A Diagrammatic Approach to Scalar Field Correlators during Inflation

G. Petri

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arXiv · 0810.3330

A Diagrammatic Approach to Scalar Field Correlators during Inflation

G. Petri

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Abstract

We consider a self-interacting scalar field in a de Sitter background and deal with the associated infrared divergences in a purely diagrammatic way using the in-in formalism. In the particular case of a large N O(N) invariant scalar field theory with quartic self-interactions we recover the result that the connected four-point correlation function, which is a signal of non-Gaussianity, is non-perturbatively enhanced with respect to its tree-level value.

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G. Petri. 2008-10-21. A Diagrammatic Approach to Scalar Field Correlators during Inflation. https://arxiv.org/abs/0810.3330

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