Chiral perturbation theory, dispersion relations and final state interactions in K -> pi pi

TL;DR

This paper reviews methods for analyzing final state interactions in K -> pi pi decays, emphasizing dispersive techniques combined with lattice data, and discusses recent results on quark mass dependence at order p^6 in chiral perturbation theory.

Contribution

It compares different approaches to final state interactions and explores combining dispersive methods with lattice QCD input, highlighting recent theoretical developments.

Findings

Dispersive methods can be integrated with lattice calculations.

Quark mass dependence at order p^6 has been analyzed.

The relevance of these methods for lattice QCD is discussed.

Abstract

We discuss the recent literature on the treatment of final state interactions in K -> pi pi. Various approaches are compared and particular emphasis is given to the possibility of combining dispersive methods with lattice input. Recent results on the dependence of various quantities on the quark masses at order p^6 in the chiral expansion are presented and the relevance for the lattice calculations is discussed.