Black Hole Thermodynamics Based on Unitary Evolutions

TL;DR

This paper proposes a new framework for black hole thermodynamics based on quantum unitary evolutions, challenging traditional entropy concepts and resolving information paradoxes by incorporating quantum metric perturbations.

Contribution

It introduces a unitary evolution approach to black hole thermodynamics, including quantum metric perturbations, and offers a resolution to the information loss and firewall paradoxes.

Findings

Black hole entropy may not be purely thermal or Boltzmann.

Including quantum metric perturbations allows a unitary description of black hole evolution.

Black hole thermodynamics can be reconstructed via statistical mechanics.

Abstract

In this paper, we try to construct black hole thermodynamics based on the fact that, the formation and evaporation of a black hole can be described by quantum unitary evolutions. First, we show that the Bekenstein-Hawking entropy $S_{BH}$ may not be a Boltzmann or thermal entropy. To confirm this statement, we show that the original black hole's "first law" may not simply be treated as the first law of thermodynamics formally, due to some missing metric perturbations caused by matter. Then, by including those (quantum) metric perturbations, we show that the black hole formation and evaporation can be described in a unitary manner effectively, through a quantum channel between the exterior and interior of the event horizon. In this way, the paradoxes of information loss and firewall can be resolved effectively. Finally, we show that black hole thermodynamics can be constructed in an ordinary way, by constructing statistical mechanics.