Related papers: Dark Matter and Torsion
Usually considered highly speculative, tachyons can be treated via straightforward Einsteinian dynamics. Kinetic theory and thermodynamics for a gas of ``dark'' tachyons are readily constructed. Such a gas exhibits density and pressure…
When the minimal supersymmetric standard model is augmented by three right-handed neutrino superfields, one generically predicts that the neutrinos acquire Majorana masses. We postulate that all supersymmetry (SUSY) breaking masses as well…
It is known that two heavy Majorana right-handed neutrinos are sufficient to generate the baryon asymmetry in the present universe. Thus, it is interesting to identify the third right-handed neutrino $N$ with the dark matter. We impose a…
Dark matter is presumably made of some new, exotic particle that appears in extensions of the Standard Model. After giving a brief overview of some popular candidates, I discuss in more detail the most appealing case of the supersymmetric…
Extending the standard model with three right-handed neutrinos ($N_k$) and a second Higgs doublet ($\eta$), odd under the discrete parity symmetry $Z_2$, Majorana neutrino masses can be generated at 1-loop order. In the resulting model, the…
There exist several well-motivated candidates for non-baryonic cold dark matter, including neutralinos, axions, axinos, gravitinos, Wimpzillas. I review the dark matter properties of the neutralino and the current status of its detection. I…
Several lines of evidence suggest that some of the dark matter may be non-baryonic: the non-detection of various plausible baryonic candidates for dark matter inferred, e.g., from galaxy rotation curves and from cluster of galaxy velocity…
The seesaw mechanism with three heavy Majorana right-handed neutrinos provides an elegant explanation for neutrino masses and, combined with leptogenesis, can generate the baryon asymmetry of the universe (BAU). Naturally embedded in a…
Dark matter has been recognized as an essential part of matter for over 70 years now, and many suggestions have been made, what it could be. Most of these ideas have centered on Cold Dark Matter, particles that are predicted in extensions…
Dark matter (DM) is usually assumed to be stabilized by a symmetry, which is mostly considered to be $Z_2$. For example, in supersymmetry it is $R$ parity, i.e. $(-1)^{3B+L+2j}$. However, it may be $Z_n$ or $U(1)_D$, and derivable from…
We entertain the possibility that neutrino masses and dark matter (DM) originate from a common composite dark sector. A minimal effective theory can be constructed based on a dark $SU(3)_D$ interaction with three flavors of massless dark…
We show that the mu problem and the strong CP problem can be resolved in the context of the gauged U(1)_R symmetry, realizing an automatic Peccei-Quinn symmetry. In this scheme, right-handed neutrinos can be introduced to explain small…
The axion is arguably one of the best motivated candidates for dark matter. For a decay constant greater than about 10^9 GeV, axions are dominantly produced non-thermally in the early universe and hence are "cold", their velocity dispersion…
Dark matter (DM) and neutrinos are the two most compelling pieces of evidence of new physics beyond the Standard Model of Particle Physics but these are often treated as belonging to two different sectors. Yet DM-neutrino interactions are…
The axion has emerged in recent years as a leading particle candidate to provide the mysterious dark matter in the cosmos, as we review here for a general scientific audience. We describe first the historical roots of the axion in the…
The simplest model that can accomodate a viable nonbaryonic dark matter candidate is the standard electroweak theory with the addition of right-handed or sterile neutrinos. We reexamine this model and find that the sterile neutrinos can be…
The best particle candidates for non--baryonic cold dark matter are reviewed, namely, neutralino, axion, axino and Majoron. These particles are considered in the context of cosmological models with the restrictions given by the observed…
A form of mixing matrix for three active and three sterile, conventional Majorana neutrinos is proposed. Its Majorana lefthanded part arises from the popular bimaximal mixing matrix for three active neutrinos that works satisfactorily in…
Several ideas for new physics beyond the standard model may provide particle candidates for the dark matter in the Galactic halo. The two leading candidates are an axion and a weakly-interacting massive particle (WIMP), such as the…
The smallness of neutrino mass, the strong CP problem, and the existence of dark matter are explained in an economical way. The neutrino mass is generated by the colored version of a radiative seesaw mechanism by using color adjoint…