Cancellation of Leading Divergencies in Left-Right Electroweak Model and Heavy Particles

The fine-tuning principles are analyzed in search for estimations of heavy particle masses in the left-right (LR) symmetric model. The modification of Veltman condition based on the hypothesis of the compensation between fermion and boson vacuum energies within the LR Model multiplets is proposed. The hypothesis is supplied with the requirement of the stability under rescaling. With regard to these requirements the necessity of existence of right-handed Majorana neutrinos with masses of order of right-handed gauge bosons is shown and estimations on the top-quark mass which are in a good agreement with the experimental value are obtained.