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arXiv · 2109.04486

Response of an Unruh-DeWitt detector near an extremal black hole

Aindriú Conroy·Peter Taylor
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Abstract

We consider the response of an Unruh-DeWitt detector near an extremal charged black hole, modeling the near-horizon region of this extremal spacetime by the Bertotti-Robinson spacetime. The advantage of employing the Bertotti-Robinson limit is that the two-point functions for a massless scalar field are obtainable in closed form for the field in a number of quantum states of interest. We consider the detector coupled to a massless field in both the Boulware vacuum state and arbitrary thermal states, including the Hartle-Hawking state, and analyse the detector's response for a broad range of trajectories. Particular attention is paid to the thermalization of the detector, the anti-Unruh and anti-Hawking effect.

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Aindriú Conroy, Peter Taylor. 2021-09-09. Response of an Unruh-DeWitt detector near an extremal black hole. https://doi.org/10.1103/physrevd.105.085001

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