Covariant Anomalies, Horizons and Hawking Radiation

TL;DR

This paper demonstrates that Hawking radiation can be derived solely from covariant anomalies near black hole horizons, emphasizing the universality of the anomaly-based approach in black hole thermodynamics.

Contribution

It shows that covariant anomalies alone are sufficient to derive Hawking radiation, simplifying previous methods and highlighting their fundamental role.

Findings

Hawking flux can be obtained from covariant anomalies alone

Covariant anomalies are the key input for Hawking radiation derivation

Method can be extended to compute entropy and temperature

Abstract

Hawking radiation is obtained from anomalies resulting from a breaking of diffeomorphism symmetry near the event horizon of a black hole. Such anomalies, manifested as a nonconservation of the energy momentum tensor, occur in two different forms -- covariant and consistent. The crucial role of covariant anomalies near the horizon is revealed since this is the {\it only} input required to obtain the Hawking flux, thereby highlighting the universality of this effect. A brief description to apply this method to obtain thermodynamic entities like entropy or temperature is provided.