Title:Recent developments in black hole perturbation theory

Speaker:Sam Wong 黃崇清 (City University of Hong Kong)

Time:1:30 pm，Nov 21 (Thursday) 2024

Venue:Room W105,  Physics Building

Abstract:In various stages of black hole binary mergers, black hole perturbation theory is crucial for understanding the resulting gravitational waves. Notably, the ringdown phase of the final black hole is effectively characterized by quasinormal modes. This talk will begin by exploring modern techniques, such as effective field theory (EFT), for analyzing black hole quasinormal modes. In the second part, we will examine tidal deformations of black holes, characterized by Love numbers. The Love numbers of a black hole influence the inspiral waveform, providing a means to differentiate between a black hole and other compact objects. We will discuss their significance within the EFT framework of gravity, as well as the constraints imposed by ultraviolet (UV) completions in quantum field theory. Finally, we will address the intriguing phenomenon of the vanishing Love numbers in the context of nonlinear perturbation theory.

Bio:Dr. Sam Wong received his BSc and PhD from HKUST. He pursued a postdoctoral position at Columbia University from 2017 to 2019.After that, he has continued to investigate the mysteries of black holes and the early universe as a postdoctoral fellow at the Center for Particle Cosmology at the University of Pennsylvania from 2019 to 2023. Since 2023, he has been an Assistant Professor at the City University of Hong Kong. Dr. Wong’s research interests are diverse but all focused on probing the fundamental laws of nature. He aims to contribute to the advancement of their field by studying the structure of black holes and the earliest moments of the universe's existence, with the hope of uncovering new insights and expanding our knowledge.