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arXiv · 1612.07259

The Skyrme model and chiral perturbation theory

Derek Harland
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Abstract

A lagrangian which describes interactions between a soliton and a background field is derived for sigma models whose target is a symmetric space. The background field modifies the usual moduli space approximation to soliton dynamics in two ways: by introducing a potential energy, and by inducing a Kaluza-Klein metric on the moduli space. In the particular case of the Skyrme model, this lagrangian is quantised and shown to agree with the leading pion-nucleon term in the chiral effective lagrangian, which is widely used in theoretical nuclear physics. Thus chiral perturbation theory could be considered a low energy limit of the Skyrme model.

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Derek Harland. 2016-12-21. The Skyrme model and chiral perturbation theory. https://arxiv.org/abs/1612.07259

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