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arXiv · 1201.3163

Fully non-linear equivalence of delta N and covariant formalisms

Teruaki Suyama·Yuki Watanabe·Masahide Yamaguchi
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Abstract

We explicitly show the fully non-linear equivalence of the $δ$N and the covariant formalisms for the superhorizon curvature perturbations, which enables us to safely evaluate the non-Gaussian quantities of the curvature perturbation in either formalism. We also discuss isocurvature perturbations in the covariant formalism and clarify the relation between the fully non-linear evolution of the curvature covector and that of the curvature perturbation for multiple interacting fluids.

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Teruaki Suyama, Yuki Watanabe, Masahide Yamaguchi. 2012-04-05. Fully non-linear equivalence of delta N and covariant formalisms. https://doi.org/10.1103/physrevd.85.083504

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