Chiral Perturbation Theory and Mesons

Understand

The talk contains a short introduction to mesonic Chiral Perturbation Theory (ChPT).

• In addition four disparate areas where some progress has been made in recent years are discussed.
• These are the last fit of the order $p^4$ low-energy-constants $L_i^r$ to data, hard pion ChPT, the recent two-loop work on EFT for QCD like theories and the high order leading logarithm calculations in the massive $O(N)$ nonlinear sigma model.