Nambu-Goldstone dynamics and generalized coherent-state functional integrals
Abstract
The present paper gives a new method of attack on the Nambu-Goldstone dynamics in spontaneously broken theories. Since the target space of the Nambu-Goldstone fields is a group coset space, their effective quantum dynamics can be naturally phrased in terms of generalized coherent-state functional integrals. As an explicit example of this line of reasoning we construct a low-energy effective Lagrangian for the Heisenberg ferromagnet in broken phase. The leading field configuration in the WKB approximation leads to the Landau-Lifshitz equation for quantum ferromagnet. The corresponding linearized equations allow to identify the Nambu-Goldstone boson with ferromagnetic magnon.
Keywords
Cite
@article{arxiv.1111.3228,
title = {Nambu-Goldstone dynamics and generalized coherent-state functional integrals},
author = {Massimo Blasone and Petr Jizba},
journal= {arXiv preprint arXiv:1111.3228},
year = {2012}
}
Comments
17 pages, IOP LaTeX, revised version with minor changes, accepted to J. Phys. A: Math. Theor