Effective Field Theory of Anisotropic Inflation and Beyond

TL;DR

This paper develops an effective-field-theory framework for anisotropic inflation, capturing symmetry breaking patterns and calculating statistical anisotropy in scalar correlations, advancing theoretical understanding of early universe models.

Contribution

It introduces a novel EFT approach to anisotropic inflation, explicitly incorporating broken symmetries and deriving the effective action for Nambu-Goldstone bosons.

Findings

Derived the effective action for anisotropic inflation models.

Calculated the statistical anisotropy in scalar two-point functions.

Provided examples illustrating the impact of symmetry breaking on inflationary perturbations.

Abstract

We develop an effective-field-theory (EFT) framework for inflation with various symmetry breaking pattern. As a prototype, we formulate anisotropic inflation from the perspective of EFT and construct an effective action of the Nambu-Goldstone bosons for the broken time translation and rotation symmetries. We also calculate the statistical anisotropy in the scalar two-point correlation function for concise examples of the effective action.