S-matrix Bootstrap for Effective Field Theories: Massless Pions

TL;DR

This paper demonstrates how the numerical S-matrix bootstrap can be used to derive non-perturbative bounds on effective field theories, specifically for the low-energy dynamics of massless pions, showcasing its potential in higher dimensions.

Contribution

It applies the numerical S-matrix bootstrap to constrain Wilson coefficients in the chiral Lagrangian for massless pions, marking a novel non-perturbative approach in more than two dimensions.

Findings

Bounded the two leading Wilson coefficients of the chiral Lagrangian.

Proved the feasibility of using the S-matrix bootstrap for EFTs in higher dimensions.

Provided a proof of concept for non-perturbative bounds in EFTs.

Abstract

We use the numerical S-matrix bootstrap method to obtain bounds on the two leading Wilson coefficients of the chiral lagrangian controlling the low-energy dynamics of massless pions thus providing a proof of concept that the numerical S-matrix bootstrap can be used to derive non-perturbative bounds on EFTs in more than two spacetime dimensions.