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On the strong coupling behavior of heterotic and type I orbifolds

Andrea Gregori
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Abstract

We study the bulk effective theory of a class of orbifolds of the type IIB string with D5-branes, compactified to four dimensions. These constructions are connected, in a region of their moduli space, to some orbifolds of the type I and heterotic string. We compare the effective actions through the coupling of the R^2 term, and we argue that these orbifolds provide non-perturbative deformations of the latter, in which the gauge group is entirely non-perturbative.

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Andrea Gregori. 2000-10-11. On the strong coupling behavior of heterotic and type I orbifolds. https://doi.org/10.1088/1126-6708%2F2001%2F03%2F024

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