Webinar
Title: Phase Transitions in an Expanding Universe: Stochastic Gravitational Waves in Standard and Non-Standard Histories
Speaker: Dr. Huaike Guo (郭怀珂) (University of Oklahoma)
Time: 10:00 (Beijing Time), Tuesday, 2020-8-11
Zoom: https://zoom.us/j/2151583083
Zoom ID:2151583083
Abstract: Primordial gravitational waves from first order cosmological phase transitions has become a new cosmic frontier to probe particle physics beyond the standard model and can complement current direct searches at the energy and intensity frontiers. I will briefly review recent developments of the theoretical modelling and numerical simulations of the gravitational wave production during a first order phase transition. I will then discuss in detail the modelling of the dominant acoustic production, our recent generalization of this framework into an expanding universe(hep-ph/2007.08537) and in particular the modified gravitational wave spectrum from sound waves. I will also discuss the changes due to non-standard cosmic expansions, the imprints of which on the gravitational wave signals might serve as cosmic witnesses of their existence.