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arXiv · 1101.1051

Backreaction during inflation: a physical gauge invariant formulation

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

Within a genuinely gauge invariant approach recently developed for the computation of the cosmological backreaction, we study, in a cosmological inflationary context and with respect to various observers, the impact of scalar fluctuations on the space-time dynamics in the long wavelength limit. We stress that such a quantum backreaction effect is evaluated in a truly gauge independent way using a set of effective equations which describe the dynamics of the averaged geometry. In particular we show under what conditions the free falling (geodetic) observers do not experience any scalar-induced backreaction in the effective Hubble rate and fluid equation of state.

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F. Finelli, G. Marozzi, G. P. Vacca, G. Venturi. 2011-02-28. Backreaction during inflation: a physical gauge invariant formulation. https://doi.org/10.1103/physrevlett.106.121304

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