English

Soft theorems in curved spacetime

High Energy Physics - Theory 2023-08-15 v3 General Relativity and Quantum Cosmology

Abstract

In this paper, we derive a soft photon theorem in the near horizon region of the Schwarzschild black hole from the Ward identity of the near horizon large gauge transformation. The flat spacetime soft photon theorem can be recovered as a limiting case of the curved spacetime. The soft photons on the horizon are indeed soft electric hairs. This accomplishes the triangle equivalence on the black hole horizon.

Keywords

Cite

@article{arxiv.2206.11564,
  title  = {Soft theorems in curved spacetime},
  author = {Peng Cheng and Pujian Mao},
  journal= {arXiv preprint arXiv:2206.11564},
  year   = {2023}
}

Comments

v3: commutation relation corrected, soft factor corrected, main results unchanged

R2 v1 2026-06-24T12:01:23.753Z