Soubhik Kumar | Probing primordial fluctuations through stochastic gravitational wave background

8/4/22
Workshop on Phase Transitions and Topological Defects in the Early Universe

Speaker: Soubhik Kumar (UC Berkeley)

Title: Probing primordial fluctuations through stochastic gravitational wave background anisotropies

Abstract: Stochastic gravitational wave backgrounds are expected to be anisotropic. While such anisotropies can be of astrophysical origin, a cosmological component of such anisotropies can carry rich information about primordial perturbations. Focusing on the case of a cosmological phase transition, I will talk about how such anisotropies can give us a powerful probe of primordial non-Gaussianities, complementary to current and future CMB and LSS searches. In the scenario where astrophysical foregrounds are also present, I will then discuss some strategies using which we can extract the cosmological signal, focusing on the case of LISA, Taiji and BBO, in particular.