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arXiv · hep-th/0610007

D-branes at Singularities, Compactification, and Hypercharge

Matthew Buican·Dmitry Malyshev·David R. Morrison·Martijn Wijnholt·Herman Verlinde
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Abstract

We report on progress towards the construction of SM-like gauge theories on the world-volume of D-branes at a Calabi-Yau singularity. In particular, we work out the topological conditions on the embedding of the singularity inside a compact CY threefold, that select hypercharge as the only light U(1) gauge factor. We apply this insight to the proposed open string realization of the SM of hep-th/0508089, based on a D3-brane at a dP_8 singularity, and present a geometric construction of a compact Calabi-Yau threefold with all the required topological properties. We comment on the relevance of D-instantons to the breaking of global U(1) symmetries.

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Matthew Buican, Dmitry Malyshev, David R. Morrison, Martijn Wijnholt, Herman Verlinde. 2006-10-26. D-branes at Singularities, Compactification, and Hypercharge. https://doi.org/10.1088/1126-6708%2F2007%2F01%2F107

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