ﻻ يوجد ملخص باللغة العربية
We search for an extension of the Standard Model that contains a viable dark matter candidate and that can be embedded into a fundamental, asymptotically safe, quantum field theory with quantum gravity. Demanding asymptotic safety leads to boundary conditions for the non-gravitational couplings at the Planck scale. For a given dark matter model these translate into constraints on the mass of the dark matter candidate. We derive constraints on the dark matter mass and couplings in two minimal dark matter models: i) scalar dark matter coupled via the Higgs-portal in the $B$-$L$ model; ii) fermionic dark matter in a $U(1)_X$ extension of the Standard Model, coupled via the new gauge boson. For scalar dark matter we find 56 GeV $ < M_text{DM} < 63$ GeV, and for fermionic dark matter $M_text{DM} leq 50$ TeV. Within our framework, we identify three benchmark scenarios with distinct phenomenological consequences.
We propose a new cosmological framework in which the strength of the gravitational force acted on dark matter at late time can be weaker than that on the standard matter fields without introducing extra gravitational degrees of freedom. The framework
We present a model for dark matter with extra spatial dimensions in which Standard-Model (SM) fermions have localized wave functions. The underlying gauge group is $G_{rm SM} otimes {rm U}(1)_z$, and the dark matter particle is a SM-singlet Dirac fer
We consider a simple abelian vector dark matter (DM) model, where {it only} the DM $(widetilde{X}_mu)$ couples non-minimally to the scalar curvature $(widetilde{R})$ of the background spacetime via an operator of the form $sim widetilde{X}_mu,widetil
An unexpected explanation for neutrino mass, Dark Matter (DM) and Dark Energy (DE) from genuine Quantum Chromodynamics (QCD) of the Standard Model (SM) is proposed here, while the strong CP problem is resolved without any need to account for fundamen
A CPT violating decoherence scenario can easily account for all the experimental evidence in the neutrino sector including LSND. In this work it is argued that this framework can also accommodate the Dark Energy content of the Universe, as well as the observed matter-antimatter asymmetry.