Grand Unification: Modified Value of CGCoefficient For SU(5) Model Using Vacuum Polarization

Abstract

The grand unification basically provides unification of strong, hypercharge and weak couplings by the gauge group of standard model, SU(3)⊗SU(2)⊗U(1) having coupling constants for each group and Weinberg angle. In this paper the convergence of coupling constants is achieved using SU(5) model at GeV energy level, although earlier it was turned out that in the SU(5) model, the coupling constants do not come together at one point at energies of GeV scale. The value of Clebsch-Gordon coefficient is modified taking into account the vacuum polarization function; as the running coupling constants of the gauge group SU(3)⊗SU(2)⊗U(1) can be calculated only from vacuum polarization. The obtained value for sinθWis sinθW = 0.233 + 0.00276/-0.00243 and accordingly θW varies from 28.717° to 29.068°. The calculated value of coupling constant is αun = 0.034016