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Fine-Tuning Problem in a Left-Right Symmetric Model and Sogami's Generalized Covariant Derivative Method

Eizou Umezawa
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Abstract

We study Sogami's generalized covariant derivative method for a $SU(2)_{L} \times SU(2)_{R} \times U(1)_{B-L} \times SU(3)_{c}$ model that contains bi-doublet and triplet Higgs bosons. In particular, a detailed study is made on the minimization conditions of the Higgs potential. It is known that a minimization condition and certain phenomenology for a extra gauge boson mass derive a restriction on potential parameters, which requires fine-tuning. We show that the restriction can be reduced to a condition of Yukawa coupling constants giving a heavy mass of the right-handed tau neutrino in our model. We also discuss the consistency among parameter restrictions of our model by taking phenomenology of the Higgs boson masses into account.

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Eizou Umezawa. 1997-10-20. Fine-Tuning Problem in a Left-Right Symmetric Model and Sogami's Generalized Covariant Derivative Method. https://doi.org/10.1143/ptp.98.187

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