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تسجيل مستخدم جديدTheorem on vanishing contributions to $sin^2theta_W$ and intermediate mass scale in Grand Unified Theories with trinification symmetry
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We prove that the values of the electroweak mixing angle $sin^2theta_W$ and intermediate mass scale $M_I$ have vanishing contributions due to one-loop, two-loop and gravitational corrections in Grand Unified Theories which accommodate an intermediate trinification symmetry ($G_{333D}$) invoked with spontaneous D-parity mechanism operative at mass scale greater than $M_I$. The proof of theorem is robust and we verify the results numerically using supersymmetric as well as non-supersymmetric version of $E_6$-GUT.
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