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arXiv · 1401.6912

Spacetime correlators of perturbations in slow-roll de Sitter inflation

Adrian del Rio·Jose Navarro-Salas
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Abstract

Two-point correlators and self-correlators of primordial perturbations in quasi-de Sitter spacetime backgrounds are considered. For large separations two-point correlators exhibit nearly scale invariance, while for short distances self-correlators need standard renormalization. We study the deformation of two-point correlators to smoothly match the self-correlators at coincidence. The corresponding angular power spectrum is evaluated in the Sachs-Wolfe regime of low multipoles. Scale invariance is maintained, but the amplitude of $C_{\ell}$ could change in a non-trivial way.

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Adrian del Rio, Jose Navarro-Salas. 2014-04-10. Spacetime correlators of perturbations in slow-roll de Sitter inflation. https://doi.org/10.1103/physrevd.89.084037

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