{"id":9643,"date":"2023-02-03T17:02:00","date_gmt":"2023-02-03T16:02:00","guid":{"rendered":"https:\/\/scienceetonnante.com\/?p=9643"},"modified":"2023-02-03T17:04:20","modified_gmt":"2023-02-03T16:04:20","slug":"structures-grande-echelle","status":"publish","type":"post","link":"https:\/\/scienceetonnante.com\/blog\/2023\/02\/03\/structures-grande-echelle\/","title":{"rendered":"Les structures \u00e0 grande \u00e9chelle de l&rsquo;Univers"},"content":{"rendered":"<p>Dans la vid\u00e9o du jour, je vous parle de la myst\u00e9rieuse et fascinante structure \u00e0 grande \u00e9chelle de l&rsquo;Univers !<\/p>\n<p><iframe title=\"Les plus GRANDES structures de l&#039;Univers\" width=\"770\" height=\"433\" data-src=\"https:\/\/www.youtube.com\/embed\/l_mYUOhIOMg?feature=oembed\" frameborder=\"0\" allow=\"accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share\" allowfullscreen src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" class=\"lazyload\" data-load-mode=\"1\"><\/iframe><\/p>\n<p>Une fois n&rsquo;est pas coutume, en faisant la passe finale sur le script de cette vid\u00e9o, j&rsquo;ai carr\u00e9ment vir\u00e9 des passages entiers que j&rsquo;avais pourtant d\u00e9j\u00e0 \u00e9crits, en me disant que \u00e7a rendrait la vid\u00e9o trop lourde et trop d\u00e9cousue. Voici donc quelques compl\u00e9ments et des r\u00e9f\u00e9rences bibliographiques pour celles et ceux qui veulent creuser.<\/p>\n<p><strong>Revues g\u00e9n\u00e9rales<\/strong><\/p>\n<p><em>Springel, Volker, Carlos S. Frenk, and Simon DM White. \u00ab\u00a0The large-scale structure of the Universe.\u00a0\u00bb nature 440.7088 (2006): 1137-1144.<\/em><\/p>\n<p><em>Angulo, Raul E., and Oliver Hahn. \u00ab\u00a0Large-scale dark matter simulations.\u00a0\u00bb Living Reviews in Computational Astrophysics 8.1 (2022): 1.<\/em><\/p>\n<p>Et <a href=\"https:\/\/campuspress.yale.edu\/astro610\/\" target=\"_blank\" rel=\"noopener\">le cours de Franck van den Bosch \u00e0 Yale<\/a> qui est tr\u00e8s complet (merci \u00e0 Maxime Trebitsch pour cette r\u00e9f !).<\/p>\n<p><strong>Sur les observations<\/strong><\/p>\n<p><em>Geller, Margaret J., and John P. Huchra. \u00ab\u00a0Mapping the universe.\u00a0\u00bb Science 246.4932 (1989): 897-903.<\/em><\/p>\n<p><em>Colless, Matthew, et al. \u00ab\u00a0The 2df galaxy redshift survey: spectra and redshifts.\u00a0\u00bb Monthly Notices of the Royal Astronomical Society 328.4 (2001): 1039-1063.<\/em><\/p>\n<p><em>Percival, Will J., et al. \u00ab\u00a0The 2dF Galaxy Redshift Survey: the power spectrum and the matter content of the Universe.\u00a0\u00bb Monthly Notices of the Royal Astronomical Society 327.4 (2001): 1297-1306.<\/em><\/p>\n<p><em>Eisenstein, Daniel J., et al. \u00ab\u00a0SDSS-III: Massive spectroscopic surveys of the distant universe, the Milky Way, and extra-solar planetary systems.\u00a0\u00bb The Astronomical Journal 142.3 (2011): 72.<\/em><\/p>\n<p><strong>Simulations<\/strong><\/p>\n<p><em>Aarseth, Sverre J., J. Richard Gott III, and Edwin L. Turner. \u00ab\u00a0N-body simulations of galaxy clustering. I-Initial conditions and galaxy collapse times.\u00a0\u00bb The Astrophysical Journal 228 (1979): 664-683.<\/em><\/p>\n<p><em>Davis, Marc, et al. \u00ab\u00a0The evolution of large-scale structure in a universe dominated by cold dark matter.\u00a0\u00bb Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 292, May 15, 1985, p. 371-394.<\/em><\/p>\n<p><em>Efstathiou, George, et al. \u00ab\u00a0Numerical techniques for large cosmological N-body simulations.\u00a0\u00bb The Astrophysical Journal Supplement Series 57 (1985): 241-260.<\/em><\/p>\n<p><em>Springel, Volker, et al. \u00ab\u00a0Simulations of the formation, evolution and clustering of galaxies and quasars.\u00a0\u00bb nature 435.7042 (2005): 629-636.<\/em><\/p>\n<h3>Les for\u00eats Lyman-alpha<\/h3>\n<p>Parmi la longue liste de sujets coup\u00e9s : je voulais donner des d\u00e9tails sur les for\u00eats Lyman-alpha des quasars, et puis j&rsquo;ai finalement trouv\u00e9 que \u00e7a ne collait pas bien au flot global. Je pense que je ferai un jour une vid\u00e9o sur les quasars. Mais le m\u00e9canisme est tr\u00e8s chouette, en gros la raie Lyman-alpha de l&rsquo;hydrog\u00e8ne (transition entre les niveaux 1 et 2) est normalement \u00e0 121nm. Avec le redshift, elle appara\u00eet d\u00e9cal\u00e9e d&rsquo;un facteur (1+z).<\/p>\n<p>Par exemple ici la raie \u00e0 121nm se trouve d\u00e9cal\u00e9e vers 440nm.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-9651 lazyload\" data-src=\"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/lyman-hs01051619.gif\" alt=\"\" width=\"841\" height=\"263\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 841px; --smush-placeholder-aspect-ratio: 841\/263;\" \/><\/p>\n<p>Mais le spectre est plein de trous du fait de l&rsquo;absorption par nuages interm\u00e9diaires a des redshifts diff\u00e9rents. Et chaque trou nous renseigne sur la pr\u00e9sence d&rsquo;une masse d&rsquo;hydrog\u00e8ne \u00e0 une certaine distance.<\/p>\n<h3>Les oscillations acoustiques des baryons<\/h3>\n<p>J&rsquo;ai souvent eu l&rsquo;occasion de montrer le spectre de puissance du rayonnement fossile. Le premier pic correspond \u00e0 un pic d&rsquo;oscillation acoustique qui d\u00e9pend de la pr\u00e9sence de mati\u00e8re baryonique et de mati\u00e8re noire.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-9649 lazyload\" data-src=\"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/The-CMB-power-spectrum-as-seen-by-Planck-76-The-red-dots-with-error-bars-are-the-data.png\" alt=\"\" width=\"850\" height=\"513\" data-srcset=\"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/The-CMB-power-spectrum-as-seen-by-Planck-76-The-red-dots-with-error-bars-are-the-data.png 850w, https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/The-CMB-power-spectrum-as-seen-by-Planck-76-The-red-dots-with-error-bars-are-the-data-300x181.png 300w\" data-sizes=\"(max-width: 850px) 100vw, 850px\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 850px; --smush-placeholder-aspect-ratio: 850\/513;\" \/><\/p>\n<p>&nbsp;<\/p>\n<p>Si on extrapole ce pic de fluctuation \u00e0 l&rsquo;Univers actuel, cela doit se traduire par une l\u00e9g\u00e8re bosse dans la fonction de corr\u00e9lation de la mati\u00e8re baryonique.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-9647 lazyload\" data-src=\"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/baryon_acoustic_peak.png\" alt=\"\" width=\"574\" height=\"574\" data-srcset=\"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/baryon_acoustic_peak.png 574w, https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/baryon_acoustic_peak-300x300.png 300w, https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/baryon_acoustic_peak-150x150.png 150w, https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/baryon_acoustic_peak-370x370.png 370w\" data-sizes=\"(max-width: 574px) 100vw, 574px\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 574px; --smush-placeholder-aspect-ratio: 574\/574;\" \/><\/p>\n<p>Une fa\u00e7on \u00ab\u00a0artistique\u00a0\u00bb et visuellement exag\u00e9r\u00e9e de repr\u00e9senter cela dans la r\u00e9partition des galaxies<\/p>\n<p><img decoding=\"async\" class=\"aligncenter size-large wp-image-9648 lazyload\" data-src=\"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/BOSS-BAO-1024x657.jpg\" alt=\"\" width=\"770\" height=\"494\" data-srcset=\"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/BOSS-BAO-1024x657.jpg 1024w, https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/BOSS-BAO-300x192.jpg 300w, https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/BOSS-BAO-1536x986.jpg 1536w\" data-sizes=\"(max-width: 770px) 100vw, 770px\" src=\"data:image\/svg+xml;base64,PHN2ZyB3aWR0aD0iMSIgaGVpZ2h0PSIxIiB4bWxucz0iaHR0cDovL3d3dy53My5vcmcvMjAwMC9zdmciPjwvc3ZnPg==\" style=\"--smush-placeholder-width: 770px; --smush-placeholder-aspect-ratio: 770\/494;\" \/><\/p>\n<p>Cette oscillation acoustique des baryons n&rsquo;a \u00e9t\u00e9 mise en \u00e9vidence dans la fonction de corr\u00e9lation de la mati\u00e8re qu&rsquo;avec SDSS.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Dans la vid\u00e9o du jour, je vous parle de la myst\u00e9rieuse et fascinante structure \u00e0 grande \u00e9chelle de l&rsquo;Univers ! Une fois n&rsquo;est pas coutume, en faisant la passe finale sur le script de cette vid\u00e9o, j&rsquo;ai carr\u00e9ment vir\u00e9 des passages entiers que j&rsquo;avais pourtant d\u00e9j\u00e0 \u00e9crits, en me disant que \u00e7a rendrait la vid\u00e9o<\/p>\n","protected":false},"author":1,"featured_media":9645,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[6],"tags":[46],"class_list":{"0":"post-9643","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-physique","8":"tag-cosmologie"},"jetpack_featured_media_url":"https:\/\/scienceetonnante.com\/blog\/wp-content\/uploads\/2023\/02\/blog.png","jetpack_sharing_enabled":true,"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/posts\/9643","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/comments?post=9643"}],"version-history":[{"count":9,"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/posts\/9643\/revisions"}],"predecessor-version":[{"id":9657,"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/posts\/9643\/revisions\/9657"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/media\/9645"}],"wp:attachment":[{"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/media?parent=9643"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/categories?post=9643"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/scienceetonnante.com\/blog\/wp-json\/wp\/v2\/tags?post=9643"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}