相关论文: Parafermionic dark mater
The dark-matter candidates of particle physics invariably possess electromagnetic interactions, if only via quantum fluctuations. Taken en masse, dark matter can thus engender an index of refraction which deviates from its vacuum value. Its…
We propose a new framework for explaining the proximity of the baryon and dark matter relic densities \Omega_{DM} \approx 5\Omega_B. The scenario assumes that the number density of the observed dark matter states is generated due to decays…
Modified gravity can be considered as an alternative to dark energy. In a generalized theory of gravity, the universe may accelerate while containing only baryonic and dark matter. We study, in particular, the evolution of matter…
A fermionic description of dark matter using analogies with nuclear physics is developed. At tree level, scalar and vector processes are considered and the two-body potential are explicitly calculated using the Breit approximation. We show…
Recent cosmological observations, such as the measurement of the primordial 4He abundance, CMB, and large scale structure, give preference to the existence of extra radiation component, Delta N_nu > 0. The extra radiation may be accounted…
The addition of new multiplets of fermions charged under the Standard Model gauge group is investigated, with the aim of identifying a possible dark matter candidate. These fermions are charged under $SU(2)\times U(1)$, and their quantum…
A set of cosmological models that takes into account the variation of the particle number is presented. In this context both dark matter and dark energy can be explained using a single component, without assuming any exotic equation of…
We use the calculations derived in a previous paper (M\'era, Chabrier and Schaeffer, 1997), based on observational constraints arising from star counts, microlensing experiments and kinematic properties, to determine the amount of dark…
The recently observed Deuterium abundance in a low- metallicity high-redshift hydrogen cloud, which is about ten times larger than that observed in the near interstellar medium, is that expected from the Standard Big Bang Nucleosynthesis…
The identity of dark matter is one of the greatest puzzles of our Universe. Its solution may be associated with supersymmetry which is a fundamental space-time symmetry that has not been verified experimentally so far. In many…
Inspired by the excess of gamma rays from the Galactic Center, we confront a number of simplified dark matter models with experimental data. Assuming a single dark matter particle coupled to standard matter via a spin-0 mediator, we compare…
If the next fundamental level of matter occurs (preons) then dark matter must consist of familons containing a "hot" component from massless particles and a "cold" component from massive particles. During evolution of the Universe this dark…
We consider a scenario where a supersymmetric model has multiple dark matter particles. Adding a U(1)' gauge symmetry is a well-motivated extension of the Minimal Supersymmetric Standard Model (MSSM). It can cure the problems of the MSSM…
We propose a simple model in which dark matter particle exchanges mediate a new quantum force between muons and nucleons, resolving the proton charge radius puzzle. At the same time, the discrepancy between the measured anomalous magnetic…
We investigate the relic abundance of asymmetric Dark Matter where the asymmetric Dark Matter is non--thermally produced from the decay of heavier particles in addition to the usual thermal production. We discuss the relic density of…
We discuss a simple model of thermal relic dark matter whose mass can be much larger than the so-called unitarity limit on the mass of point-like particle dark matter. The model consists of new strong dynamics with one flavor of fermions in…
The minimal coupling of massless fermions to gravity does not allow for their gravitational production solely based on the expansion of the Universe. We argue that this changes in presence of realistic and potentially detectable stochastic…
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…
We present a simple mechanism which allows the simultaneous generation of the baryon asymmetry of the Universe along with its dark matter content. To this goal, we employ the out-of-equilibrium decays of heavy bath states into a feebly…
In some baryogenesis scenarios, the universe acquires a non-vanishing average baryonic charge, but the baryon to photon ratio is not spatially constant and can be even negative in some space regions. This allows for existence of lumps of…