Related papers: Cosmic microwave background constraints on extende…
The majoron provides an attractive dark matter candidate, directly associated to the mechanism responsible for spontaneous neutrino mass generation within the standard model framework. Here we update the cosmological and astrophysical…
We use the latest cosmic microwave background (CMB) observations to provide updated constraints on the dark matter lifetime as well as on p-wave suppressed annihilation cross sections in the 1 MeV to 1 TeV mass range. In contrast to…
The cosmic microwave background temperature is a cornerstone astrophysical observable. Its present value is tightly constrained, but its redshift dependence, which can now be determined until redshift $z\sim6.34$, is also an important probe…
In the standard theory of the large scale structure formation, matter accretes onto high density perturbations via gravitational instability. Collisionless dark matter forms caustics around such structures, while collisional baryonic matter…
Light dark matter annihilating into electron-positron pairs emits a significant amount of internal bremsstrahlung that may contribute to the cosmic gamma-ray background. The amount of emitted gamma-rays depends on the dark matter clumping…
In the first part of this work, I review the theoretical framework of cosmological perturbation theory necessary to understand the generation and evolution of cosmic microwave background (CMB) anisotropies. Using analytical and numerical…
The cosmic microwave background (CMB) contains perturbations that are close to Gaussian and isotropic. This means that its information content, in the sense of the ability to constrain cosmological models, is closely related to the number…
We investigate the cosmological stability of light bosonic dark matter carrying a tiny electric charge. In the wave-like regime of high occupation numbers, annihilation into gauge bosons can be drastically enhanced by parametric resonance.…
The detectability of light dark matter in direct detection experiments is limited by the small kinetic energy of the recoiling targets. Thus, scenarios where dark matter is boosted to relativistic velocities provide a useful tactic to…
Stellar-mass Primordial Black Holes (PBH) have been recently reconsidered as a Dark Matter (DM) candidate, after the aLIGO discovery of several binary BH mergers with masses of tens of $M_\odot$. Matter accretion on such massive objects…
Using an approximate likelihood method adapted to band--power estimates, we analyze the ensemble of first generation cosmic microwave background anisotropy experiments to deduce constraints over a six--dimensional parameter space describing…
We obtain very stringent bounds on the possible cold dark matter, baryon and neutrino isocurvature contributions to the primordial fluctuations in the Universe, using recent cosmic microwave background and large scale structure data. In…
Primordial black holes (PBHs) of stellar mass or heavier would accrete baryonic gas, which becomes denser and hotter, injecting energetic photons in the cosmological medium soon after cosmic recombination, in the so-called dark ages. The…
We propose to use a simple observable, the fractional area of "hot spots" in weak gravitational lensing mass maps which are detected with high significance, to determine background cosmological parameters. Because these high-convergence…
We consider a cosmology in which a spherically symmetric large scale inhomogeneous enhancement or a void are described by an inhomogeneous metric and Einstein's gravitational equations. For a flat matter dominated universe the inhomogeneous…
The anisotropy of the cosmic microwave background radiation contains information about the contents and history of the universe. We report new limits on cosmological parameters derived from the angular power spectrum measured in the first…
Wave-like dark matter may feature quadratic couplings to ordinary matter. This carries profound consequences for the phenomenologies of such models. It changes the dark matter density around dense objects made from ordinary matter such as…
We discuss the cosmological evolution of matter sources with small anisotropic pressures. This includes electric and magnetic fields, collisionless relativistic particles, gravitons, antisymmetric axion fields in low-energy string…
Current evidence for dark matter in the universe does not exclude heavy composite nuclear-density objects consisting of bound quarks or antiquarks over a significant range of masses. Here we analyze one such proposed scenario, which…
Dark matter in the cosmological concordance model is parameterised by a single number, describing the covariantly conserved energy density of a non-relativistic fluid. Here we test this assumption in a model-independent and conservative way…