Counting Black Hole Microstates at Future Null Infinity

Vahid Reza Shajiee

doi:10.1016/j.physletb.2025.139381

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arXiv · 2503.03297

Counting Black Hole Microstates at Future Null Infinity

Vahid Reza Shajiee

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Abstract

We propose a black hole microstate counting method based on the canonical quantization of the asymptotic symmetries of a two-dimensional dilaton-gravity system at future null infinity. This dilaton-gravity is obtained from the s-wave reduction of an $N$-dimensional Einstein gravity over a generic asymptotically flat black hole solution. We show that a Cardy-type formula leads to the Bekenstein-Hawking entropy. In this scenario, the quantized bulk degrees of freedom act as a source for the dual field theory operators living at future null infinity that are soft gravitons of the higher dimensional system, up to some gauge fixing.

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Vahid Reza Shajiee. 2025-03-05. Counting Black Hole Microstates at Future Null Infinity. https://doi.org/10.1016/j.physletb.2025.139381

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