Related papers: Strong electroweak phase transition from Supersymm…
We study scalar singlet extensions of the Standard Model (SM), focusing on scenarios where dark matter (DM) is stabilized by a \(\mathbb{Z}_2\) symmetry. In the minimal single-scalar extension of the SM, only a narrow region near the Higgs…
We show how a heavy scalar singlet with a large vacuum expectation value can evade the potential instability of the Standard Model electroweak vacuum. The quartic interaction between the heavy scalar singlet and the Higgs doublet leads to a…
In this paper we study phase transitions in a maximally symmetric composite Higgs model with next-to-minimal coset, where a pseudoscalar singlet emerges alongside the Higgs doublet. The maximal symmetry guarantees the finiteness of the…
In this note, a ``littlest higgs'' model is presented which has an approximate custodial SU(2) symmetry. The model is based on the coset space $SO(9)/(SO(5)\times SO(4))$. The light pseudo-goldstone bosons of the theory include a {\it…
We discuss the question if the upcoming generation of collider and low-energy experiments can successfully probe the nature of the electroweak phase transition. In particular, we are interested in phase transitions strong enough for…
In this work we shall consider the effects of a non-trivial topology on the effective potential of the Standard Model. Specifically we shall assume that the spacetime topology is $S^1\times R^3$ and we shall calculate the Standard Model…
In this talk we review the actual situation concerning electroweak phase transition and baryogenesis in the minimal supersymmetric extension of the Standard Model. A strong enough phase transition requires light Higgs and stop eigenstates.…
Phase transitions induced by high temperatures and strong magnetic fields are investigated in the Standard model. The consistent effective potential including the one-loop and ring diagram contributions is calculated and investigated for…
In composite Higgs models the Higgs is a pseudo-Goldstone boson of a high-energy strong dynamics. We have constructed the effective chiral Lagrangian for a generic symmetric coset, restricting to CP-even bosonic operators up to four momenta…
We study electroweak baryogenesis in the $SO(6)/SO(5)$ composite Higgs model with the third generation quarks being embedded in the $\textbf{20}'$ representation of $SO(6)$. The scalar sector contains one Higgs doublet and one real singlet,…
The Standard Model (SM) cannot explain the observed baryon asymmetry of the Universe (BAU), thus driving the need for physics beyond the SM, which can generate electroweak baryogenesis through a strong first-order electroweak phase…
We discuss CP-violation in a model with a real and a complex isospin triplet Higgs fields without introducing any symmetries except for the electroweak gauge symmetry. This corresponds to the minimal extension of the Higgs sector with the…
The future space-borne gravitational wave (GW) detectors would provide a promising probe for the new physics beyond the standard model that admits the first-order phase transitions. The predictions for the GW background vary sensitively…
We revisit an extension of the MSSM by adding a hypercharge-neutral, SU(2)-triplet chiral superfield. Similar to the NMSSM, the triplet gives an additional contribution to the quartic coupling in the Higgs potential, and the mass of the…
Electroweak baryogenesis is an attractive mechanism to generate the baryon asymmetry of the Universe via a strong first order electroweak phase transition. We compare the phase transition patterns suggested by the vacuum structure at the…
We analyze some features of the role that extra dimensions, of radius $R$ in the TeV$^{-1}$ range, can play in the soft breaking of supersymmetry and the spontaneous breaking of electroweak symmetry. We use a minimal model where the gauge…
We construct supersymmetric theories in which the correct scale for electroweak symmetry breaking is obtained without significant fine-tuning. We calculate the fine-tuning parameter for these theories to be at the 20% level, which is…
We study first-order electroweak phase transitions in the real-singlet extended Standard Model, for which non-zero mixing between the Higgs and the singlet can efficiently strengthen the transitions. We perform large-scale parameter space…
We demonstrate that Standard Model vacuum stability exhibits extreme sensitivity to the Higgs quartic coupling: a mere 3\% enhancement represents the critical threshold separating metastability from absolute stability with UV Landau poles.…
In collaboration with G.D. Moore, the electroweak phase transition in the minimal supersymmetric standard model is studied using the two-loop effective potential. We make a comprehensive search of the MSSM parameter space consistent with…