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arXiv · 2504.20646

From the Fokker-Planck equation to perturbative QFT's results in de Sitter space

Alexander Kamenshchik·Polina Petriakova
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Abstract

A technique to build perturbative series for the spectator field's correlation functions in de Sitter space through the Fokker-Planck equation is proposed. We derive from the first-order differential equation the iterative integral relation for equal- and multi-time correlation functions. With an appropriate integration, the obtained two-point and four-point correlation functions are in agreement with quantum field theory's ones.

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Alexander Kamenshchik, Polina Petriakova. 2025-04-29. From the Fokker-Planck equation to perturbative QFT's results in de Sitter space. https://doi.org/10.1007/jhep08(2025)063

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