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Universal Correction to the Inflationary Vacuum

Brian Greene·Maulik Parikh·Jan Pieter van der Schaar
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Abstract

The Bunch-Davies state appears precisely thermal to a free-falling observer in de Sitter space. However, precise thermality is unphysical because it violates energy conservation. Instead, the true spectrum must take a certain different form, with the Boltzmann factor $\exp(-βω_k)$ replaced by $\exp(ΔS)$, where $S$ is the entropy of the de Sitter horizon. The deviation from precise thermality can be regarded as an explicitly calculable correction to the Bunch-Davies state. This correction is mandatory in that it relies only on energy conservation. The modified Bunch-Davies state leads, in turn, to an ${\cal O} (H/M_p)^2$ modification of the primordial power spectrum of inflationary perturbations, which we determine.

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Brian Greene, Maulik Parikh, Jan Pieter van der Schaar. 2006-02-24. Universal Correction to the Inflationary Vacuum. https://doi.org/10.1088/1126-6708%2F2006%2F04%2F057

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