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Energy-Momentum Tensor of Cosmological Fluctuations during Inflation

F. Finelli·G. Marozzi·G. P. Vacca·G. Venturi
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Abstract

We study the renormalized energy-momentum tensor (EMT) of cosmological scalar fluctuations during the slow-rollover regime for chaotic inflation with a quadratic potential and find that it is characterized by a negative energy density which grows during slow-rollover. We also approach the back-reaction problem as a second-order calculation in perturbation theory finding no evidence that the back-reaction of cosmological fluctuations is a gauge artifact. In agreement with the results on the EMT, the average expansion rate is decreased by the back-reaction of cosmological fluctuations.

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F. Finelli, G. Marozzi, G. P. Vacca, G. Venturi. 2004-03-29. Energy-Momentum Tensor of Cosmological Fluctuations during Inflation. https://doi.org/10.1103/physrevd.69.123508

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