{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T03:09:05Z","timestamp":1773716945407,"version":"3.50.1"},"reference-count":63,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,11,12]],"date-time":"2022-11-12T00:00:00Z","timestamp":1668211200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100016047","name":"Science Fund of the Republic of Serbia","doi-asserted-by":"publisher","award":["7745968"],"award-info":[{"award-number":["7745968"]}],"id":[{"id":"10.13039\/501100016047","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100016047","name":"Science Fund of the Republic of Serbia","doi-asserted-by":"publisher","award":["CEECIND\/04594\/2017\/CP1393\/CT000"],"award-info":[{"award-number":["CEECIND\/04594\/2017\/CP1393\/CT000"]}],"id":[{"id":"10.13039\/501100016047","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100016047","name":"Science Fund of the Republic of Serbia","doi-asserted-by":"publisher","award":["UIDB\/50008\/2020"],"award-info":[{"award-number":["UIDB\/50008\/2020"]}],"id":[{"id":"10.13039\/501100016047","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["7745968"],"award-info":[{"award-number":["7745968"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["CEECIND\/04594\/2017\/CP1393\/CT000"],"award-info":[{"award-number":["CEECIND\/04594\/2017\/CP1393\/CT000"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e Tecnologia","doi-asserted-by":"publisher","award":["UIDB\/50008\/2020"],"award-info":[{"award-number":["UIDB\/50008\/2020"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015494","name":"Instituto de Telecomunica\u00e7\u00f5es","doi-asserted-by":"publisher","award":["7745968"],"award-info":[{"award-number":["7745968"]}],"id":[{"id":"10.13039\/501100015494","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015494","name":"Instituto de Telecomunica\u00e7\u00f5es","doi-asserted-by":"publisher","award":["CEECIND\/04594\/2017\/CP1393\/CT000"],"award-info":[{"award-number":["CEECIND\/04594\/2017\/CP1393\/CT000"]}],"id":[{"id":"10.13039\/501100015494","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100015494","name":"Instituto de Telecomunica\u00e7\u00f5es","doi-asserted-by":"publisher","award":["UIDB\/50008\/2020"],"award-info":[{"award-number":["UIDB\/50008\/2020"]}],"id":[{"id":"10.13039\/501100015494","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Universe"],"abstract":"<jats:p>We give a general overview of various flavours of the equivalence principle in classical and quantum physics, with special emphasis on the so-called weak equivalence principle, and contrast its validity in mechanics versus field theory. We also discuss its generalisation to a theory of quantum gravity. Our analysis suggests that only the strong equivalence principle can be considered fundamental enough to be generalised to a quantum gravity context since all other flavours of equivalence principle hold only approximately already at the classical level.<\/jats:p>","DOI":"10.3390\/universe8110598","type":"journal-article","created":{"date-parts":[[2022,11,14]],"date-time":"2022-11-14T04:24:10Z","timestamp":1668399850000},"page":"598","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Equivalence Principle in Classical and Quantum Gravity"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9345-4321","authenticated-orcid":false,"given":"Nikola","family":"Paunkovi\u0107","sequence":"first","affiliation":[{"name":"Instituto de Telecomunica\u00e7\u00f5es and Departamento de Matem\u00e1tica, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Avenida Rovisco Pais 1, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6977-4870","authenticated-orcid":false,"given":"Marko","family":"Vojinovi\u0107","sequence":"additional","affiliation":[{"name":"Institute of Physics, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"L89","DOI":"10.1088\/0264-9381\/15\/12\/003","article-title":"Decoherence of macroscopic closed systems within Newtonian quantum gravity","volume":"15","author":"Kay","year":"1998","journal-title":"Class. 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