{"id":2539,"date":"2025-06-05T20:03:53","date_gmt":"2025-06-05T11:03:53","guid":{"rendered":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/?p=2539"},"modified":"2025-06-05T20:03:53","modified_gmt":"2025-06-05T11:03:53","slug":"2025-06-18","status":"publish","type":"post","link":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/2025\/06\/05\/2025-06-18\/","title":{"rendered":"2025-06-18"},"content":{"rendered":"\n<h2 class=\"wp-block-heading\"><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-bright-blue-color\">Secondary gravitational waves induced by primordial curvature perturbations<\/mark><\/h2>\n\n\n\n<p class=\"has-text-align-right\">Speaker: Takahiro Terada (Nagoya University)<\/p>\n\n\n\n<p>Abstract:<\/p>\n\n\n\n<p>The direct detection of gravitational waves (GWs) marked the beginning of the era of GW and multi-messenger astronomy. In addition to astrophysical sources, we can consider the stochastic GW background as a powerful probe of the early Universe, thereby promoting the development of GW cosmology. \u00a0In this talk, I will focus on secondary GWs induced by primordial curvature perturbations, which are generated at second order in cosmological perturbation theory. These GWs carry information about small-scale primordial fluctuations that are inaccessible to cosmic microwave background and large-scale structure observations. \u00a0I will explain their physical origin and cosmological significance. For instance, such GWs can probe inflationary models\u2014especially those predicting primordial black holes\u2014as well as the thermal history of the Universe. I will also discuss the relevance of secondary GWs in light of recent results from pulsar timing arrays and highlight prospects for future observations.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Secondary gravitational waves induced by primordial curvature perturbations Speaker: Takahiro Terada (Nagoya U &hellip; <a href=\"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/2025\/06\/05\/2025-06-18\/\" class=\"more-link\"><span class=\"screen-reader-text\">&#8220;2025-06-18&#8221; \u306e<\/span>\u7d9a\u304d\u3092\u8aad\u3080<\/a><\/p>\n","protected":false},"author":31,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-2539","post","type-post","status-publish","format-standard","hentry","category-1"],"_links":{"self":[{"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/posts\/2539","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/users\/31"}],"replies":[{"embeddable":true,"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/comments?post=2539"}],"version-history":[{"count":1,"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/posts\/2539\/revisions"}],"predecessor-version":[{"id":2540,"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/posts\/2539\/revisions\/2540"}],"wp:attachment":[{"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/media?parent=2539"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/categories?post=2539"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sci.nao.ac.jp\/seminars\/colloquium\/wp-json\/wp\/v2\/tags?post=2539"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}