Related papers: Avoiding Death by Vacuum
A vast literature on the theory and phenomenology of Two-Higgs-Doublet models (2HDM) exists since long. However, the present situation demands a revisit of some 2HDM properties. Now that a 125 GeV scalar resonance has been discovered at the…
We study constraints to avoid deep unrealistic minima in the next-to-minimal supersymmetric standard model. We analyze a scalar potential along directions where all of and one of the three Higgs fields develop their vacuum expectation…
The so-called metastability bound asserts that an unnaturally small Higgs mass is a necessary condition for electroweak vacuum metastability, offering a new approach towards solving the hierarchy problem. So far, this result relies on the…
The recent report by the CMS Collaboration on the excess of top and anti-top pair production is examined with regard to the improvement of vacuum stability under two simple scenarios: one with the existence of toponium $(\eta_t)$, and the…
If the new boson is lying in the narrow mass range between 122 - 127 GeV is confirmed to be a Higgs boson, then stability of the electroweak vacuum in a minimal model with a universal extra dimension (mUED) will require a much lower cutoff…
We study the stability of the electroweak vacuum in low-scale inflation models whose Hubble parameter is much smaller than the instability scale of the Higgs potential. In general, couplings between the inflaton and Higgs are present, and…
We construct a supersymmetric version of the Standard Model which contains a long-lived metastable vacuum. In this vacuum supersymmetry is broken and the electroweak symmetry is Higgsed, and we identify it with the physical ground state of…
It is possible that the electroweak scale is low due to the fine-tuning of microscopic parameters, which can result from selection effects. The experimental discovery of new light fundamental scalars other than the Standard Model Higgs…
Testing the stability of the electroweak vacuum in any extension of the Standard Model Higgs sector is of great importance to verify the consistency of the theory. Multi-scalar extensions as the Minimal Supersymmetric Standard Model…
Multiple electroweak phase transitions occurring sequentially in the early universe can give rise to intriguing phenomenology, compared to the typical single-step electroweak phase transition. In this work, we investigate this scenario…
Two-Higgs-doublet models (2HDMs) are minimal extensions of the Standard Model (SM) that may still be discovered at the LHC. The quartic couplings of their potentials can be determined from the measurement of the masses and branching ratios…
Since the discovery of a Higgs particle the effective Higgs potential of the Standard Model or extensions and the stability of the ground state corresponding to its minimum at the electroweak scale have been subject to a lot of…
The left-right symmetric model (LRSM), originally proposed to explain parity violation in low energy processes, has since emerged as an attractive framework for light neutrino masses via the seesaw mechanism. The scalar sector of the…
In this work we investigate the CP-conserving two-Higgs-doublet model (2HDM) in two realizations: a classically conformal setup (C2HDM) and a non-conformal setup with explicit tree-level quadratic mass terms (NC2HDM). Imposing current…
The Two Higgs Doublet model and its phenomenological implications are discussed. A brief survey on the present status of this model is given. In particular, we concentrate on the Two Higgs Doublet Model with Flavor Changing Neutral…
The simplest extension of the Standard Model by only one real singlet scalar can explain the observed dark matter relic density while giving simultaneously a strongly first-order electroweak phase transition in the early universe. However,…
It was observed recently by Randall and Wise that, any particle in the Standard Model cannot decay to $e^+e^-$ and $\gamma \gamma$ final states with comparably measurable branching ratios. This is also true for most extensions of the…
We re-evaluate the constraints on the parameter space of the minimal supersymmetric standard model from tunneling to charge- and/or color-breaking minima, taking into account thermal corrections. We pay particular attention to the region…
We study the electroweak phase transition in the alignment limit of the CP-conserving two-Higgs-doublet model (2HDM) of Type I and Type II. The effective potential is evaluated at one-loop, where the thermal potential includes Daisy…
Extending the Higgs sector of the Standard Model (SM) by just one additional Higgs doublet field leads to the two-Higgs-doublet model (2HDM). In the Type-I $Z_2$-symmetric limit of the 2HDM, all the five new physical Higgs states can be…