Showing papers in "Physics of the Dark Universe in 2021"

TL;DR: In this article, the amplitude of the primordial curvature fluctuations is approximately scale-invariant, which implies a multi-modal PBH mass spectrum with peaks at 1 0 − 6, 1, 30, and 1 0 6 M ⊙.

TL;DR: In this article, a black hole with hair represented by generic fields surrounding the central source of the vacuum Schwarzschild metric is examined under the minimal set of requirements consisting of (i) the existence of a well defined event horizon, namely, we require the Killing horizon coincides with the causal horizon and (ii) the strong or dominant energy condition for the hair outside the horizon.

TL;DR: In this paper, the intrinsic curvatures of a hypersurface immersed in the thermodynamic manifold are calculated for a four-dimensional neutral Gauss Bonnet black hole case in the extended phase space, which indicates a repulsive interaction among black hole microstructures.

TL;DR: In this article, the authors used the Baryon Oscillation Spectroscopic Survey DR12 CMASS sample to study the concordance of the CDM cosmological model in light of current observations.

TL;DR: In this article, a new methodology to build up self-gravitating structures driven by an imperfect fluid distribution is presented, which is developed within the framework of f ( R, T ) gravity theory by combining two geometrical schemes, the gravitational decoupling by means of minimal geometric deformation and the embedding technique, specifically the class I grasp.

TL;DR: In this paper, a model-independent reconstruction of the growth history of matter in-homogeneity is studied using Gaussian processes method and the fit yields S 8 = 0. 70 7 − 0. 085 + 0. 0.

TL;DR: In this paper, an analysis dedicated to the dynamical investigation of models of holographic dark energy using FLRW cosmological model in the context of modified gravity in which Lagrangian be the arbitrary function of the trace of the non-metricity tensor Q say f (Q ) gravity where the nonmetricities Q is responsible for the gravitational interaction.

TL;DR: In this article, a theory of gravity combining the gravitation effects through the non-metricity scalar function Q, and manifestations from the quantum era of the Universe in the classical theory was proposed.

TL;DR: In this paper, the authors investigated the shape and size of the observed black hole shadow containing information of the geometry in its vicinity, and thus one can consider it as a potential probe to investigate different gravitational theories, since the involved calculation framework is enriched with different size-rotation features and with extra model parameters.

TL;DR: In this paper, the quasinormal frequencies of the Dirac field for spherically symmetric asymptotically flat black hole in the consistent 4 D EIGA-Gauss-Bonnet theory were calculated using the WKB method with Pade approximants and the time domain integration.

TL;DR: In this article, the implications of a subclass of E -models cosmological attractors, namely of a -attractors, on hydrodynamically stable slowly rotating neutron stars were studied.

TL;DR: In this paper, the spin distributions of LIGO/Virgo black holes from the first catalog GWTC-1 and the first four published binary black hole (BBH) events from run O3 were studied.

TL;DR: In this paper, a timelike particle's periodic orbits around the 4-dimensional Einstein-Lovelock (4 D − EL) black holes are investigated by employing a classification of the zoom-whirl structure with a rational number q.

TL;DR: In this article, the slow-roll approximation of cosmic inflation within the context of f (R, T ) gravity was studied, where R is the scalar curvature, and T is the trace of the energy-momentum tensor.

TL;DR: In this article, a combination of observational data was used to reconstruct the free function of f (T ) gravity in a model-independent manner, which is consistent with the standard Λ CDM cosmology within 1 σ confidence level, however the best-fit value experiences oscillatory features.

TL;DR: The Phenomenologically Emergent Dark Energy model, a dark energy model with the same number of free parameters as the flat Λ CDM, has been proposed as a working example of a minimal model which can avoid the current cosmological tensions as mentioned in this paper.

TL;DR: In this article, a weak field regime was assumed to explore the gravitational lensed photons in a 4 dimensional Einstein-Gauss-Bonnet gravity, which is very much in the limelight these days.

TL;DR: In this paper, a general equation of state is considered for analyzing the possible behaviors for (Early) dark energy that alleviates the Hubble parameter tension problem, which can be considered as a promising starting point to get a better understanding of the cosmological evolution as a whole.

TL;DR: In this article, the authors derived the hydrostatic equilibrium assuming a maximally symmetric phase of homogeneous superconducting quark matter called the color-flavor-locked (CFL) phase in the background of energy-momentum squared gravity (EMSG).

TL;DR: In this paper, the authors investigated the compact anisotropic matter profiles in the context of one of the modified gravitational theories, known as f ( R, T ) gravity, where R is a Ricci Scalar and T is the trace of the energymomentum tensor.

TL;DR: In this paper, the authors derived an analytical formula for the shadow of a rotating Rastall black hole and go on to visualize the shadow for various values of the parameters for an observer at a given coordinates ( r O, θ O ) in the domain [ r +, r q ].

TL;DR: In this article, the cosmological implications of a varying absolute magnitude of Type Ia supernovae using the Pantheon compilation, by reconstructing different phenomenological approaches, such as cosmic voids, modified gravity models and a binning scheme, were investigated.

TL;DR: In this paper, a cosmological model was proposed in which the universe undergoes through a non-singular bounce, and after the bounce, it decelerates having a matter-like dominated evolution during some regime of the deceleration era, and finally at the present epoch it evolves through an accelerating stage.

TL;DR: In this article, a coupled generalized three-form dark energy model was proposed, in which dark energy are represented by a 3-form field and dark matter is represented by point particles that can be regarded as dust.

TL;DR: In this paper, the authors study the anisotropy of quark stars (QSs) assuming the internal composition to be comprised of homogeneous, charge neutral 3-flavor interacting quark matter with O(m s 4 ) corrections.

TL;DR: In this article, the authors present a quantitative estimate of the impact of uncertainties of astrophysical nature on the determination of the dark matter distribution within our Galaxy, the Milky Way, based on an update of a previous analysis, and find that even with these state-of-the-art determination and a range of uncertainties, their impact on searches of physics beyond the standard model stays sizable.

TL;DR: In this article, the authors compute the quasinormal spectra for scalar, Dirac and electromagnetic perturbations of the Schwarzschild-de Sitter geometry in the framework of scale-dependent gravity.

TL;DR: In this paper, the authors proposed five f (Q, T ) models, which are an extension of symmetric teleparallel gravity, where Q is the nonmetricity and T is the trace of the stress energy tensor.

TL;DR: In this paper, the authors inspect the possibility that neutron star interiors are a mixture of ordinary matter and mirror dark matter, and they show that the inclusion of mirror-dark matter in neutron star models lowers the maximum neutron star mass for a given equation of state, and that it decreases the tidal deformability of a given neutron star.