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arXiv · hep-th/0103242

Branched Coverings and Interacting Matrix Strings in Two Dimensions

M. Billo'·A. D'Adda·P. Provero
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Abstract

We construct the lattice gauge theory of the group G_N, the semidirect product of the permutation group S_N with U(1)^N, on an arbitrary Riemann surface. This theory describes the branched coverings of a two-dimensional target surface by strings carrying a U(1) gauge field on the world sheet. These are the non-supersymmetric Matrix Strings that arise in the unitary gauge quantization of a generalized two-dimensional Yang-Mills theory. By classifying the irreducible representations of G_N, we give the most general formulation of the lattice gauge theory of G_N, which includes arbitrary branching points on the world sheet and describes the splitting and joining of strings.

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M. Billo', A. D'Adda, P. Provero. 2001-03-29. Branched Coverings and Interacting Matrix Strings in Two Dimensions. https://doi.org/10.1016/s0550-3213(01)00384-4

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