Related papers: Gaussian effective potential for the standard mode…
In the gauge-Higgs unification scenario the Higgs field is unified with gauge fields in higher dimensional gauge theory. The 4D Higgs field $H(x)$ corresponds to 4D fluctuations of the Aharonov-Bohm phase (Wilson line phase) $\theta_H$ in…
Starting from relativistic quantum field theories, describing interacting nucleons and pions coupled to the dynamical electromagnetic field, the pion degrees of freedom are eliminated by means of functional integration. Apart from taking…
We reconsider the Equivalence Theorem from an algebraic viewpoint, using an extended BRST symmetry. This version of the Equivalence Theorem is then used to reexpress the Abelian Higgs model action, originally written in terms of undesirable…
We consider renormalisable models extended in the scalar sector by a generic scalar field in addition to the standard model Higgs boson field, and work out the effective theory for the latter in the decoupling limit. We match the full…
Contrary to a widely spread believe, we have demonstrated that strongly coupled electroweak models including both a light Higgs-like boson and massive spin-1 resonances are not in conflict with experimental constraints on the oblique S and…
The Standard Model for electroweak interactions derives four vector gauge boson from an SU(2)xU(1) symmetry. A doublet of complex scalar (Higgs) bosons is added to generate masses by spontaneous symmetry breaking. Both, the four vector…
The one-loop effective action of the abelian and nonabelian Higgs models has been studied in various gauges, in the context of instanton and sphaleron transition, bubble nucleation and most recently in nonequilibrium dynamics. Gauge…
The equivalence theorem states that the leading part of the amplitude for a process with external longitudinally polarized vector bosons is given by the amplitude in which the longitudinal vector bosons are replaced by the corresponding…
We consider a gauge extension of the electroweak sector of the Standard Model based on the group G_2 x SU(2)x U(1). The exceptional group G_2 is the smallest rank two group that contains SU(3) as a subgroup; the SU(3) prediction sin^2…
A model for strong, electroweak and gravitational interactions based on the local symmetry group $G=SU(3)\times SU(2)_{L}\times U(1)\times C$ where $C$ is the local conformal symmetry group is proposed. The natural minimal $G$-invariant…
Due to the mass gap between the Standard Model and possible New Physics states, electroweak effective approaches are appropriate. Although a linear realization of the electroweak symmetry breaking with the Higgs forming a doublet together…
An electroweak (EW) model has been investigated (Moffat) in which the energy $E < \mu=\sqrt{\lambda}M_W$, where $\lambda$ is a gauge parameter and $M_W$ is the $W$ boson mass. For large enough $\lambda$ the scalar boson mass…
Gauge symmetries and Higgs mechanisms are key features of theories describing high-energy particle physics and collective phenomena in statistical and condensed-matter physics. In this review we address the collective behavior of systems of…
The global fit of the Standard Model to electroweak precision data, routinely performed by the LEP electroweak working groups and others, has been revisited in view of (i) the development of the new generic fitting package, Gfitter, (ii)…
Current data point toward metastability of the electroweak vacuum within the Standard Model. We study the possibility of stabilizing the Higgs potential in U(1) extensions thereof. A generic Z$'$ boson improves stability of the scalar…
Based on the observables $\MW$, $\Gamma_l$, $\bar\sw^2(\MZ^2)$, we evaluate the parameters $\Delta x, \Delta y$ and $\varepsilon$ at one-loop level within an electroweak massive vector-boson theory, which does not employ the Higgs…
We discuss how a model for the electroweak interactions without a Higgs could be embedded into a grand unified theory. The requirement of a non-trivial fixed point in the SU(2) sector of the weak interactions together with the requirement…
We consider a standard model extension equipped with a dark sector where the $U(1)_X^{}$ Abelian gauge symmetry is spontaneously broken by the dark Higgs mechanism. In this framework, we investigate patterns of the electroweak phase…
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.…
Gauge-invariant quantum fields are constructed in an Abelian power-counting renormalizable gauge theory with both scalar, vector and fermionic matter content. This extends previous results already obtained for the gauge-invariant…