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arXiv · 1011.3336

On the Unruh effect in de Sitter space

R. Casadio·S. Chiodini·A. Orlandi·G. Acquaviva·R. Di Criscienzo·L. Vanzo
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Abstract

We give an interpretation of the temperature in de Sitter universe in terms of a dynamical Unruh effect associated with the Hubble sphere. As with the quantum noise perceived by a uniformly accelerated observer in static space-times, observers endowed with a proper motion can in principle detect the effect. In particular, we study a "Kodama observer" as a two-field Unruh detector for which we show the effect is approximately thermal. We also estimate the back-reaction of the emitted radiation and find trajectories associated with the Kodama vector fields are stable.

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R. Casadio, S. Chiodini, A. Orlandi, G. Acquaviva, R. Di Criscienzo, L. Vanzo. 2011-09-12. On the Unruh effect in de Sitter space. https://doi.org/10.1142/s0217732311036516

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