Colloquium / Seminars
Topic：Supertranslation invariance of angular momentum
Speaker：Prof. Ye-Kai Wang
(Dept. of Applied Mathematics, National Yang Ming Chiao Tung University)
Date time：Nov. 22, 2022 14:00 - 15:00
LIGO's successful detection of gravitational waves has revitalized the theoretical understanding of the angular momentum carried away by gravitational radiation. An infinite-dimensional "supertranslation ambiguity" has presented an essential difficulty for studying angular momentum at null infinity. In this talk, we will present a definition of angular momentum in general relativity that is supertranslation invariant. The new definition of angular momentum is derived from the limit of the Chen-Wang-Yau quasilocal angular momentum. The talk is based on joint work with Po-Ning Chen, Jordan Keller, Mu-Tao Wang and Shing-Tung Yau.