Effective Field Theory for Large Scale Structure

Mikhail M. Ivanov

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arXiv · 2212.08488

Effective Field Theory for Large Scale Structure

Mikhail M. Ivanov

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Abstract

This chapter is a non-expert introduction to the effective field theory of large scale structure. First, we give a detailed pedagogical explanation of why previous attempts to build non-linear cosmological perturbation theory failed. After that we introduce the description of dark matter as an effective non-ideal fluid and show how it corrects the shortcomings of the previous approaches. Finally, we develop a formulation of the effective field theory of large-scale structure from a nonequilibrium field theory perspective, called time-sliced perturbation theory. We show how this framework can be used for a consistent renormalization of cosmological correlation functions and a systematic resummation of large infrared effects relevant for the baryon acoustic oscillations.

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Mikhail M. Ivanov. 2022-12-16. Effective Field Theory for Large Scale Structure. https://arxiv.org/abs/2212.08488

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