Seminar:- Cosmological Correlators in the Mirror
Parity violation in the early universe holds great promise for uncovering new physics. In particular, the primordial scalar four-point correlation function is allowed to develop a parity-violating component when massive spinning particles coupled to a helical chemical potential. In the first part of talk, the speaker will present when inflaton has a reduced sound speed, the dynamics admits an effective non-local description which yields a compact parity-odd trispectrum template in terms of elementary functions. For general case which allows for the exchange of additional states of any mass and integer spin, he will introduce a decomposition of the inflationary bulk-bulk propagator of massive spinning fields which ensures the time-ordered contributions are purely real after rotating to Euclidean time. Building on this decomposition, he will demonstrate that the parity-odd correlators are always factorized at the tree-level under the assumption of scale invariance.
講者：Dr. ZHU Yu-Hang (博士後研究, 韓國 基礎科學研究院*)
*Postdoc, Institute of Basic Science(기초과학연구원) in Korea