We revisit type I compactifications with a Spin( 32)/Z(2) gauge bundle that admits no vector structure. We elucidate the relation of this Z(2) obstruction to discrete B-field flux and to 't Hooft flux and clarify some subtleties in the T-duality transformation to type IIA intersecting D-brane models. We reexamine the earliest 3-generation GUT model on magnetized D-branes and show its consistency when a discrete B-flux is switched on. We further generalize partially known results for toroidal models to type I compactifications without vector structure and their mirror dual type IIA orientifolds on genuine Calabi-Yau manifolds. We illustrate this by working out the example of the quintic in some detail.
Bachas, C., Bianchi, M., Blumenhagen, R., Lust, D., Weigand, T. (2008). Comments on orientifolds without vector structure. JOURNAL OF HIGH ENERGY PHYSICS(8) [10.1088/1126-6708/2008/08/016].
Comments on orientifolds without vector structure
Bianchi M.;
2008-01-01
Abstract
We revisit type I compactifications with a Spin( 32)/Z(2) gauge bundle that admits no vector structure. We elucidate the relation of this Z(2) obstruction to discrete B-field flux and to 't Hooft flux and clarify some subtleties in the T-duality transformation to type IIA intersecting D-brane models. We reexamine the earliest 3-generation GUT model on magnetized D-branes and show its consistency when a discrete B-flux is switched on. We further generalize partially known results for toroidal models to type I compactifications without vector structure and their mirror dual type IIA orientifolds on genuine Calabi-Yau manifolds. We illustrate this by working out the example of the quintic in some detail.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
