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arXiv · hep-th/0112043

DLCQ strings and branched covers of torii

Gordon W. Semenoff
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Abstract

In this lecture I will review some results about the discrete light-cone quantization (DLCQ) of strings and some connections of the results with matrix string theory. I will review arguments which show that, in the path integral representation of the thermal free energy of a string, the compactifications which are necessary to obtain discrete light-cone quantization constrains the integral over all Riemann surfaces of a given genus to the set of those Riemann surfaces which are branched covers of a particular torus. I then review an explicit check of this result at genus 1. I discuss the intriguing suggestion that these branched covers of a torus are related to those which are found in a certain limit of the matrix string model

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Gordon W. Semenoff. 2001-12-06. DLCQ strings and branched covers of torii. https://doi.org/10.1016/s0920-5632(02)01311-7

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