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Gauge Coupling Unification with Extra Dimensions and Gravitational Scale Effects

Hsin-Chia Cheng·Bogdan A. Dobrescu·Christopher T. Hill
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Abstract

We study gauge coupling unification in the presence of extra dimensions compactified at a few TeV. Achieving unification requires a large number of gauge boson Kaluza-Klein excitations lighter than the string scale, such that the higher-dimensional gauge couplings are O(1) in string scale units. Corrections to the gauge couplings from two or more loops are about 10% or larger, hence string (or M) theory is generally expected to be strongly coupled in TeV-scale extra-dimensional scenarios. Higher-dimensional operators induced by quantum gravitational effects can shift the gauge couplings by a few percent. These effects are sufficiently large that even the minimal Standard Model, or the MSSM, allow unification at a scale in the TeV range. The strongly coupled unified theory may induce dynamical electroweak symmetry breaking.

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Hsin-Chia Cheng, Bogdan A. Dobrescu, Christopher T. Hill. 1999-07-08. Gauge Coupling Unification with Extra Dimensions and Gravitational Scale Effects. https://doi.org/10.1016/s0550-3213(99)00816-0

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