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arXiv · 2109.13260

A Little Excitement Across the Horizon

Keith K. Ng·Chen Zhang·Jorma Louko·Robert B. Mann
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Abstract

We analyse numerically the transitions in an Unruh-DeWitt detector, coupled linearly to a massless scalar field, in radial infall in (3+1)-dimensional Schwarzschild spacetime. In the Hartle-Hawking and Unruh states, the transition probability attains a small local extremum near the horizon-crossing and is then moderately enhanced on approaching the singularity. In the Boulware state, the transition probability drops on approaching the horizon. The unexpected near-horizon extremum arises numerically from angular momentum superpositions, with a deeper physical explanation to be found.

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Keith K. Ng, Chen Zhang, Jorma Louko, Robert B. Mann. 2021-09-27. A Little Excitement Across the Horizon. https://doi.org/10.1088/1367-2630%2Fac9547

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