_10-0 class= reference>[10]<\/sup>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>In physics, quintessence is a hypothetical form of dark energy, more precisely a scalar field, postulated as an explanation of the observation of an accelerating rate of expansion of the universe. The first example of this scenario was proposed by Ratra and Peebles (1988)[1] and Wetterich (1988).[2][3] The concept was expanded to more general types [\u2026]<\/p>\n","protected":false},"author":661,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[33,1617],"tags":[],"class_list":["post-187177","post","type-post","status-publish","format-standard","hentry","category-cosmology","category-quantum-physics"],"_links":{"self":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/187177","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/users\/661"}],"replies":[{"embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/comments?post=187177"}],"version-history":[{"count":0,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/posts\/187177\/revisions"}],"wp:attachment":[{"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/media?parent=187177"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/categories?post=187177"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lifeboat.com\/blog\/wp-json\/wp\/v2\/tags?post=187177"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}