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Extension Bundles and the Standard Model

Bjorn Andreas·Gottfried Curio
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Abstract

We construct a new class of stable vector bundles suitable for heterotic string compactifications. Using these we describe a novel way to derive the fermionic matter content of the Standard Model from the heterotic string. For this we compactify on an elliptically fibered Calabi-Yau threefold X with two sections, the B-fibration, a variant of the ordinary Weierstrass fibration, which allows X to carry a free involution. We construct rank five vector bundles, invariant under this involution, such that turning on a Wilson line we obtain the Standard Model gauge group and find various three generation models. This rank five bundle is derived from a stable rank four bundle that arises as an extension of bundles pulled-back from the base and twisted by suitable line bundles. We also give an account of various previous results and put the present construction into perspective.

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Bjorn Andreas, Gottfried Curio. 2007-09-06. Extension Bundles and the Standard Model. https://doi.org/10.1088/1126-6708%2F2007%2F07%2F053

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