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Deconstruction, G_2 Holonomy, and Doublet-Triplet Splitting

Edward Witten
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Abstract

We describe a mechanism for using discrete symmetries to solve the doublet-triplet splitting problem of four-dimensional supersymmetric GUT's. We present two versions of the mechanism, one via ``deconstruction,'' and one in terms of M-theory compactification to four dimensions on a manifold of G_2 holonomy.

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Edward Witten. 2002-01-15. Deconstruction, G_2 Holonomy, and Doublet-Triplet Splitting. https://arxiv.org/abs/hep-ph/0201018

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