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arXiv · 1103.4799

Spontaneously broken ground states of the U(n)_L x U(n)_R linear sigma model at large n

G. Fejos·A. Patkos
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Abstract

Symmetry breaking patterns of the U(n)_L x U(n)_R symmetric meson model are investigated in a formulation involving three auxiliary composite fields. The effective potential is constructed at leading order in the 1/n expansion for a condensate belonging to the center of the U(n) group. A wide region is found in the coupling space where in addition to the condensate proportional to the unit matrix, also metastable minima exist, in which a further breakdown of the diagonal U_V(n) symmetry to U_V(n-1) is realized. Application of a moderate external field conjugate to this component of the order parameter changes this state into the true ground state of the system.

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G. Fejos, A. Patkos. 2011-08-03. Spontaneously broken ground states of the U(n)_L x U(n)_R linear sigma model at large n. https://doi.org/10.1103/physrevd.84.036001

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