Title: Spacetime harmonic functions and applications to relativity

Speaker: Sven Hirsch (Duke University)

Abstract:

One of the central results in mathematical relativity is the spacetime positive mass theorem which asserts that the ADM energy-momentum of an initial data set satisfying the dominant energy condition is non-spacelike. This theorem has been proven by Schoen-Yau using the Jang equation, Witten using spinors and later by Eichmair-Huang-Lee-Schoen using MOTS. Based on level sets of spacetime harmonic functions we give another proof of this result which also gives a new lower bound for the mass. This is joint work with Demetre Kazaras and Marcus Khuri.