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arXiv · 2005.02504

Renormalization group inspired autonomous equations for secular effects in de Sitter space

Alexander Yu. Kamenshchik·Tereza Vardanyan
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Abstract

We develop a method for treating a series of secularly growing terms obtained from quantum perturbative calculations: autonomous first-order differential equations are constructed such that they reproduce this series to the given order. The exact solutions of these equations are free of secular terms and approach a finite limit at late times. This technique is illustrated for the well-known problem of secular growth of correlation functions of a massless scalar field with a quartic self-interaction in de Sitter space. For the expectation value of the product of two fields at coinciding space-time points we obtain a finite late-time result that is very close to the one following from Starobinsky's stochastic approach.

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Alexander Yu. Kamenshchik, Tereza Vardanyan. 2020-05-05. Renormalization group inspired autonomous equations for secular effects in de Sitter space. https://doi.org/10.1103/physrevd.102.065010

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