Title: Bootstrap Our Way towards Inflationary New Physics

Speaker: Dong-Gang Wang 王东刚 (University of Cambridge)

Time: 2:00pm, Feb 14 (Tuesday) 2023

Location: 理科楼C302

Abstract: Cosmological correlation functions contain valuable information about the primordial Universe, with possible signatures of new physics at extremely high energies. Recently, the advances of the ”cosmological bootstrap” program offer new perspectives and powerful tools to study these primordial imprints. In this talk, I will apply the bootstrap approach to systematically classify the leading observational target — primordial three-point functions (bispectrum) from cosmic inflation. For the first time, we derive a complete set of scalar bispectra with new non-Gaussianity shapes and large signals. In particular, our analysis incorporates three distinct but phenomenologically important cases: i) the equilateral-type non-Gaussianities from single field inflation; ii) the cosmological colliders from massive exchange; iii) “local” non-Gaussianities from multi-field inflation. In addition, new phenomenologies are identified from the bootstrap analysis, which provide interesting targets for the data analysis of upcoming cosmological surveys.

Bio: Dong-Gang Wang is a postdoctoral researcher as a Rubicon Fellow at the Department of Applied Mathematics and Theoretical Physics in the University of Cambridge, UK. Before that, he did his PhD in Leiden University in the Netherlands for PhD as a de Sitter Fellow from 2016 to 2020. Before that, he was a master student in USTC from 2013 to 2016. His research mainly focuses on the primordial cosmology. In particular he is interested in dissecting non-Gaussian statistics of primordial fluctuations by using the effective field theory and bootstrap approaches.