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Recent developments in chiral perturbation theory

Gilberto Colangelo
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Abstract

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 (K_L -> pi^0 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

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Gilberto Colangelo. 2000-11-02. Recent developments in chiral perturbation theory. https://arxiv.org/abs/hep-ph/0011025

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