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arXiv · hep-ph/9807318

Three-Flavor QCD at High Density: Color Flavor Locking and Chiral Symmetry Breaking

Krishna Rajagopal
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Abstract

We propose a symmetry breaking scheme for QCD with three massless quarks at high baryon density wherein the color and flavor SU(3)_{color}xSU(3)_{L}xSU(3)_{R} symmetries are broken down to the diagonal subgroup SU(3)_{color+L+R} by the formation of a condensate of quark Cooper pairs. We discuss general properties that follow from this hypothesis, including the existence of gaps for quark and gluon excitations, the existence of Nambu-Goldstone bosons which are excitations of the diquark condensate, and the existence of a modified electromagnetic gauge interaction which is unbroken and which assigns integral charge to the elementary excitations. We present mean-field results for a Hamiltonian in which the interaction between quarks is modelled by that induced by single-gluon exchange. We find gaps of order 10-100 MeV for plausible values of the coupling. We discuss the effects of nonzero temperature, nonzero quark masses and instanton-induced interactions on our results.

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Krishna Rajagopal. 1998-07-09. Three-Flavor QCD at High Density: Color Flavor Locking and Chiral Symmetry Breaking. https://doi.org/10.1016/s0375-9474(98)00495-3

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