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arXiv · 0803.1995

Topological Sigma Models with H-Flux

C. M. Hull·U. Lindstrom·L. Melo dos Santos·R. von Unge·M. Zabzine
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Abstract

We investigate the topological theory obtained by twisting the N=(2,2) supersymmetric nonlinear sigma model with target a bihermitian space with torsion. For the special case in which the two complex structures commute, we show that the action is a Q-exact term plus a quasi-topological term. The quasi-topological term is locally given by a closed two-form which corresponds to a flat gerbe-connection and generalises the usual topological term of the A-model. Exponentiating it gives a Wilson surface, which can be regarded as a generalization of a Wilson line. This makes the quantum theory globally well-defined.

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C. M. Hull, U. Lindstrom, L. Melo dos Santos, R. von Unge, M. Zabzine. 2008-09-09. Topological Sigma Models with H-Flux. https://doi.org/10.1088/1126-6708%2F2008%2F09%2F057

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