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arXiv · hep-th/9507158

Fivebranes, Membranes and Non-Perturbative String Theory

Katrin Becker·Melanie Becker·Andrew Strominger
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Abstract

Non-perturbative instanton corrections to the moduli space geometry of type IIA string theory compactified on a Calabi-Yau space are derived and found to contain order $e^{-1/g_s}$ contributions, where $g_s$ is the string coupling. The computation reduces to a weighted sum of supersymmetric extremal maps of strings, membranes and fivebranes into the Calabi-Yau space, all three of which enter on equal footing. It is shown that a supersymmetric 3-cycle is one for which the pullback of the Kähler form vanishes and the pullback of the holomorphic three-form is a constant multiple of the volume element. Quantum mirror symmetry relates the sum in the IIA theory over supersymmetric, odd-dimensional cycles in the Calabi-Yau space to a sum in the IIB theory over supersymmetric, even-dimensional cycles in the mirror.

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Katrin Becker, Melanie Becker, Andrew Strominger. 1995-09-27. Fivebranes, Membranes and Non-Perturbative String Theory. https://doi.org/10.1016/0550-3213(95)00487-1

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