Apparent Fine Tunings for Field Theories with Broken Space-Time Symmetries

TL;DR

This paper introduces a class of effective field theories with small Wilson coefficients and broken space-time symmetries, exhibiting unique RG flows and vacuum energy relaxation, offering new insights into symmetry breaking and hierarchy problems.

Contribution

It presents a novel class of theories with bounded target spaces and vacua breaking space-time symmetries, featuring unusual RG flows and small vacuum energy, expanding understanding of symmetry breaking mechanisms.

Findings

Hierarchically small Wilson coefficients without fine-tuning.

Unusual RG flows where irrelevant operators become relevant.

Vacuum energy relaxes to a small value compared to UV cutoff.

Abstract

We exhibit a class of effective field theories that have hierarchically small Wilson coefficients for operators that are not protected by symmetries but are not finely tuned. These theories possess bounded target spaces and vacua that break space-time symmetries. We give a physical interpretation of these theories as generalized solids with open boundary conditions. We show that these theories realize unusual RG flows where higher dimensional (seemingly irrelevant) operators become relevant even at weak coupling. Finally, we present an example of a field theory whose vacuum energy relaxes to a hierarchically small value compared to the UV cut-off.