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arXiv · 1409.7964

The Weyl tensor correlator in cosmological spacetimes

Markus B. Fröb
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Abstract

We give a general expression for the Weyl tensor two-point function in a general Friedmann-Lemaître-Robertson-Walker spacetime. We work in reduced phase space for the perturbations, i.e., quantize only the dynamical degrees of freedom without adding any gauge-fixing term. The general formula is illustrated by a calculation in slow-roll single-field inflation to first order in the slow-roll parameters $ε$ and $δ$, and the result is shown to have the correct de Sitter limit as $ε, δ\to 0$. Furthermore, it is seen that the Weyl tensor correlation function does not suffer from infrared divergences, unlike the two-point functions of the metric and scalar field perturbations. Lastly, we show how to recover the usual tensor power spectrum from the Weyl tensor correlation function.

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Markus B. Fröb. 2014-12-08. The Weyl tensor correlator in cosmological spacetimes. https://doi.org/10.1088/1475-7516%2F2014%2F12%2F010

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