{"id":386,"date":"2025-05-18T14:20:40","date_gmt":"2025-05-18T14:20:40","guid":{"rendered":"https:\/\/ybginat.com\/?page_id=386"},"modified":"2025-10-04T09:30:41","modified_gmt":"2025-10-04T09:30:41","slug":"relativistic-effects-in-large-scale-structure","status":"publish","type":"page","link":"https:\/\/ybginat.com\/index.php\/relativistic-effects-in-large-scale-structure\/","title":{"rendered":"Relativistic Effects in Large-Scale Structure"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-page\" data-elementor-id=\"386\" class=\"elementor elementor-386\" data-elementor-post-type=\"page\">\n\t\t\t\t\t\t<section class=\"elementor-section elementor-top-section elementor-element elementor-element-a76e925 elementor-section-boxed elementor-section-height-default elementor-section-height-default\" data-id=\"a76e925\" data-element_type=\"section\" data-e-type=\"section\">\n\t\t\t\t\t\t<div class=\"elementor-container elementor-column-gap-default\">\n\t\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-c2206f1\" data-id=\"c2206f1\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-cf94abb elementor-widget elementor-widget-text-editor\" data-id=\"cf94abb\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p dir=\"auto\" style=\"margin-bottom: 16px; color: #1f2328; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji';\">The observed distribution of galaxies on the sky provides a plethora of cosmological information, both on the evolution of the Universe and on large-scale structure. To interpret these observations however, we need to relate the observed galaxy sky positions and redshifts to the underlying space-time and matter distribution, a relation which is nontrivial even on very large scales, because of general relativity: the Universe is not exactly homogeneous and isotropic, and this deviation from an exact FLRW space-time distorts its own image. Light from galaxies is distorted (lensed, redshifted) by the large-scale structure &#8211; by the very distribution that we seek to observe.<\/p>\n<p dir=\"auto\" style=\"margin-bottom: 16px; color: #1f2328; font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans', Helvetica, Arial, sans-serif, 'Apple Color Emoji', 'Segoe UI Emoji';\">The papers Ginat et al. (2021),&nbsp;<a style=\"color: #214f78;\" href=\"https:\/\/iopscience.iop.org\/article\/10.1088\/1475-7516\/2021\/12\/031\" target=\"_blank\" rel=\"noopener\">JCAP12(2021)031<\/a>&nbsp;and Villey, Ginat et al.,&nbsp;<a style=\"color: #214f78;\" href=\"https:\/\/ui.adsabs.harvard.edu\/abs\/2025arXiv250611260V\/abstract\">arXiv:2506.11260<\/a>&nbsp;(2025) seek to study these effects, with the help of the &#8220;cosmic ruler&#8221; formulation of large-scale structure observables. The second calculates the cosmic rulers explicitly at second order in cosmological perturbation theory &#8211; no mean feat!<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t<div class=\"elementor-column elementor-col-50 elementor-top-column elementor-element elementor-element-d6a9596\" data-id=\"d6a9596\" data-element_type=\"column\" data-e-type=\"column\">\n\t\t\t<div class=\"elementor-widget-wrap elementor-element-populated\">\n\t\t\t\t\t\t<div class=\"elementor-element elementor-element-a95217d elementor-widget elementor-widget-image\" data-id=\"a95217d\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"image.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t\t\t\t<figure class=\"wp-caption\">\n\t\t\t\t\t\t\t\t\t\t<img fetchpriority=\"high\" decoding=\"async\" width=\"800\" height=\"600\" src=\"https:\/\/ybginat.com\/wp-content\/uploads\/2025\/10\/c_ell.png\" class=\"attachment-large size-large wp-image-397\" alt=\"\" srcset=\"https:\/\/ybginat.com\/wp-content\/uploads\/2025\/10\/c_ell.png 875w, https:\/\/ybginat.com\/wp-content\/uploads\/2025\/10\/c_ell-300x225.png 300w, https:\/\/ybginat.com\/wp-content\/uploads\/2025\/10\/c_ell-768x576.png 768w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/>\t\t\t\t\t\t\t\t\t\t\t<figcaption class=\"widget-image-caption wp-caption-text\">From: Ginat et al. JCAP12(2021)031<\/figcaption>\n\t\t\t\t\t\t\t\t\t\t<\/figure>\n\t\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>The observed distribution of galaxies on the sky provides a plethora of cosmological information, both on the evolution of the Universe and on large-scale structure. To interpret these observations however, we need to relate the observed galaxy sky positions and redshifts to the underlying space-time and matter distribution, a relation which is nontrivial even on [&hellip;]<\/p>\n","protected":false},"author":5,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-386","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/pages\/386","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/comments?post=386"}],"version-history":[{"count":10,"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/pages\/386\/revisions"}],"predecessor-version":[{"id":400,"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/pages\/386\/revisions\/400"}],"wp:attachment":[{"href":"https:\/\/ybginat.com\/index.php\/wp-json\/wp\/v2\/media?parent=386"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}