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arXiv · hep-th/0110287

The geometry of N=4 twisted string

Stefano Bellucci·Alexei Deriglazov·Anton Galajinsky
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Abstract

We compare N=2 string and N=4 topological string within the framework of the sigma model approach. Being classically equivalent on a flat background, the theories are shown to lead to different geometries when put in a curved space. In contrast to the well studied Kaehler geometry characterising the former case, in the latter case a manifold has to admit a covariantly constant holomorphic two-form in order to support an N=4 twisted supersymmetry. This restricts the holonomy group to be a subgroup of SU(1,1) and leads to a Ricci--flat manifold. We speculate that, the N=4 topological formalism is an appropriate framework to smooth down ultraviolet divergences intrinsic to the N=2 theory.

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Stefano Bellucci, Alexei Deriglazov, Anton Galajinsky. 2001-10-31. The geometry of N=4 twisted string. https://doi.org/10.1103/physrevd.65.104026

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