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arXiv · hep-ph/9311274

On the Foundations of Chiral Perturbation Theory

H. Leutwyler
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Abstract

The properties of the effective field theory relevant for the low energy structure generated by the Goldstone bosons of a spontaneously broken symmetry are reexamined. It is shown that anomaly free, Lorentz invariant theories are characterized by a gauge invariant effective Lagrangian, to all orders of the low energy expansion. The paper includes a discussion of anomalies and approximate symmetries, but does not cover nonrelativistic effective theories.

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H. Leutwyler. 1993-11-11. On the Foundations of Chiral Perturbation Theory. https://doi.org/10.1006/aphy.1994.1094

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