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Constructing 5d orbifold grand unified theories from heterotic strings

Tatsuo Kobayashi·Stuart Raby·Ren-Jie Zhang
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Abstract

A three-generation Pati-Salam model is constructed by compactifying the heterotic string on a particular T^6/Z_6 Abelian symmetric orbifold with two discrete Wilson lines. The compactified space is taken to be the Lie algebra lattice G_2+SU(3)+SO(4). When one dimension of the SO(4) lattice is large compared to the string scale, this model reproduces many features of a 5d SO(10) grand unified theory compactified on an S^1/Z_2 orbifold. (Of course, with two large extra dimensions we can obtain a 6d SO(10) grand unified theory.) We identify the orbifold parities and other ingredients of the orbifold grand unified theories in the string model. Our construction provides a UV completion of orbifold grand unified theories, and gives new insights into both field theoretical and string theoretical constructions.

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Tatsuo Kobayashi, Stuart Raby, Ren-Jie Zhang. 2004-03-05. Constructing 5d orbifold grand unified theories from heterotic strings. https://doi.org/10.1016/j.physletb.2004.04.058

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