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arXiv · 1207.7089

Kermions: quantization of fermions on Kerr space-time

Marc Casals·Sam R. Dolan·Brien C. Nolan·Adrian C. Ottewill·Elizabeth Winstanley
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Abstract

We study a quantum fermion field on a background non-extremal Kerr black hole. We discuss the definition of the standard black hole quantum states (Boulware, Unruh and Hartle-Hawking), focussing particularly on the differences between fermionic and bosonic quantum field theory. Since all fermion modes (both particle and anti-particle) have positive norm, there is much greater flexibility in how quantum states are defined compared with the bosonic case. In particular, we are able to define a candidate `Boulware'-like state, empty at both past and future null infinity; and a candidate `Hartle-Hawking'-like equilibrium state, representing a thermal bath of fermions surrounding the black hole. Neither of these states have analogues for bosons on a non-extremal Kerr black hole and both have physically attractive regularity properties. We also define a number of other quantum states, numerically compute differences in expectation values of the fermion current and stress-energy tensor between two states, and discuss their physical properties.

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Marc Casals, Sam R. Dolan, Brien C. Nolan, Adrian C. Ottewill, Elizabeth Winstanley. 2013-06-28. Kermions: quantization of fermions on Kerr space-time. https://doi.org/10.1103/physrevd.87.064027

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