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Is there Unruh radiation?

G. W. Ford·R. F. O'Connell
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Abstract

It is generally accepted that a system undergoing uniform acceleration with respect to zero-temperature vacuum will thermalize at a finite temperature (the so-called Unruh temperature) that is proportional to the acceleration. However, the question of whether or not the system actually radiates is highly controversial. Thus, we are motivated to present an exact calculation using a generalized quantum Langevin equation to describe an oscillator (the detector) moving under a constant force and coupled to a one-dimensional scalar field (scalar electrodynamics). Moreover, our analysis is simplified by using the oscillator as a detector. We show that this system does not radiate despite the fact that it does in fact thermalize at the Unruh temperature. We remark upon a differing opinion expressed regarding a system coupled to the electromagnetic field.

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G. W. Ford, R. F. O'Connell. 2005-09-21. Is there Unruh radiation?. https://doi.org/10.1016/j.physleta.2005.09.068

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