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  • Open Access

Double Copy Root of Hawking Thermality

John Joseph M. Carrasco and Yaxi Chen

  • Amplitudes and Insights Group, Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA and Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Northwestern University, 1800 Sherman Ave, Evanston, Illinois 60201, USA

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Phys. Rev. Lett. 136, 081604 – Published 27 February, 2026

DOI: https://doi.org/10.1103/6gfs-kxbt

Abstract

The Hawking radiation spectrum from a collapsing null shell can be derived via the double copy of a simpler gauge theory calculation. Analyzing the non-Abelian Yang-Mills root of this process, we demonstrate that the radiation spectrum is thermal in the color charge eigenvalue λ, not energy. Considering the SU(Nc) gauge theory in the large Nc limit, we find the differential spectrum dN/dλ is a product of the gravitationally familiar Planck-like factor and the color phase space density, modeled here as the Wigner semicircle from random matrix theory. This reveals that apparent energy thermality in gravity is the direct dual of charge thermality in its underlying non-abelian gauge theory.

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See Also

Hawking Radiation from the Double Copy

Anton Ilderton, William Lindved, and Karthik Rajeev
Phys. Rev. Lett. 136, 081603 (2026)

Article Text

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Phys. Rev. Lett. 136, 081604– Published 27 February, 2026
  • Received 5 November 2025
  • Revised 17 December 2025
  • Accepted 21 January 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.

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