Related papers: Unitarity and Fermion Mass Generatation
Efforts to unify group-theoretically the standard-model gauge interactions with the generation structure of fermions and their mirror partners should be accompanied with the unification of the corresponding gauge couplings. In this paper…
We analyze causality and unitarity constraints in graviton scattering amplitudes, aiming to establish new bounds on theories with $U(1)$-gravitational anomalies, such as axion models or strongly-coupled gauge theories. For this purpose, we…
In the context of the minimal supersymmetric standard model (MSSM), we discuss the introduction of exotic matter below the string scale $M_X$ in order to achieve gauge unification at $M_X$ (a constraint of a large class of string models).…
The discovery of a new boson with a mass of approximately 125 GeV in 2012 at the LHC has heralded a new era in understanding the nature of electroweak symmetry breaking and possibly completing the standard model of particle physics. Since…
A Yukawa-Higgs model with Ginsparg-Wilson (GW) fermions, proposed recently by Bhattacharya, Martin and Poppitz as a possible lattice formulation of chiral gauge theories, is studied. A simple argument shows that the gauge boson always…
Numerical evidence for a new dynamical mechanism of elementary particle mass generation has been found by lattice simulation in a simple, yet highly non-trivial SU(3) gauge model where a SU(2) doublet of strongly interacting fermions is…
We present an approach of mass generation for Standard Model particles in which fermions acquire masses from their interactions with physical vacuum and gauge bosons acquire masses from charge fluctuations of vacuum. A remarkable fact of…
We study the scattering of longitudinally polarized W bosons in extensions of the Standard Model where anomalous Higgs couplings to gauge sector and higher order O(p^4) operators are considered. These new couplings with respect to the…
The possibility of non-trivial representations of the gauge group on wavefunctionals of a gauge invariant quantum field theory leads to a generation of mass for intermediate vector and tensor bosons. The mass parameters m show up as central…
The $W$ boson mass $m_W$ in the GUT inspired $SO(5) \times U(1) \times SU(3)$ gauge-Higgs unification in the Randall-Sundrum (RS) warped space is evaluated. The muon decay $\mu^- \rightarrow e^- \bar{\nu}_e \nu_\mu$ proceeds by the exchange…
In this letter, we study collider phenomenology in the supersymmetric Standard Model with a certain type of non-universal gaugino masses at the gauge coupling unification scale, motivated by the little hierarchy problem. In this scenario,…
Perturbative unitarity conditions have been playing an important role by estimating the energy scale of new physics, including the Higgs mass as one of the most important examples. In this letter, we show that there is a possibility to see…
A constraint on masses of superheavy gauge and Higgs multiplets at the grand unification (GUT) scale is obtained from the gauge coupling unification in the case of high-scale supersymmetry. We found that all of the particles may lie around…
Measuring the Higgs couplings accurately at colliders is one of the best routes for finding physics Beyond the Standard Model (BSM). If the measured couplings deviate from the SM predictions, then this would give rise to energy-growing…
We impose partial-wave unitarity on $2 \to 2$ tree-level scattering processes to derive constraints on the dimensions of large scalar and fermionic multiplets of arbitrary gauge groups. We apply our results to scalar and fermionic…
The observed replication of fermions in three families is undoubtedly a reflection of a deeper symmetry underlying the standard model. In this paper we investigate one very elementary possibility, that physics above the grand unification…
The string landscape suggests that the supersymmetry breaking scale can be high, and then the simplest low energy effective theory is the Standard Model (SM). Considering grand unification scale supersymmetry breaking, we show that gauge…
The fermion mass problem and the ideas of mass protection are briefly reviewed. The Fritzsch ansatz for the quark mass matrices and a recent variant, based on a lightest flavour mixing mechanism in which all the CKM mixing angles disappear…
An electroweak model in which the masses of the W and Z bosons and the fermions are generated by quantum loop graphs through a symmetry breaking is investigated. The model is based on a regularized quantum field theory in which the quantum…
Measuring the Higgs couplings accurately at colliders is one of the best routes for finding physics Beyond the Standard Model (BSM). If the measured couplings deviate from the SM predictions, then this would give rise to energy-growing…