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arXiv · hep-th/9707222

Calculable e^{-1/λ} Effects

I. Antoniadis·B. Pioline·T. R. Taylor
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Abstract

We identify and evaluate a class of physical amplitudes in four-dimensional N=4 superstring theory, which receive, in the weak coupling limit, contributions of order e^{-1/λ}, where λis the type II superstring coupling constant. They correspond to four-derivative \Ftilde_1 interaction terms involving the universal type II dilaton supermultiplet. The exact result, obtained by means of a one-loop computation in the dual heterotic theory compactified on T^6, is compared with the perturbation theory on the type II side, and the e^{-1/λ} contributions are associated to non-perturbative effects of Euclidean solitons (D-branes) wrapped on K3 x T^2. The ten-dimensional decompactification limit on the type IIB side validates the recent conjecture for the D-instanton-induced R^4 couplings.

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I. Antoniadis, B. Pioline, T. R. Taylor. 1997-10-21. Calculable e^{-1/λ} Effects. https://doi.org/10.1016/s0550-3213(97)00684-6

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