Showing papers in "Physics of the Dark Universe in 2016"

TL;DR: In this article, the authors suppress the tails of the point spread function and generate high-resolution gamma-ray maps, enabling them to more easily separate the various gamma ray components, and find the GeV excess to be robust and highly statistically significant, with a spectrum, angular distribution and overall normalization that is in good agreement with that predicted by simple annihilating dark matter models.

TL;DR: There is a persistent interest in extending cosmology beyond the standard model, ΛCDM, motivated by a range of apparently serious theoretical issues, involving such questions as the cosmological constant problem, the particle nature of dark matter, the validity of general relativity on large scales, the existence of anomalies in the CMB and on small scales, and the predictivity and testability of the inflationary paradigm as mentioned in this paper.

TL;DR: In this article, a cosmological upper bound on the sum of active neutrino masses using large-scale power spectrum data from the WiggleZ Dark Energy Survey and from the Sloan Digital Sky Survey - Data Release 7 (SDSS-DR7) sample of Luminous Red Galaxies (LRG) was presented.

TL;DR: In this article, the apparent mass of a neutron star as seen from an observer at infinity is numerically calculable but requires careful matching, first at the star's edge, between interior and exterior solutions, none of them being totally Schwarzschild-like but presenting instead small oscillations of the curvature scalar R ; and second at large radii, where the Newtonian potential is used to identify the mass of the neutron star.

TL;DR: In this article, a study of possible self-interactions of ultralight scalar dark matter from the particle physics point of view is initiated, where the scalar mass is identified as a pseudo Nambu-Goldstone boson (pNGB) to protect its mass.

TL;DR: In this paper, the ultraviolet structure of s-channel mediator simplified models at hadron colliders is considered, and the results are as one would expect: at the LHC and future proton colliders the simplified model descriptions of dark matter production are in general valid.

TL;DR: In this paper, the concept of turnaround radius is extended to modified theories of gravity for which the gravitational slip is nonvanishing, and used in conjunction with observations of large structures to constrain the equation of state of the universe.

TL;DR: In this paper, the authors consider Hořava gravity within the framework of the effective field theory (EFT) of dark energy and modified gravity, and they employ an updated version of the EFTCAMB/EFTCosmoMC package to study the cosmology of the low-energy limit of Hoǫava gravity and place constraints on its parameters.

TL;DR: In this paper, it is shown that the variance smoothed on a local physical scale is not correlated with the large-scale curvature perturbation, so that there is no relativistic signature in the galaxy bias when using the simplest model of bias.

TL;DR: In this article, the collisional dynamics of stable solitary waves in the Schrodinger-Poisson equation were studied in the framework of a model in which part or all of dark matter is a Bose-Einstein condensate of ultralight axions, which can naturally explain the relative displacement between dark and ordinary matter in the galactic cluster Abell 3827.

TL;DR: In this paper, the authors model the effect extending Λ CDM with a scale Δ related to the infrared depression and explore the constraints allowed by Planck 2015 data, employing also more conservative, wider Galactic masks in the low resolution CMB likelihood.

TL;DR: In this paper, the authors investigated cosmological models of the extended Chaplygin gas in a universe governed by Horava-Lifshitz gravity and obtained energy density in terms of scale factor with mentioned free parameters.

TL;DR: In this paper, a variation of light-shining-through-wall (LSW) experiments for axion-like particle searches was proposed, based on very low energy and extremely intense photon sources.

TL;DR: In this paper, the authors explored the sensitivity of the data taken by ADMX from 2008 to 2010 to various dark matter halo models, and showed that certain assumptions about the dark-matter halo improve limits on axion-photon coupling.

TL;DR: The fundamental plane (FP) of galaxies can be recovered in the framework of f (R ) gravity avoiding the issues related to dark matter to fit the observations as mentioned in this paper. But the fundamental plane of galaxies cannot be recovered from the observations.

TL;DR: In this article, the authors explore the possibility to use future extended radio-tracking data from the currently ongoing New Horizons mission in the outskirts peripheries of the Solar System, at about 40 au, to constrain this effective cosmological constant, and thus to impose constrain on each scenario's parameters.

TL;DR: In this article, the authors derived the most general expression for the field excursion in terms of various inflationary observables, applying the observational constraints obtained from recent Planck 2015 and BICEP2/Keck Array data.

TL;DR: In this paper, the authors considered the universe at the late stage of its evolution and deep inside the cell of uniformity and investigated the possibility that the perturbations of DM and DE, which are interacting among themselves, could be coupled to the galaxies with the former being concentrated around them.

TL;DR: In this paper, the first and second laws of black hole thermodynamics are examined at the apparent horizon of FRW spacetime in f ( R, R α β R αβ, ϕ ) gravity, where R, Rαβ Rα β and ϕ are the Ricci invariant, Ricci tensor and the scalar field respectively.

TL;DR: In this paper, the authors proposed that dark energy in the form of a scalar field could effectively couple to dark matter inhomogeneities through the linear growth function of matter perturbations.

TL;DR: In this paper, the authors used the model dependent method to revisit the constraint on the well-known cosmic distance duality relation (CDDR) and found that the SNIa data alone cannot constrain the cosmic opacity parameter e, which denotes the deviation from the CDDR, d L = d A ( 1 + z ) 2 + e, very well.

TL;DR: In this paper, a 14-dimensional parameter space was analyzed for the supernova catalog with a flexible growth-rate index γ and the authors obtained the following marginalized constraints: σ 8 = 0.6 5 − 0.37 + 0.23 + 1.7.

TL;DR: In this paper, the authors proposed a new scenario for the onset of positive acceleration of our universe based on symmetry breaking in coupled dark energy scalar field model and showed that this procedure may establish the positivity of the potential required for the Universe to accelerate.

TL;DR: In this paper, the gravitino dark matter of bilinear R-parity violating supersymmetric models was used as a source of high energy electrons and positrons.

TL;DR: In this article, a model of modified gravity from the nonperturbative quantization of a metric was considered and applied to the FLRW spacetime and found that due to the quantum fluctuations a bounce universe can be obtained and a decelerated expansion can also possibly be obtained in a dark energy dominated epoch.

TL;DR: In this paper, the authors use the ACTpol published cosmic microwave background (CMB) polarization data to constrain cosmological birefringence, a tracer of parity violation beyond the standard model of particle physics.

TL;DR: In this paper, the dynamics of scalar metric fluctuations in a nonperturbative variational formalism were studied in the framework of inflationary cosmology. And the resulting spectral predictions were in very good agreement with observations and other models of inflation.

TL;DR: In this paper, a generalization of teleparallel gravity is presented that is consistent with local spacetime kinematics regulated by the de Sitter group S O ( 1, 4 ).

TL;DR: In this article, the authors explore the merit of the Hubble parameter data and make an attempt to reconstruct the dark energy equation of state parameter w ( z ) from them through the principle component analysis approach.

TL;DR: In this article, the authors study cosmological dynamics of an extended gravitational theory that gravity is coupled non-minimally with derivatives of a dark energy component and there is also a phenomenological interaction between the dark energy and dark matter.