Massive Nambu-Goldstone Bosons
Abstract
Nicolis and Piazza have recently pointed out the existence of Nambu-Goldstone-like excitations in relativistic systems at finite density, whose gap is exactly determined by the chemical potential and the symmetry algebra. We show that the phenomenon is much more general than anticipated and demonstrate the presence of such modes in a number of systems from (anti)ferromagnets in magnetic field to superfluid phases of quantum chromodynamics. Furthermore, we prove a counting rule for these massive Nambu-Goldstone bosons and construct a low-energy effective Lagrangian that captures their dynamics.
Keywords
Cite
@article{arxiv.1303.1527,
title = {Massive Nambu-Goldstone Bosons},
author = {Haruki Watanabe and Tomáš Brauner and Hitoshi Murayama},
journal= {arXiv preprint arXiv:1303.1527},
year = {2013}
}
Comments
5 pages, REVTeX 4.1; v2: text length reduced upon editor's request, the effective Lagrangian section largely rewritten, other minor changes throughout the text; version accepted to PRL