{"id":641776,"date":"2026-01-05T05:05:18","date_gmt":"2026-01-05T05:05:18","guid":{"rendered":"https:\/\/www.europesays.com\/fr\/641776\/"},"modified":"2026-01-05T05:05:18","modified_gmt":"2026-01-05T05:05:18","slug":"une-loi-pilier-de-lastrophysique-vient-detre-balayee-par-une-nouvelle-etude","status":"publish","type":"post","link":"https:\/\/www.europesays.com\/fr\/641776\/","title":{"rendered":"Une loi \u00ab\u00a0pilier\u00a0\u00bb de l&rsquo;astrophysique vient d&rsquo;\u00eatre balay\u00e9e par une nouvelle \u00e9tude"},"content":{"rendered":"<p class=\"sc-9e1vpx-0 jVoltE\">L\u2019\u00e9tude d\u00e9montre que le lien entre la luminosit\u00e9 \u00e0 2 keV et celle \u00e0 2500 \u00c5 varie de mani\u00e8re syst\u00e9matique avec le d\u00e9calage vers le rouge. Quand l\u2019Univers \u00e9tait plus jeune, la relation \u00e9tait plus plate et son \u00e9talement intrins\u00e8que plus faible. Antonis Georgakakis, coauteur de l\u2019article, explique que \u00ab cette non-universalit\u00e9 remet en question notre compr\u00e9hension de la croissance et du rayonnement des trous noirs supermassifs \u00bb. Les m\u00e9canismes qui transf\u00e8rent l\u2019\u00e9nergie du disque d\u2019accr\u00e9tion vers la couronne chaude ont donc probablement chang\u00e9 au fil des derniers milliards d\u2019ann\u00e9es.<\/p>\n<p class=\"sc-9e1vpx-0 jVoltE\">Voil\u00e0 qui entre en collision avec l\u2019hypoth\u00e8se d\u2019une relation fixe, qui servait notamment de fondement \u00e0 l\u2019utilisation des quasars comme sondes pour mesurer l\u2019expansion de l\u2019Univers. La m\u00e9thode employ\u00e9e, un cadre hi\u00e9rarchique bay\u00e9sien, a permis de traiter ensemble les d\u00e9tections et les non-d\u00e9tections en rayons X, ce qui a r\u00e9duit les biais des \u00e9tudes pr\u00e9c\u00e9dentes. Maria Chira, premi\u00e8re auteure, souligne que cette approche statistique robuste a rendu visible une tendance qui serait autrement rest\u00e9e cach\u00e9e.&#13;<\/p>\n","protected":false},"excerpt":{"rendered":"L\u2019\u00e9tude d\u00e9montre que le lien entre la luminosit\u00e9 \u00e0 2 keV et celle \u00e0 2500 \u00c5 varie de&hellip;\n","protected":false},"author":2,"featured_media":641777,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[1011,27,43,40,41,39,42,44],"class_list":{"0":"post-641776","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-sciences-et-technologies","8":"tag-fr","9":"tag-france","10":"tag-science","11":"tag-science-and-technology","12":"tag-sciences","13":"tag-sciences-et-technologies","14":"tag-technologies","15":"tag-technology"},"share_on_mastodon":{"url":"https:\/\/pubeurope.com\/@fr\/115840753575900006","error":""},"_links":{"self":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/posts\/641776","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/comments?post=641776"}],"version-history":[{"count":0,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/posts\/641776\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/media\/641777"}],"wp:attachment":[{"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/media?parent=641776"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/categories?post=641776"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.europesays.com\/fr\/wp-json\/wp\/v2\/tags?post=641776"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}