Hawking radiation, W-infinity algebra and trace anomalies

TL;DR

This paper explores the connection between Hawking radiation, W-infinity algebra, and trace anomalies, demonstrating that fluxes of chiral currents form a W-infinity algebra and analyzing trace anomalies in two-dimensional models.

Contribution

It introduces a novel application of the trace anomaly method to Hawking radiation moments and constructs covariant chiral currents, showing their invariance up to order 6.

Findings

Hawking radiation moments are explained by W-infinity algebra fluxes.

Covariant currents up to order 6 are unaffected by trace anomalies.

No trace anomalies exist for the fourth order current in two dimensions.

Abstract

We apply the "trace anomaly method" to the calculation of moments of the Hawking radiation of a Schwarzschild black hole. We show that they can be explained as the fluxes of chiral currents forming a W-infinity algebra. Then we construct the covariant version of these currents and verify that up to order 6 they are not affected by any trace anomaly. Using cohomological methods we show that actually, for the fourth order current, no trace anomalies can exist. The results reported here are strictly valid in two dimensions.