https://doi.org/10.1140/epjp/s13360-023-04201-z
Regular Article
Quantum hair in electrodynamics and gravity
1
Department of Physics and Astronomy, University of Sussex, BN1 9QH, Brighton, UK
2
Department of Physics and Astronomy, Michigan State University, 48823, East Lansing, MI, USA
Received:
10
May
2023
Accepted:
17
June
2023
Published online:
5
July
2023
We demonstrate the existence of quantum hair in electrodynamics and gravity using effective action techniques. In the case of electrodynamics we use the Euler–Heisenberg effective action, while in the case of quantum gravity we use the unique effective action. We give a general formulation of these effects which applies to both theories and discuss analogies and differences between them. Furthermore, we present a QED analog to black hole evaporation. Spontaneous pair production in the external field of a ball of charge is analogous to Hawking radiation from black holes. Assuming spherical symmetry, the Gauss law prevents the external field from depending on the density profile of the ball. Quantum corrections violate these expectations, showing that quantum radiation can encode classically forbidden information about the source.
© The Author(s) 2023
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