Related papers: Can Electroweak Theory Without A Higgs Particle Be…
According to the conventional concept of the gauge field theory, the local gauge invariance excludes the possibility of giving a mass to the gauge boson without resorting to the Higgs mechanism because the Lagrangian constructed by adding a…
The existence of a mass gap between the Standard Model (SM) and possible new states encourages us to use effective field theories. Here we follow the non-linear realization of the electroweak symmetry breaking: the electroweak effective…
While it is often stated that the notion of electroweak (EW) naturalness in supersymmetric models is subjective, fuzzy and model-dependent, here we argue the contrary: electroweak naturalness can be elevated to a {\it principle} which is…
A Lagrangian of electroweak interactions without Higgs is used to study the contributions of quarks and leptons to the masses of the W and the Z bosons. It is shown that the $SU(2)\times U(1)$ symmetry is broken by both fermion masses and…
The electroweak symmetry may be broken by a composite Higgs which arises naturally as a bound state of the top quark if the standard model gauge fields and fermions propagate in extra dimenions. The top quark mass and the Higgs mass can be…
The electric charge renormalization constant, as defined in the Thomson limit, is expressed in terms of self-energies of the photon-Z-boson system in an arbitrary R_\xi-gauge to all perturbative orders. The derivation as carried out in the…
Recently, realistic theories of electroweak symmetry breaking have been constructed in which the electroweak symmetry is broken by boundary conditions imposed at a boundary of higher dimensional spacetime. These theories have equivalent 4D…
Models of Gauge-Higgs unification in extra dimensions offer a very elegant playground where one can study electroweak symmetry breaking. The nicest feature is that gauge symmetry itself protects the Higgs potential from divergences, thus…
Standard theories of electroweak interactions are based on the concept of a gauge symmetry broken by the Higgs mechanism. If they are placed in an environment with a sufficiently high temperature, the symmetry gets restored. It turns out…
The electroweak sector of the Standard Model can be formulated in a way similar to Chiral Perturbation Theory (ChPT), but extended by a singlet scalar. The resulting effective field theory (EFT) is called Higgs-Electroweak Chiral Lagrangian…
Assuming the existence of a supersymmetric U(1) gauge factor at the TeV energy scale (motivated either by the superstring-inspired E_6 model or low-energy electroweak phenomenology), several important consequences are presented. The…
In a recent paper, we introduced a new Little Higgs model, which contains the gauge structure $SU(2)^3\times U(1)$, embedded in an approximate global $SO(5)\times SO(5)$ symmetry. After breaking to the standard model, $SU(2)_L \times…
We review the empirical evidence for the validity of the Standard Electroweak Theory in Nature. The experimental data are interpreted in terms of an effective Lagrangian for Z physics, allowing for potential sources of SU(2) violation and…
We point out that it is possible to associate the electroweak Higgs boson with the pseudo-Goldstone boson of broken scale invariance, thus resolving the hierarchy problem in a technically natural way. We illustrate this idea with two…
We show that scalar unparticles coupled to the Standard Model Higgs at the renormalizable level can have a dramatic impact in the breaking of the electroweak symmetry already at tree level. In particular one can get the proper electroweak…
A careful renormalization group analysis of the electroweak Standard Model, considered as a low energy effective theory, reveals that there is no hierarchy problem in the broken phase of the SM. In the broken phase a light Higgs turns out…
The main challenge faced by Higgsless models of electroweak symmetry breaking is to reconcile the experimental constraints imposed by the precision electroweak data and the top quark phenomenology with the unitarity constraints imposed by…
Theoretical arguments suggest that the Higgs sector of the standard model is an effective theory. We parametrize the new physics by means of an effective Lagrangian technique and study its effect on the energy of the electroweak sphaleron.…
We investigate an effective model for the finite temperature restoration phase transition of the electroweak theory. It is obtained by dimensional reduction of the $3+1$ dimensional full theory and by subsequent integration over all static…
A renormalizable model of electroweak interaction which coincides with Weinberg-Salam model in the gauge boson - fermion sector but does not require the existence of fundamental scalar fields is proposed.