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arXiv · hep-th/9908142

String Theory and Noncommutative Geometry

Nathan Seiberg·Edward Witten
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Abstract

We extend earlier ideas about the appearance of noncommutative geometry in string theory with a nonzero B-field. We identify a limit in which the entire string dynamics is described by a minimally coupled (supersymmetric) gauge theory on a noncommutative space, and discuss the corrections away from this limit. Our analysis leads us to an equivalence between ordinary gauge fields and noncommutative gauge fields, which is realized by a change of variables that can be described explicitly. This change of variables is checked by comparing the ordinary Dirac-Born-Infeld theory with its noncommutative counterpart. We obtain a new perspective on noncommutative gauge theory on a torus, its T-duality, and Morita equivalence. We also discuss the D0/D4 system, the relation to M-theory in DLCQ, and a possible noncommutative version of the six-dimensional (2,0) theory.

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Nathan Seiberg, Edward Witten. 1999-11-30. String Theory and Noncommutative Geometry. https://doi.org/10.1088/1126-6708%2F1999%2F09%2F032

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