Gravity seminar - Mu-Tao Wang  Seminar

Abstract:

The definition of angular momentum in general relativity has been a subtle issue since the 1960’s, due to the discovery of
"supertranslation ambiguity”: the angular momentums recorded by two distant observers of the same system may not be the same.
In this talk, I shall show how the mathematical theory of optimal isometric embedding and quasilocal angular momentum identifies a correction term,
and leads to a new definition of angular momentum that is free of any supertranslation ambiguity.
This is based on joint work with Po-Ning Chen, Jordan Keller, Ye-Kai Wang, and Shing-Tung Yau.