The correlation functions of large-scale fluctuations are crucial observables in modern cosmology. There have been considerable efforts in the analytical study of cosmological correlators in recent years. In this talk, I will introduce the basic structure of cosmological correlators and several analytical methods we recently proposed for computing them. In particular, I will describe the family tree decomposition of arbitrary nested time integrals. With this method, we largely solve the problem of analytical computation of massive tree amplitudes in dS and conformal scalar tree amplitudes in a power-law FRW universe.

报告人简介

Zhong-Zhi Xianyu is an associate professor at the Department of Physics, Tsinghua University. He obtained his Ph.D. in 2015 from Tsinghua and was a postdoc at Harvard from 2015 to 2020. He works in theoretical particle physics and cosmology. His recent research interests include cosmological collider physics, quantum field theory and amplitude techniques in curved spacetime, new physics in the early universe and in astrophysical systems, gravitational wave astronomy, etc.

邀请人

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