Related papers: One-Loop Charge-Breaking Minima in the Two-Higgs D…
We derive electroweak Z-string solutions in the Glashow-Weinberg-Salam model with two Higgs doublets. The existence of such solutions in particular requires a specific relation between the ratio of the two Higgs vacuum expectation values,…
We consider an extension of the Standard Model with one or more scalar multiplets beyond the Higgs doublet $\Phi$. The additional scalar multiplets are supposed to carry arbitrary hypercharges. We prove that, in such a model, if the field…
We consider the Standard Model with a new particle which is charged under $SU(2)_{L}$ with the hypercharge being zero. Such a particle is known as one of the dark matter (DM) candidates. We examine the realization of the multiple point…
We present a brief review of recent attempts to construct effective theories to describe the breaking of the electroweak symmetry in extensions of the Standard Model with new strongly interacting dynamics around the TeV scale. Particular…
The electroweak model is extended by a second Higgs doublet and a numerical investigation of static, finite energy classical solutions is performed. The results indicate that for a large domain of the parameters of the Higgs potential, the…
It is proved that the minimum of a general two Higgs doublet models' potential is stable at tree level. A relation between stability and flavour changing neutral currents at tree level is shown.
In these proceedings we explore the use of (non-linear) electroweak chiral Lagrangians for the description of possible beyond the Standard Model strong dynamics in the electroweak sector. Experimentally one observes an approximate…
We present a calculation of the decay rate of the electroweak vacuum, fully including all gravitational effects and a possible non-minimal Higgs-curvature coupling $\xi$, and using the three-loop Standard Model effective potential. Without…
We analyze a model for the Higgs sector with two scalar doublets and a $Z_2$ symmetry that is manifest in the Yukawa sector but broken in the potential. Thus, one of the doublets breaks the electroweak symmetry and has tree-level Yukawa…
In this talk we discuss the structure of electroweak low-energy effective theories where the Higgs is non-linearly realized, typically in scenarios where the Higgs is a pseudo Nambu-Goldstone boson of some beyond Standard Model symmetry.…
We study the finite-temperature effective potential of the Minimal Supersymmetric Standard Model, in the limit of only one light Higgs boson. Because of the large top Yukawa coupling, there can be significant differences with respect to the…
Lee-Wick partners to the Standard Model Higgs doublet may appear at a mass scale that is significantly lower than that of the remaining Lee-Wick partner states. The relevant effective theory is a two-Higgs doublet model in which one doublet…
If the Higgs mass m_H is as low as suggested by present experimental information, the Standard Model ground state might not be absolutely stable. We present a detailed analysis of the lower bounds on m_H imposed by the requirement that the…
Recently a new class of theories of electroweak symmetry breaking have been constructed. These models, based on deconstruction and the physics of theory space, provide the first alternative to weak-scale supersymmetry with naturally light…
Contrary to common belief, the requirement that supersymmetry exists and that there are two Higgs doublets and no singlet at the electroweak energy scale does not necessarily result in the minimal supersymmetric standard model (MSSM). An…
Making use of a dimensionally-reduced effective theory at high temperature, we perform a nonperturbative study of the electroweak phase transition in the Two Higgs Doublet model. We focus on two phenomenologically allowed points in the…
We propose a scenario of dynamical electroweak symmetry breaking which is applicable to the model with no tree-level potential for the elementary Higgs doublet field. An example of such a model is the gauge-Higgs unification model. The…
We make an attempt to identify regions in a Type II Two-Higgs Doublet Model, which correspond to a metastable electroweak vacuum with lifetime larger than the age of the universe. We analyse scenarios which retain perturbative unitarity up…
To study the convergence of the loop expansion at the high-temperature electroweak phase transition, we calculate the 2-loop effective potential of the 3d SU(2)-Higgs model in a general covariant gauge. We find that the loop expansion…
Severe constraints on parameters of the minimal supersymmetric standard model follow from a dynamical electroweak symmetry breaking mechanism dominated by top and stop loops. In particular, the lightest Higgs boson mass is expected to be…