11–13 May 2026
University of Pittsburgh
US/Eastern timezone

Spectator Composes Gravitational Canon

12 May 2026, 14:15
15m
David Lawrence Hall 104, University of Pittsburgh

David Lawrence Hall 104, University of Pittsburgh

Particle Cosmology Cosmology

Speaker

Yunjia Bao (University of Chicago)

Description

We propose a general framework in which a phase transition is triggered during cosmic inflation by the slow-roll dynamics of a spectator field. The topological defects formed at the transition are inflated outside the horizon, reenter it after inflation, and can subsequently generate characteristic gravitational-wave (GW) signals. Quantum fluctuations of the spectator field modulate the timing of the transition, imprinting large-scale anisotropies in the resulting GW background. As an explicit realization, the spectator field may be identified with the Higgs field in a supersymmetric Standard Model. More generally, our framework applies to a wide class of spectator-modulated phenomena, providing a generic mechanism for producing anisotropic GW signals.

Authors

Keisuke Harigaya Yunjia Bao (University of Chicago)

Presentation materials

There are no materials yet.