Related papers: Nullification of multi-Higgs threshold amplitudes …
Motivated by the discovery of a new scalar field and amelioration of the electroweak vacuum stability ascribed to a singlet scalar field embedded in the standard model (SM), we examine the implication of the perturbative unitarity in the SM…
Tree amplitudes of any gauge theory and gravity can be factorized into primitive three-particle amplitudes by the BCFW recursion relations. We show that the amplitudes at any perturbation order are given by tree amplitudes with additional…
The predictions for the Higgs mass in extensions of the Minimal Supersymmetric Standard Model are discussed. We propose a simple theory where the Higgs mass is modified at tree-level and one can achieve a mass around 125 GeV without…
We consider the supersymmetric extension of the Standard Model with neutrino Yukawa interactions and R-parity violation. We found that R-parity breaking term \lambda \nu H_u H_d leads to an additional F-type contribution to the Higgs scalar…
Many extensions of the Standard Model postulate the existence of new weakly coupled particles, the top partners, at or below the TeV scale. The role of the top partners is to cancel the quadratic divergence in the Higgs mass parameter due…
We examine a scenario where the Higgs is part of an approximate conformal field theory, and has a scaling dimension greater than one. Such an unparticle Higgs (or Unhiggs) can still break electroweak symmetry and unitarize WW scattering,…
We provide a new set of on-shell recursion relations for tree-level scattering amplitudes, which are valid for any non-trivial theory of massless particles. In particular, we reconstruct the scattering amplitudes from (a subset of) their…
If the Einstein field equations are employed at the tree level, then the decay of the standard model Higgs particle into two gravitons is shown to be independent of the gravitational coupling strength G. The result follows from the physical…
Recent measurements by the ATLAS and CMS experiments have excluded the Standard Model Higgs boson in the high mass region, even if it is produced with a significantly smaller cross section than expected. The bounds are dominated by the…
The gravitational mass-shift effect is investigated in the framework of the standard model with the energy cutoff regularization both for stationary and non-stationary backgrounds at the one-loop level. The problem concerning singularity of…
We consider models with any number of Higgs doublets and study the conditions for decoupling. We show that, under very general circumstances, all the quadratic coefficients of the scalar potential must be present, except in special cases,…
We propose a mechanism of Higgsless gauge symmetry breaking with a large mass hierarchy. We consider a 5D gauge theory on an orbifold $S^1/Z_2$. The gauge symmetry is broken by orbifolding and also nontrivial boundary conditions at fixed…
We consider a procedure for directly constructing general tree-level four-particle scattering amplitudes of massive spinning particles that are consistent with the usual requirements of Lorentz invariance, unitarity, crossing symmetry, and…
We review the role of the Higgs boson in preserving unitarity of the scattering amplitudes in the Standard Model (SM). We will look at the processes $\nu_e + \bar{\nu}_e \rightarrow W^-_L +W^+_L $, $ W^-_L + W^+_L \rightarrow W^-_L +W^+_L $…
We introduce the standard model of elementary particles and discuss the reasons why we have to modify it. Emphasis is put on the indications from the neutrinos and on the role of the Higgs particle; some promising theoretical ideas, like…
The critical values for the mass of the Higgs bosons, at which the theory becomes strongly interacting, are calculated using the equivalence theorem, at high energies this allows us to replace the longitudinally polarized gauge bosons in…
We first re-prove with a more complete method that the the minimum standard model, with the inclusion of the CKM-matrix, requires the T-odd/P-odd total cross section of two spin-1/2 particles to vanish in all orders\cite{gxu}. Then we study…
Boundary conditions on an extra-dimensional interval can be chosen to break bulk gauge symmetries and to reduce the rank of the gauge group. We consider this mechanism in models with gauge trinification. We determine the boundary conditions…
In this short note I present a simple calculation of the top quark and Higgs masses, based on the idea that in the standard model without elementary Higgs, the fact that the $U(1)_Y$ coupling becomes of the order of unity at the Landau…
In a spontaneously broken gauge theory we consider (sub)-processes in which one virtual intermediate state (it can be a Higgs or a gauge field) produces many on-shell Higgses and massive vector bosons. In the kinematic regime where all…