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arXiv · 2505.07722

Effective Field Theory Description of Hawking Radiation

David A. Lowe·Larus Thorlacius
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Abstract

A study is made of Hawking radiation from four-dimensional black holes using effective field theory methods. The trace anomaly for the stress tensor in a general curved spacetime background is reproduced using Riegert's action. The semiclassical stress tensor is evaluated in a Schwarzschild background taking a time-independent limit for the quantum state. Imposing physical boundary conditions on an initial Cauchy surface leads to a unique state, analogous to the Unruh state with a vanishing ingoing flux and a finite outgoing flux. In particular, there is no sign of quantum hair arising from this nonlocal effective action.

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David A. Lowe, Larus Thorlacius. 2025-05-12. Effective Field Theory Description of Hawking Radiation. https://arxiv.org/abs/2505.07722

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