Related papers: A common scenario for an small vacuum energy and l…
In the present work it is shown that some specific double Higgs like mechanisms may have interesting cosmological applications. A hidden scenario which cast long lived super heavy particles together with an extremely light particle $a$ with…
A dynamical mechanism of symmetry breaking in which gauge and matter fields play an active role is proposed. It basically represents a covariant generalization of the mechanism responsible for superconductivity, and provides a {\em natural}…
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…
A dynamical model for the dark energy is presented in which the ``quintessence'' field is the axion, $a_Z$, of a spontaneously broken global $U(1)_{A}^{(Z)}$ symmetry whose potential is induced by the instantons of a new gauge group…
We construct a little Higgs model with the most minimal extension of the standard model gauge group by an extra U(1) gauge symmetry. For specific charge assignments of scalars, an approximate U(3) global symmetry appears in the…
It has recently been shown that a subdominant hidden sector of atomic dark matter in the early universe provides a novel avenue towards resolving the Hubble ($H_0$) tension while maintaining good agreement with Cosmic Microwave Background…
We study constraints on the hidden sector model mediated by an additional SU(2) Higgs doublet from the phenomenology of Higgs bosons. The hidden sector is assumed to contain a hidden U(1) gauge symmetry and the hidden U(1) gauge boson gets…
We consider theories where dark matter is composed of a thermal relic of weak scale mass, whose couplings to the Standard Model (SM) are however too small to give rise to the observed abundance. Instead, the abundance is set by annihilation…
In a recent model of dark energy (with several phenomenological consequences), the universe is assumed to be trapped in a false vacuum with an energy density of the order of (10^{-3} eV)^4, mimicking the presently successful $\Lambda CDM$…
We consider a class of models with extra complex scalars that are charged under both the Standard Model and a hidden strongly coupled $SU(N)_H$ gauge sector, and discuss the scenarios where the new scalars are identified as the messenger…
Cosmologically long-lived, composite states arise as natural dark matter candidates in theories with a strongly interacting hidden sector at a scale of 10 - 100 TeV. Light axion-like states, with masses in the 1 MeV - 10 GeV range, are also…
We discuss a dark family of lepton-like particles with their own "private" gauge bosons under a local SU'(2)xU'(1) symmetry. The product of dark and visible gauge groups SU'(2)xU'(1)xSU_w(2)xU_Y(1) is broken dynamically to the diagonal…
We suggest that dark matter can be identified with a stable composite fermion X^0, that arises within the holographic AdS/CFT models, where the Higgs boson emerges as a composite pseudo-goldstone boson. The predicted properties of X^0…
We examine the possibility that dark matter may be the manifestation of dark forces of a hidden sector, i.e. "Dark Force = Dark Matter." As an illustrative and minimal example we consider the hidden SU(2)_h x U(1)_h gauge group. The hidden…
We identify possible dark matter candidates within the class of strongly interacting models where electroweak symmetry breaking is triggered by a light composite Higgs boson. In these models, the Higgs boson emerges as a Holographic…
We propose that the universe contains two identical sets of particles and gauge interactions, coupling only through gravitation, which differ by their Higgs potentials. We postulate that because of underlying symmetries, the two sectors…
Based on the analogy with superconductor physics we consider a scalar-vector-tensor gravitational model, in which the dark energy action is described by a gauge invariant electromagnetic type functional. By assuming that the ground state of…
We show that dark matter could be made of massive gauge bosons whose stability doesn't require to impose by hand any discrete or global symmetry. Stability of gauge bosons can be guaranteed by the custodial symmetry associated to the gauge…
We propose a low scale leptogenesis scenario in the framework of composite Higgs models supplemented with singlet heavy neutrinos. One of the neutrinos can also be considered as a dark matter candidate whose stability is guaranteed by a…
The idea that a background of invisible material pervades the whole universe is as old as the history of natural philosophy. Modern particle physics and cosmology support that idea and identify in the cosmic vacuum the ultimate source of…