Related papers: The Two Higgs Doublet Model and the Multiple Point…
The complex singlet-doublet model is a popular theory to account for dark matter and electroweak baryogenesis, wherein the Standard Model particle content is supplemented by a complex scalar gauge singlet, with certain discrete symmetries…
The Lee-Wick Standard Model is a highly constrained model which solves the gauge hierarchy problem at the expense of including states with negative norm. It appears to be macroscopically causal and consistent. This model is extended by…
In models with extended scalar sectors consisting of multiple Higgs doublets that trigger spontaneous electroweak symmetry breaking, it might be expected that the abundance of dimensionful quadratic couplings in the scalar potential could…
We explore the parameter regions in the complex Two Higgs Doublet Model (c2HDM) with explicit CP violation that can describe current LHC hints for one or more Higgs boson signals at 125 GeV. Such a simple extension of the Standard model has…
The two-Higgs doublet model (2HDM) provides an excellent benchmark to study physics beyond the Standard Model (SM). In this work we discuss how the behaviour of the model at high energy scales causes it to have a scalar with properties very…
We discuss the vacuum energy density term resulting from the spontaneous breakdown of the electroweak gauge symmetry, in the Higgs Mechanism. We alternatively expand the scalar field at one of the degenerate states that lie outside the…
In Two Higgs Doublet Models (2HDMs) shaped by some unbroken symmetry, imposing perturbativity requirements on the quartic couplings can imply that the allowed masses of all the fundamental scalars are bounded from above. This important…
We study the neutral minima of two-Higgs doublet models, showing that these potentials can have at least two such minima with different depths. We analyse the phenomenology of these minima for the several types of two-Higgs doublet…
The principle of multiple point criticality (PMPC), which allowed the prediction of the Higgs boson mass before its discovery, has so far been applied to radiatively generated vacua. If this principle is fundamental, following from some…
The natural cutoff scale for the quadratically divergent top quark contribution to the Higgs mass parameter can be significantly raised above the surprisingly low standard model value, with important consequences for the LHC: the physics…
We show that in two Higgs doublet models at tree-level the potential minimum preserving electric charge and CP symmetries, when it exists, is the global one. Furthermore, we derived a very simple condition, involving only the coefficients…
We show that there are regions of parameter space in multi-scalar doublet models where, in the first few hundred inverse femtobarns of data, the new charged and neutral scalars are not directly observable at the LHC and yet the Higgs decay…
Two-Higgs-doublet models (2HDM) are simple extensions of the Standard Model (SM) where the scalar sector is enlarged by adding a weak doublet. As a result, the Higgs potential depends in general on several free parameters which have to be…
We study the Multi-critical Point Principle (MPP) in a complex singlet scalar extension of the Standard Model (CxSM). The MPP discussed in this study selects model parameters so that two low-energy vacua realized by scalar fields are…
The effective potential of electroweak theory with two massless Higgs doublets at finite temperature is studied. We investigate phase structure and critical temperature in this model by numerical analysis without high-temperature expansion.…
The Aligned Two-Higgs-Doublet Model (A2HDM) describes a particular way of enlarging the scalar sector of the Standard Model, with a second Higgs doublet which is aligned to first the one in flavour space. This implies the absence of…
In this work we study the production and decay of two CP-even Higgs bosons in the general CP-conserving two-Higgs doublet model at the LHC. We also study the limiting case of the decoupling scenario. For each Yukawa version of the model, we…
We show that the Two-Higgs-Doublet Model (2HDM) constrained by the two-loop-order requirement of cancellation of quadratic divergences is consistent with the existing experimental constraints. The model allows to ameliorate the little…
Quark models with four-fermion interaction including derivatives of fields in the strong coupling regime are used to implement composite-Higgs extensions of the Standard Model. In this approach the dynamical breaking of chiral symmetry…
In this work we review the status of tree-level vacuum stability in general two-Higgs doublet models. We also discuss the problem of Normal minima in some classes of potentials. In some of these potentials, Normal minima can coexist leading…