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تسجيل مستخدم جديدEffects of Dimension-5 Operators in $E_6$ Grand Unified Theories
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Chao-Shang Huang
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The effective dimension-5 operators can be induced by quantum gravity or inspired by string and M theories. They have important impacts on grand unified theories. We investigate the group theoretic nature of them for the well known E(6) model. Considering the breaking chains $E_{6}mapsto H=SO(10)times U_{V}(1)mapsto SU(5)times U_{V}(1)times U_{V}(1)mapsto SU(3)times SU(2)times U_{Z}(1)times U_{V}(1)times U_{V}(1)$ and $E_{6}mapsto H=SO(10)times U_{V}(1)mapsto SU(4)times SU_{L}(2)times SU_{R}(2)times U_{V}(1)mapsto SU(3)times SU_{L}(2)times SU_{R}(2)times U_{S}(1)times U_{V}(1)$, we derive and give all of the Clebsch-Gordan coefficients $Phi^{(r)}_{s,z}$ associated with $E_6$ breaking to the standard model. Some applications of the results are discussed shortly.
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