Entropy/information flux in Hawking radiation
Abstract
Blackbody radiation contains (on average) an entropy of 3.9\pm2.5 bits per photon. If the emission process is unitary, then this entropy is exactly compensated by "hidden information" in the correlations. We extend this argument to the Hawking radiation from GR black holes, demonstrating that the assumption of unitarity leads to a perfectly reasonable entropy/information budget. The key technical aspect of our calculation is a variant of the "average subsystem" approach developed by Page, which we extend beyond bipartite pure systems, to a tripartite pure system that considers the influence of the environment.
Keywords
Cite
@article{arxiv.1512.01890,
title = {Entropy/information flux in Hawking radiation},
author = {Ana Alonso-Serrano and Matt Visser},
journal= {arXiv preprint arXiv:1512.01890},
year = {2025}
}
Comments
V1: 32 pages, 6 figures; V2: considerable additional discussion added; 8 additional references; no change in physics conclusions; V3: reformatted, argument streamlined, now just over 8 pages. This version closely matches the published version. Some technical discussion spun-off into 1707.09755 [quant-ph]; PRA96 (2017) 052302