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arXiv · 0704.3308

Instantons, Hypermultiplets and the Heterotic String

Nick Halmagyi·Ilarion V. Melnikov·Savdeep Sethi
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Abstract

Hypermultiplet couplings in type IIA string theory on a Calabi-Yau space can be quantum corrected by D2-brane instantons wrapping special Lagrangian cycles. On the other hand, hypermultiplet couplings in the heterotic string on a K3 surface are corrected by world-sheet instantons wrapping curves. In a class of examples, we relate these two sets of instanton corrections. We first present an analogue of the c-map for the heterotic string via a dual flux compactification of M-theory. Using this duality, we propose two ways of capturing quantum corrections to hypermultiplets. We then use the orientifold limit of certain F-theory compactifications to relate curves in K3 to special Lagrangians in dual type IIA compactifications. We conclude with some results from perturbative string theory for hypermultiplet F-terms and a conjecture about the topology of brane instantons.

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Nick Halmagyi, Ilarion V. Melnikov, Savdeep Sethi. 2007-08-01. Instantons, Hypermultiplets and the Heterotic String. https://doi.org/10.1088/1126-6708%2F2007%2F07%2F086

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