Spontaneous symmetry breaking in the linear sigma model at finite chemical potential: One-loop corrections
Abstract
We investigate spontaneous symmetry breaking within the linear sigma model with the SU(2)xU(1) internal symmetry at finite chemical potential, which was suggested as a model for kaon condensation in the CFL phase of dense quark matter. One-loop corrections to the scalar field effective potential as well as its propagator are calculated. Particular attention is paid to the type-II Goldstone boson that appears in the Bose--Einstein condensed phase. Furthermore, we show that the type-I Goldstone boson -- the superfluid phonon -- is allowed to decay due to the nonlinearity of its dispersion relation at high momentum, and determine its decay width.
Keywords
Cite
@article{arxiv.hep-ph/0607102,
title = {Spontaneous symmetry breaking in the linear sigma model at finite chemical potential: One-loop corrections},
author = {Tomas Brauner},
journal= {arXiv preprint arXiv:hep-ph/0607102},
year = {2008}
}
Comments
13 pages, REVTeX4, 37 eps figures; v2: substantial error in Sec. IV corrected, references added, other minor corrections; version to appear in Phys. Rev. D