S-matrix bootstrap for effective field theories: massless pions

Abstract

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

Keywords

• Chiral Lagrangians
• Effective Field Theories
• Scattering Amplitudes