报告题目 (Title)：CGMB(Cosmic Gravitational Microwave Backgrounds) and the dEGB (dilaton-Einstein-Gauss-Bonnet) Cosmology（宇宙引力微波背景与爱因斯坦-高斯-博内宇宙学）
报告人 (Speaker)： Bum-Hoon Lee（韩国西江大学）
报告时间 (Time)：2026年4月9日（周四）10:00
报告地点 (Place)：校本部 G楼313会议室
邀请人(Inviter)：葛先辉，尹璐
报告摘要：We begin by presenting the motivation for frameworks beyond Einstein's gravity and the ΛCDM paradigm, both from the theoretical and observational aspects . Sources and detectors of Gravitational Waves (GWs) are briefly reviewed with GWs as a tool for testing or constraining theories especially beyond Einstein's General Relativity theory. The main focus is on the CGMB from the hot plasmas in the early universe whose pea frequency is close to 100GHz. Next, our discussion will be on the cosmology of dilaton-Einstein-Gauss-Bonnet (DEGB) gravity. This represents one of the simplest extensions through the inclusion of higher-curvature terms. Particular attention is given to the emergence of a novel phase within dEGB cosmology at high temperatures, supplementing the established radiation, matter, and dark energy-dominated phases characteristic of the ΛCDM model. Out of the many implication of dEGB cosmology, we describe the impact to the CGMB from the hot plasmas consisting of the standard model particles in the early universe. The sources and propagation of the GWs depend on the gravity theory. We point out that CGMB can be enhanced up to the visible range for the detectors near future with the present technology. This should lead either to the new discovery of the Ultra High Frequency gravitational waves of CGMB or the constraints to the DEGB theory if not.
