Relations at Order p 6 in Chiral Perturbation Theory

We report on a search of relations valid at order p 6 in Chiral Perturbation Theory. We have found relations between ππ, πK scattering, Kℓ4 decays, masses and decay constants and scalar and vector form factors. In this paper we give the relations and a first numerical check of them. PACS: 12.39.Fe Chiral Lagrangians, 11.30.Rd Chiral symmetries, 14.40.Aq π, K, and η Chiral Perturbation Theory (ChPT) [1, 2, 3] is the effective field theory for the strong interaction at low energies. Some recent reviews are [4, 5, 6]. In the mesonic sector many calculations have now been performed to two-loop or next-to-next-to-leading order (NNLO), see the review [5]. Since in an effective field theory like ChPT there appear