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arXiv · hep-th/9710078

U-duality and D-brane Combinatorics

B. Pioline·E. Kiritsis
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Abstract

We investigate D-brane instanton contributions to R^4 couplings in any toroidal compactification of type II theories. Starting from the 11D supergravity one-loop four-graviton amplitude computed by Green, Gutperle and Vanhove, we derive the non-perturbative O(e^{-1/λ}) corrections to R^4 couplings by a sequence of T-dualities, and interpret them as precise configurations of bound states of D-branes wrapping cycles of the compactification torus. Dp-branes explicitely appear as fluxes on D(p+2)-branes, and as gauge instantons on D(p+4)-branes. Specific rules for weighting these contributions are obtained, which should carry over to more general situations. Furthermore, it is shown that U-duality in D<=6 relates these D-brane configurations to O(e^{-1/λ^2}) instantons for which a geometric interpretation is still lacking.

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B. Pioline, E. Kiritsis. 1997-12-09. U-duality and D-brane Combinatorics. https://doi.org/10.1016/s0370-2693(97)01398-1

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