Fine tuning in the Standard Model and Beyond

TL;DR

This paper explores fine-tuning principles in the Standard Model and its extensions to predict particle masses, proposing a modified Veltman condition and analyzing implications for various models including two-Higgs and Left-Right symmetric models.

Contribution

It develops a modified Veltman condition based on vacuum energy compensation and applies it to predict particle masses in the Standard Model and beyond.

Findings

Predicts top-quark mass around 175 GeV and Higgs mass around 210 GeV in the Standard Model.

Provides mass intervals for top-quark compatible with experimental data in extended models.

Suggests the existence of right-handed Majorana neutrinos in the Left-Right model.

Abstract

The fine-tuning principles are examined to predict the top-quark and Higgs-boson masses. The modification of the Veltman condition based on the compensation of vacuum energies is developed. It is implemented in the Standard Model and in its minimal extension with two Higgs doublets and Left-Right symmetric Model. The top-quark and Higgs-boson couplings are fitted in the SM for the lowest ultraviolet scale where the fine-tuning can be stable under rescaling. It yields the low-energy values $m_t \simeq 175 GeV;\quad m_H \simeq 210 GeV$. For the Two-Higgs and Left-Right Symmetric Models the fine-tuning principles yield the interval for top-quark mass, compatible with the modern experimental data. For the Left-Right Model the FT principles demand the existence of the right-handed Majorana neitrinos with masses of order of right-handed gauge bosons.