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arXiv · 1410.2612

Feeling de Sitter

Andreas Albrecht·R. Holman·Benoit J. Richard
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Abstract

We address the following question: To what extent can a quantum field tell if it has been placed in de Sitter space? Our approach is to use the techniques of non-equilibrium quantum field theory to compute the time evolution of a state which starts off in flat space for (conformal) times $η<η_0$, and then evolves in a de Sitter background turned on instantaneously at $η=η_0$. We find that the answer depends on what quantities one examines. We study a range of them, all based on two-point correlation functions, and analyze which ones approach the standard Bunch-Davies values over time. The outcome of this analysis suggests that the nature of the equilibration process in this system is similar to that in more familiar systems.

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Andreas Albrecht, R. Holman, Benoit J. Richard. 2015-01-14. Feeling de Sitter. https://doi.org/10.1103/physrevd.91.043517

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