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arXiv · hep-th/0606259

Membrane and fivebrane instantons from quaternionic geometry

Sergei Alexandrov·Frank Saueressig·Stefan Vandoren
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Abstract

We determine the one-instanton corrections to the universal hypermultiplet moduli space coming both from Euclidean membranes and NS-fivebranes wrapping the cycles of a (rigid) Calabi-Yau threefold. These corrections are completely encoded by a single function characterizing a generic four-dimensional quaternion-Kahler metric without isometries. We give explicit solutions for this function describing all one-instanton corrections, including the fluctuations around the instanton to all orders in the string coupling constant. In the semi-classical limit these results are in perfect agreement with previous supergravity calculations.

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Sergei Alexandrov, Frank Saueressig, Stefan Vandoren. 2006-06-27. Membrane and fivebrane instantons from quaternionic geometry. https://doi.org/10.1088/1126-6708%2F2006%2F09%2F040

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