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arXiv · 0812.2783

A note on dimension-5 operators in GUTs and their impact

Joydeep Chakrabortty·Amitava Raychaudhuri
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Abstract

Quantum gravity or string compactification can lead to effective dimension-5 operators in Grand Unified Theories which modify the gauge kinetic terms. We exhaustively discuss the group-theoretic nature of such operators for the popular SU(5), SO(10), and E(6) models. In particular, for SU(5) only a Higgs in the 200 representation can help bring the couplings to unification below the Planck scale and in consistency with proton decay limits while for a supersymmetric version 24, 75, or 200 representations are all acceptable. The results also have a direct application in non-universality of gaugino masses in a class of supersymmetric models where identical group-theoretic features obtain.

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Joydeep Chakrabortty, Amitava Raychaudhuri. 2009-03-04. A note on dimension-5 operators in GUTs and their impact. https://doi.org/10.1016/j.physletb.2009.01.065

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