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arXiv · 1208.3165

Unruh-DeWitt detector on the BTZ black hole

Lee Hodgkinson·Jorma Louko
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Abstract

We examine an Unruh-DeWitt particle detector coupled to a scalar field in three-dimensional curved spacetime, within first-order perturbation theory. We first obtain a causal and manifestly regular expression for the instantaneous transition rate in an arbitrary Hadamard state. We then specialise to the Ba\~nados-Teitelboim-Zanelli black hole and to a massless conformally coupled field in the Hartle-Hawking vacuum. A co-rotating detector responds thermally in the expected local Hawking temperature, while a freely-falling detector shows no evidence of thermality in regimes that we are able to probe, not even far from the horizon. The boundary condition at the asymptotically anti-de Sitter infinity has a significant effect on the transition rate.

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Lee Hodgkinson, Jorma Louko. 2012-08-15. Unruh-DeWitt detector on the BTZ black hole. https://arxiv.org/abs/1208.3165

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