On the EFT of Conformal Symmetry Breaking

TL;DR

This paper develops an effective field theory framework for analyzing conformal symmetry breaking caused by defects, providing a systematic expansion and calculating leading corrections relevant to pseudo-conformal cosmology.

Contribution

It introduces a novel EFT approach for conformal symmetry breaking backgrounds, extending to various defect types and symmetry-breaking scenarios.

Findings

EFT organizes as an inverse VEV expansion.

Leading corrections to fluctuations are computed.

Results applicable to pseudo-conformal universe models.

Abstract

Conformal symmetry can be spontaneously broken due to the presence of a defect or other background, which gives a symmetry-breaking vacuum expectation value (VEV) to some scalar operators. We study the effective field theory of fluctuations around these backgrounds, showing that it organizes as an expansion in powers of the inverse of the VEV, and computing some of the leading corrections. We focus on the case of space-like defects in a four-dimensional Lorentzian theory relevant to the pseudo-conformal universe scenario, although the conclusions extend to other kinds of defects and to the breaking of conformal symmetry to Poincar\'e symmetry.