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arXiv · hep-th/9506112

K3--Fibrations and Heterotic-Type II String Duality

A. Klemm·W. Lerche·P. Mayr
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Abstract

We analyze the map between heterotic and type II N=2 supersymmetric string theories for certain two and three moduli examples found by Kachru and Vafa. The appearance of elliptic j-functions can be traced back to specializations of the Picard-Fuchs equations to systems for $K_3$ surfaces. For the three-moduli example we write the mirror maps and Yukawa couplings in the weak coupling limit in terms of j-functions; the expressions agree with those obtained in perturbative calculations in the heterotic string in an impressive way. We also discuss symmetries of the world-sheet instanton numbers in the type II theory, and interpret them in terms of S--duality of the non-perturbative heterotic string.

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A. Klemm, W. Lerche, P. Mayr. 1995-06-18. K3--Fibrations and Heterotic-Type II String Duality. https://doi.org/10.1016/0370-2693(95)00937-g

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