Noether current from surface term, Virasoro algebra and black hole entropy in bigravity

TL;DR

This paper investigates black hole entropy in bigravity theory using Virasoro algebra and surface terms, revealing how massive spin-2 fields influence entropy and confirming the Schwarzschild solution under specific conditions.

Contribution

It introduces a novel approach to compute black hole entropy in bigravity via Virasoro algebra and surface terms, highlighting the role of massive spin-2 fields.

Findings

Schwarzschild solution exists for C^2=1 in bigravity

Massive spin-2 fields affect black hole entropy

Virasoro algebra approach successfully computes entropy in bigravity

Abstract

We consider the static, spherically symmetric black hole solutions in bigravity theory for minimal model with a condition $f_{\mu \nu} = C^{2} g_{\mu \nu}$ and evaluate the entropy for black holes. In this condition, we show that there exists the Schwarzschild solution for $C^{2} = 1$, which is unique consistent solution. We examine how the massive spin-2 field contributes and affects to the Bekenstein-Hawking entropy corresponding to Einstein gravity. In order to obtain the black hole entropy, we use a recently proposed approach which use Virasoro algebra and central charge corresponding to surface term in the gravitational action.