A New Approach to Black Hole Microstates

TL;DR

This paper proposes a novel boundary action derived from a first order gravitational formulation that could explain black hole microstates and entropy across various dimensions.

Contribution

It introduces a new boundary action within the Goldberg formalism that captures microscopic degrees of freedom at black hole horizons.

Findings

Boundary action encodes horizon microstates

Potential explanation for black hole entropy

Applicable to multiple spacetime dimensions

Abstract

If one encodes the gravitational degrees of freedom in an orthonormal frame field there is a very natural first order action one can write down (which in four dimensions is known as the Goldberg action). In this essay we will show that this action contains a boundary action for certain microscopic degrees of freedom living at the horizon of a black hole, and argue that these degrees of freedom hold great promise for explaining the microstates responsible for black hole entropy, in any number of spacetime dimensions. This approach faces many interesting challenges, both technical and conceptual.