Quasi-Local Mass in a Binary Black Hole Merger

11/14/2023 11:00 am - 12:00 pm

General Relativity Seminar

Speaker: Daniel KolbĀ (Max Planck Institute)

Title: Quasi-Local Mass in a Binary Black Hole Merger

Abstract: One of the major open problems in classical general relativity is how one should define the mass of a finite region of space. In this talk, we will investigate a promising definition proposed by Wang and Yau in 2009. A closed 2-surface bounding the region of interest is embedded isometrically into Minkowski space. The mass is then calculated by comparing the extrinsic geometries. The Wang-Yau mass has many desirable properties, but it has previously not been calculated for surfaces in dynamical spacetimes. To remedy this, we will discuss how the Wang-Yau mass can be computed in practice and extend the definition to surfaces important in black hole dynamics: their quasi-local horizons. Finally, we look at how this mass behaves in a merger of black holes.