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arXiv · hep-lat/0211018

Lattice gauge theory with baryons at strong coupling

Barak Bringoltz·Benjamin Svetitsky
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Abstract

We study the effective Hamiltonian for strong-coupling lattice QCD in the case of non-zero baryon density. In leading order the effective Hamiltonian is a generalized antiferromagnet. For naive fermions, the symmetry is U(4N_f) and the spins belong to a representation that depends on the local baryon number. Next-nearest-neighbor (nnn) terms in the Hamiltonian break the symmetry to U(N_f) x U(N_f). We transform the quantum problem to a Euclidean sigma model which we analyze in a 1/N_c expansion. In the vacuum sector we recover spontaneous breaking of chiral symmetry for the nearest-neighbor and nnn theories. For non-zero baryon density we study the nearest-neighbor theory only, and show that the pattern of spontaneous symmetry breaking depends on the baryon density.

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Barak Bringoltz, Benjamin Svetitsky. 2002-11-13. Lattice gauge theory with baryons at strong coupling. https://doi.org/10.1103/physrevd.68.034501

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