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arXiv · hep-lat/9301014

SU(N) Quantum Antiferromagnets and the Phase Structure of QED in the Strong Coupling Limit

M. C. Diamantini E. Langmann G. W. Semenoff P. Sodano
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Abstract

We examine the strong coupling limit of both compact and non compact QED on a lattice with staggered fermions. We show that every SU(N) antiferromagnet with spins in a particular fundamental representation of the SU(N) Lie Algebra and with nearest neighbor couplings on a bipartite lattice is exactly equivalent to the infinite coupling limit of lattice QED with the numbers of flavors of electrons related to N and the dimension of spacetime D+1. We find that,for both compact and noncompact QED,when N is odd the ground state of the strong coupling limit breaks chiral symmetry in any dimensions and for any N and the condensate is an isoscalar mass operator. When N is even,chiral symmetry is broken if D is bigger or equal to 2 and N is small enough and the order parameter is an isovector mass operator. We also find the exact ground state of the lattice Coulomb gas as well as a variety of related lattice statistical systems with long ranged interactions.

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M. C. Diamantini E. Langmann G. W. Semenoff P. Sodano. 1993-01-21. SU(N) Quantum Antiferromagnets and the Phase Structure of QED in the Strong Coupling Limit. https://doi.org/10.1016/0550-3213(93)90003-8

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