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arXiv · hep-th/9707126

Heterotic / type I duality and D-brane instantons

C. Bachas·C. Fabre·E. Kiritsis·N. A. Obers·P. Vanhove
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Abstract

We study heterotic/type I duality in d=8,9 uncompactified dimensions. We consider the special (``BPS saturated'') F^4 and R^4 terms in the effective one-loop heterotic action, which are expected to be non-perturbatively exact. Under the standard duality map these translate to tree-level, perturbative and non-perturbative contributions on the type I side. We check agreement with the one-loop open string calculation, and discuss the higher-order perturbative contributions, which arise because of the mild non-holomorphicities of the heterotic elliptic genus. We put the heterotic world-sheet instanton corrections in a form that can be motivated as arising from a D-brane instanton calculation on the type-I side.

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C. Bachas, C. Fabre, E. Kiritsis, N. A. Obers, P. Vanhove. 1997-10-21. Heterotic / type I duality and D-brane instantons. https://doi.org/10.1016/s0550-3213(97)00639-1

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