Authors: Andrés Collinucci Raffaele Savelli
Publish Date: 2012/02/07
Volume: 2012, Issue: 2, Pages: 15-
Abstract
We study the problem of fourform flux quantization in Ftheory compactifications We prove that for smooth elliptically fibered CalabiYau fourfolds with a Weierstrass representation the flux is always integrally quantized This implies that any possible half integral quantization effects must come from 7branes ie from singularities of the fourfoldWe subsequently analyze the quantization rule on explicit fourfolds with SpN singularities and connect our findings via Sen’s limit to IIB string theory Via direct computations we find that the fourform is halfintegrally quantized whenever the corresponding 7brane stacks wrap nonspin complex surfaces in accordance with the perturbative FreedWitten anomaly Our calculations on the fourfolds are done via toric techniques whereas in IIB we rely on Sen’s tachyon condensation picture to treat bound states of branes Finally we give general formulae for the curvature and fluxinduced D3 tadpoles for general fourfolds with SpN singularities
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