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B836A988-C245-4955-8871-EA3BC9696421

# Testing the black hole area law with Event Horizon Telescope

Deng Wang
arXiv:2207.00846

Submitted on 2 July 2022

## Abstract

Hawking's black hole area theorem can be tested by monitoring the evolution of a single black hole over time. Using current imaging observations of two supermassive black holes M87* and Sgr A* from the Event Horizon Telescope (EHT), we find their horizon area variation fractions are consistent with the prediction of the black hole area law at the $1\phantom{\rule{0.167em}{0ex}}\sigma$ confidence level. We point out that whether the black hole area law is valid or not could be determined by future high precision EHT observations of Sgr A*.

## Preprint

Comment: 4 pages, 4 figs

Subjects: General Relativity and Quantum Cosmology; Astrophysics - Astrophysics of Galaxies; Astrophysics - High Energy Astrophysical Phenomena