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arXiv · hep-th/0102099

Universal hypermultiplet metrics

Sergei V. Ketov
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Abstract

Some instanton corrections to the universal hypermultiplet moduli space metric of the type-IIA string theory compactified on a Calabi-Yau threefold arise due to multiple wrapping of BPS membranes and fivebranes around certain cycles of Calabi-Yau. The classical universal hypermultipet metric is locally equivalent to the Bergmann metric of the symmetric quaternionic space SU(2,1)/U(2), whereas its generic quaternionic deformations are governed by the integrable SU(infinity) Toda equation. We calculate the exact (non-perturbative) UH metrics in the special cases of (i) the D-instantons (the wrapped D2-branes) in the absence of fivebranes, and (ii) the fivebrane instantons with vanishing charges, in the absence of D-instantons. The solutions of the first type preserve the U(1)xU(1) classical symmetry, while they can be interpreted as the gravitational dressing of the hyper-K"ahler D-instanton solutions. The second type solution preserves the non-abelian SU(2) classical symmetry, while it can be interpreted as a gradient flow in the universal hypermultiplet moduli space.

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Sergei V. Ketov. 2001-02-16. Universal hypermultiplet metrics. https://doi.org/10.1016/s0550-3213(01)00184-5

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