Related papers: Effective Aligned 2HDM with a DFSZ-like invisible …
We study a scale invariant extension of the standard model which can explain simultaneously dark matter and the hierarchy problem. In our set-up, we introduce a scalar and a spinor as two-component dark matter in addition to scalon field as…
We extend the two-Higgs doublet models of Type I and Type II by adding a real gauge-singlet scalar S dark matter candidate (2HDMS models). We impose theoretical constraints deriving from perturbativity, stability, unitarity and correct…
We explore some aspects of models with two and three SU(2) scalar doublets that lead to mass degeneracies among some of the physical scalars. In Higgs sectors with two scalar doublets, the exact degeneracy of scalar masses, without an…
We show that in an $SU(2)\otimes U(1)$ model with a DSF-like invisible axion it is possible to obtain (i) the convergence of the three gauge coupling constants at an energy scale near the Peccei-Quinn scale; (ii) the correct value for…
We study vortex solutions in Abelian Chern-Simons-Higgs theories with visible and hidden sectors. We first consider the case in which the two sectors are connected through a BF-like gauge mixing term with no explicit interaction between the…
We explore GxG unified theories with the visible and the hidden or dark sectors paired under a Z2 symmetry. Developing a system of 'asymmetric symmetry breaking' we motivate such models on the basis of their ability to generate dark baryons…
The effective quark models with quasilocal interaction are used for description of two composite Higgs doublets, in strong coupling (tricritical) regime below the compositeness scale \Lambda_{C}. The low energy effective action of Two-Higgs…
In the underlying Planck scale theory we introduce a certain type of discrete symmetry, which potentially brings the stability of the weak-scale hierarchy under control. Under the discrete symmetry the $\mu $-problem and the tadpole problem…
Axion and axion-like particle models are typically affected by a strong fine-tuning problem in conceiving the electroweak and the Peccei-Quinn breaking scales. Within the context of the Minimal Linear {\sigma} Model, axion-like particle…
We explore a new framework that furnishes a mechanism to simultaneously address the electroweak naturalness problem and the axion high quality problem. The framework is based on a doubly composite dynamics where the second confinement takes…
In this article we study the possibility that neutral and charged scalars lighter than the 125 GeV Higgs boson might exist within the framework of the $\mathcal{CP}$-conserving Aligned-two-Higgs-doublet model. Depending on which new scalar…
We perform a comprehensive phenomenological analysis of the Scale Invariant Two Higgs Doublet Model (\textit{SI2HDM})~\cite{Lee:2012jn}. In this framework, the electroweak symmetry breaking is triggered radiatively, and the entire scalar…
We consider the Higgs sector of multi-Higgs-doublet models in the presence of simple symmetries relating the various fields. We construct basis invariant observables which may in principle be used to detect these symmetries for any number…
The neutral component of an inert scalar multiplet with hypercharge can provide a stable dark matter particle when its real and imaginary parts have a splitting mass spectrum. Otherwise, a tree-level dark matter-nucleon scattering mediated…
We discuss a scenario consisting of an effective 4D theory containing fundamental and composite fields. The strong dynamics sector responsible for the compositeness is assumed to be of extra dimensional origin. In the 4D effective theory…
The minimal extension of the scalar sector of the standard model contains an additional real scalar field with no gauge quantum numbers. Such a field does not couple to the quarks and leptons directly but rather through its mixing with the…
We investigate the constraints and phenomenology of a three Higgs doublet model (3HDM) with a $\Z2\times\Z2$ symmetry, featuring two inert scalar doublets that give rise to a two-component dark matter (DM) scenario. We analyze the model's…
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…
One of the simplest viable models for dark matter is an additional neutral scalar, stabilised by a $\mathbb{Z}_2$ symmetry. Using the GAMBIT package and combining results from four independent samplers, we present Bayesian and frequentist…
We consider an extension of the scalar sector of the Standard Model with a single complex Higgs triplet $X$. Such extensions are the most economic, model-independent way of generating neutrino masses through triplet interactions. We show…