Diffeomorphism on the horizon as an asymptotic isometry of the Schwarzschild black hole

Abstract

It is argued that the diffeomorphism on the horizontal sphere can be regarded\nas a nontrivial asymptotic isometry of the Schwarzschild black hole. We propose\na new boundary condition of asymptotic metrics near the horizon and show that\nthe condition admits the local time-shift and diffeomorphism on the horizon as\nthe asymptotic symmetry.\n