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arXiv · 1706.08978

Over the horizon: distinguishing the Schwarzschild spacetime and the $\mathbb{RP}^3$ spacetime using an Unruh-DeWitt detector

Keith K. Ng·Robert B. Mann·Eduardo Martin-Martinez
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Abstract

We show that a particle detector can distinguish the $\mathbb{RP}^3$ geon from the Schwarzschild black hole, even though they differ only by a topological identification beyond the event horizon. This shows that the detector can read out information about the non-local structure even when separated from the non-locality by an event horizon. Our analysis of the dependence of the transition on the detector gap is novel, and in principle presents an interesting observational signal.

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Keith K. Ng, Robert B. Mann, Eduardo Martin-Martinez. 2017-06-27. Over the horizon: distinguishing the Schwarzschild spacetime and the $\mathbb{RP}^3$ spacetime using an Unruh-DeWitt detector. https://doi.org/10.1103/physrevd.96.085004

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