HET seminar: Geoffrey Compère
Speaker: Geoffrey Compère
Title: BMS Vacua and Black Holes
Abstract: I will first review the memory effect in GR and its connection to BMS supertranslations. I will discuss one classical construction of the class of inequivalent BMS vacua and inequivalent Schwarzschild black holes (with supertranslation memory), which are distinguished by classical superrotation charges. I will also discuss the details of the toy model of 3d gravity where the conjectured antipodal matching boundary conditions of Strominger between the BMS group at past and future null infinity can be proven exactly using canonical methods.