Chiral perturbation theory, dispersion relations and final state interactions in K → ππ

Abstract

We discuss the recent literature on the treatment of final state interactions in K → ππ. 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.