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arXiv · 0707.3919

A graviton propagator for inflation

Tomas Janssen·Tomislav Prokopec
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Abstract

We construct the scalar and graviton propagator in quasi de Sitter space up to first order in the slow roll parameter $ε\equiv -\dot{H}/H^2$. After a rescaling, the propagators are similar to those in de Sitter space with an $ε$ correction to the effective mass. The limit $ε\to 0$ corresponds to the E(3) vacuum that breaks de Sitter symmetry, but does not break spatial isotropy and homogeneity. The new propagators allow for a self-consistent, dynamical study of quantum back-reaction effects during inflation.

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Tomas Janssen, Tomislav Prokopec. 2007-07-26. A graviton propagator for inflation. https://doi.org/10.1088/0264-9381%2F25%2F5%2F055007

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