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Excited by a quantum field: Does shape matter?

Jorma Louko·Alejandro Satz
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Abstract

The instantaneous transition rate of an arbitrarily accelerated Unruh-DeWitt particle detector on four-dimensional Minkowski space is ill defined without regularisation. We show that Schlicht's regularisation as the zero-size limit of a Lorentz-function spatial profile yields a manifestly well-defined transition rate with physically reasonable asymptotic properties. In the special case of stationary trajectories, including uniform acceleration, we recover the results that have been previously obtained by a regularisation that relies on the stationarity. Finally, we discuss evidence for the conjecture that the zero-size limit of the transition rate is independent of the detector profile.

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Jorma Louko, Alejandro Satz. 2006-09-17. Excited by a quantum field: Does shape matter?. https://doi.org/10.1088/1742-6596%2F68%2F1%2F012014

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