Related papers: Baryogenesis via Elementary Goldstone Higgs Relaxa…
Electroweak baryogenesis is severely challenged in its traditional settings: the Minimal Supersymmetric Standard Model, and in more general two Higgs doublet models. Fine tuning of parameters is required, or large couplings leading to a…
The cosmological relaxation mechanism proposed in [1] allows for a dynamically generated large separation between the weak scale and a theory cutoff, using a sharp change of theory behaviour upon crossing the limit between unbroken and…
Electroweak baryogenesis (EWBG) remains a theoretically attractive and experimentally testable scenario for explaining the cosmic baryon asymmetry. We review recent progress in computations of the baryon asymmetry within this framework and…
Motivated by 3.9 sigma evidence of a CP-violating phase beyond the standard model in the like-sign dimuon asymmetry reported by DO, we examine the potential for two Higgs doublet models (2HDMs) to achieve successful electroweak baryogenesis…
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…
The strength of electroweak symmetry breaking may substantially differ in the early Universe compared to the present day value. In the Standard Model, the Higgs vacuum expectation value (vev) vanishes and electroweak symmetry gets restored…
A simple and economical extension of the minimal standard electroweak gauge model (without right-handed neutrinos) by the addition of two heavy Higgs scalar triplets would have two significant advantages. \underline {Naturally} small…
Cold electroweak baryogenesis was proposed as a scenario to bypass generic problems of electroweak baryogenesis within the Standard Model. In this scenario, baryogenesis takes place during an electroweak symmetry breaking transition, which…
The measured values of the Standard Model (SM) parameters favors a shallow metastable electroweak (EW) vacuum surrounded by a deep global AdS or a runaway Minkowski minimum. Furthermore, fine-tuning is the only explanation for the Higgs…
In Little Higgs models, the Higgs mass is stabilized at the one-loop level by the mechanism of collective symmetry breaking. Typically, the basic ingredient of these models is a large(r) global symmetry group spontaneously broken at a scale…
In the context of the minimal SO(5) linear {\sigma}-model, a complete renormalizable Lagrangian -including gauge bosons and fermions- is considered, with the symmetry softly broken to SO(4). The scalar sector describes both the electroweak…
We show that a rotating axion field that makes a transition from a matter-like equation of state to a kination-like equation of state around the epoch of recombination can significantly ameliorate the Hubble tension, i.e., the discrepancy…
In this paper we embed the light stop scenario, a MSSM framework which explains the baryon asymmetry of the universe through a strong first order electroweak phase transition, in a top-down approach. The required low energy spectrum…
We propose a new scenario of the electroweak baryogenesis based on the properties of electroweak domain walls surrounding black holes in the Higgs phase vacuum of the extended Standard Model with 2-Higgs doublets. It is shown that there…
We argue that given the experimental constraints on the Higgs mass the least fine tuned parameter space of minimal supersymmetric standard model is with negative stop masses squared at the grand unification scale. While stop mass squared is…
We propose a new alternative for baryogenesis which resolves a number of the problems associated with GUT and electroweak scenarios, and which may allow baryogenesis even in modest extensions of the standard model. If the universe never…
The Higgs low-energy theorem gives a simple and elegant way to estimate the couplings of the Higgs boson to massless gluons and photons induced by loops of heavy particles. We extend this theorem to take into account possible nonlinear…
We build a minimal neutral naturalness model in which the top partners are not charged under QCD, with a pseudo Goldstone Higgs arising from $SO(5)/SO(4)$ breaking. The color-neutral top partners generate the Higgs potential radiatively…
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…
The conventional baryogenesis mechanism is based on the one Higgs doublet within the standard model, at the electroweak scale $T\sim 100 GeV$. In this model the strong first order phase transition due to the spontaneous symmetry breaking…