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

We study Sogami’s generalized covariant derivative method for a SU(2)L × SU(2)R ×U(1)B−L × 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. ∗) E-mail address: [email protected] 1 typeset using PTPTEX.sty