Related papers: Stabilization of the Electroweak Vacuum by a Scala…
The fundamental Higgs doublet may be replaced in the Standard Model by certain non-perturbative four-quark interactions, whose effect is to induce a composite Higgs sector responsible for electroweak symmetry breaking. A simple composite…
The measured (central) values of the Higgs and top quark masses indicate that the Standard Model (SM) effective potential develops an instability at high field values. The scale of this instability, determined as the Higgs field value at…
We examine an extension of the SM Higgs sector by a Higgs triplet taking into consideration the Higgs-like particle discovery at the LHC with mass around 125 GeV. We evaluate the bounds on the scalar potential through the unitarity of the…
The Standard Model of electroweak interactions has one scalar doublet. The minimal extension of this sector is effected by adding a neutral, singlet scalar field. Depending on whether the singlet field has a non-zero vacuum expectation…
It is shown that, nonminimal coupling between the Standard Model (SM) Higgs field and spacetime curvature, present already at the renormalizable level, can be fine-tuned to stabilize the electroweak scale against power-law ultraviolet…
If the recent detection of $B-$mode polarization of the Cosmic Microwave Background by BICEP2 observations, withstand the test of time after the release of recent PLANCK dust polarisation data, then it would surprisingly put the…
Our current measurements of the Standard Model parameters imply that the Higgs field resides in a metastable electroweak vacuum, where the vacuum can decay to a lower ground state, with cataclysmic repercussions for our Universe. According…
Electroweak precision data have been extensively used to constrain models containing physics beyond that of the Standard Model. When the model contains Higgs scalars in representations other than singlets or doublets, and hence rho not…
This article considers three non-zero hypercharge triplets as an extension of the Standard Model Higgs doublet. Under extra $U(1)_{L_{\mu}-L_{\tau}}$ symmetry, the triplets are charged. We examine the stability of the electroweak vacuum at…
In the Higgs portal framework, the Higgs field generally mixes with the Standard Model singlet leading to the existence of two states, one of which is identified with the 125 GeV scalar observed at the LHC. In this work, we analyse direct…
We investigate the standard model (SM) with the extension of a charged scalar having fractional electromagnetic charge of $-1/3$ unit and with lepton and baryon number violating couplings at tree level. Without directly taking part in the…
Light, electrically charged vector-like `leptons' with order one Yukawa couplings can enhance the Higgs to diphoton decay rate, as is suggested by measurements of the signal strength \mu_{\gamma\gamma} by ATLAS and CMS. However, the large…
We propose a theoretical justification for the anomalous Higgs couplings without extending the particle content of the Standard Model, but rather assuming different realization of the electroweak symmetry and the representation of the Higgs…
Within the context of supergravity-coupled supersymmetry, fields which are gauge and global singlets are usually considered anathema. Their vacuum expectation values are shifted by quadratically divergent tadpole diagrams which are cutoff…
Current measurements of Standard Model parameters suggest that the electroweak vacuum is metastable. This metastability has important cosmological implications, because large fluctuations in the Higgs field could trigger vacuum decay in the…
Existing models of dynamical electroweak symmetry breaking (EWSB) find it very difficult to get a Higgs of mass lighter than $m_t$. Consequently, in light of the LHC discovery of the ~125 GeV Higgs, such models face a significant obstacle.…
Scalar singlet dark matter is one of the simplest and most predictive realisations of the WIMP (weakly-interacting massive particle) idea. Although the model is constrained from all directions by the latest experimental data, it still has…
We consider a minimal extension of the standard model where a real, gauge singlet scalar field is added to the standard spectrum. Introducing the Ansatz of universality of scalar couplings, we are led to a scenario which has a set of very…
It is widely believed that the top loop corrections to the Higgs effective potential destabilise the electroweak (EW) vacuum and that, imposing stability, lower bounds on the Higgs mass can be derived. With the help of a scalar-Yukawa…
In this article we examine the prospect of first order phase transition with a Y=0 real $SU(2)$ triplet extension of the Standard Model, which remains odd under $Z_2$, considering the observed Higgs boson mass, perturbative unitarity, dark…