Recent developments in chiral perturbation theory

الأصل · EN

I briefly review the current status of chiral perturbation theory in the meson sector. Emphasis is given on the quest for higher precision. I discuss two examples: one where it is difficult to make a good prediction (Kₗ -> pi⁰ gamma gamma), and where CHPT, even when pushed to higher orders, cannot yield an increase in accuracy. The second one is pi pi scattering where a very sharp prediction can be made by combining CHPT at the two-loop level with dispersion relations