English
Related papers

Related papers: Observational constraints on unified dark matter i…

200 papers

In this Comment we discuss a recent analysis by Yu et al. [RAA 11, 125 (2011)] about constraints on the smoothness $\alpha$ parameter and dark energy models using observational $H(z)$ data. It is argued here that their procedure is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 V. C. Busti , R. C. Santos

In this work, we impose observational limits on the product of dark energy chemical potential, $\mu$, and number density, $n$, at the present time in out-of-equilibrium models, considering that particles can be created or destroyed in the…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-21 J. M. Costa Netto , Javier E. Gonzalez , H. H. B. Silva

In this paper, a unified dark fluid with constant adiabatic sound speed is decomposed into cold dark matter interacting with vacuum energy. Based on Markov chain Monte Carlo method, we constrain this model by jointing the geometry and…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-18 Weiqiang Yang , Lixin Xu , Yuting Wang , Yabo Wu

The unified dark fluid model unifies dark matter and dark energy into a single component, providing an alternative and more concise framework for interpreting cosmological observations. We introduce a PAge-like Unified Dark Fluid (PUDF)…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-06 Junchao Wang , Zhiqi Huang , Yanhong Yao , Jianqi Liu , Lu Huang , Yan Su

When Cold Dark Matter (CDM) power spectrum normalized by COBE results, its amplitude at smaller scales can be parametrized by $\Gamma\sim\Omega_0h$. The expected variations of Hubble flows in two samples, the sample of 36 clusters in the…

Astrophysics · Physics 2016-01-13 Xiangdong Shi

We revisit cosmological neutrino mass bounds when a fraction of dark matter is allowed to decay to massless dark radiation. By compensating the late-time increase in the matter density induced by neutrinos becoming non-relativistic,…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-04 Thomas Montandon , Vivian Poulin , Thomas Rink , Thomas Schwetz

Observational growth rate data had been derived from observations of redshift distortions in galaxy redshift surveys. Here we use the growth rate data to place constraints on the dark energy model parameters. By performing a joint analysis…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 K. Shi , Y. F. Huang , T. Lu

We improve the earlier restrictions on parameters of the dark matter (DM) in the form of a sterile neutrino. The results were obtained from non-observing the DM decay line in the X-ray spectrum of the Milky Way (using the recent XMM-Newton…

Astrophysics · Physics 2008-11-26 Alexey Boyarsky , Jukka Nevalainen , Oleg Ruchayskiy

Decaying dark matter models provide a physically motivated way of channeling energy between the matter and radiation sectors. In principle, this could affect the predicted value of the Hubble constant in such a way as to accommodate the…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-04 Emil Brinch Holm , Thomas Tram , Steen Hannestad

While cold dark matter is widely supported by a range of cosmological observations, it encounters several difficulties at smaller scales. These issues have prompted the investigation of various alternative dark matter candidates, leaving…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-23 Jian-Qi Liu , Yan-Hong Yao , Yan Su , Jia-Wei Wu

In this paper, we set the new limits on the equation of state parameter (EoS) of dark energy with the observations of cosmic microwave background radiation (CMB) from Planck satellite, the type Ia supernovae from Pan-STARRS and the baryon…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-15 Wei Zheng , Si-Yu Li , Hong Li , Jun-Qing Xia , Mingzhe Li , Tan Lu

We investigate Kaniadakis-holographic dark energy by confronting it with observations. We perform a Markov Chain Monte Carlo analysis using cosmic chronometers, supernovae type Ia, and Baryon Acoustic Oscillations data. Concerning the…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 A. Hernández-Almada , Genly Leon , Juan Magaña , Miguel A. García-Aspeitia , V. Motta , Emmanuel N. Saridakis , Kuralay Yesmakhanova

We examine the decay vacuum model with a parameter $\epsilon$ that indicates the vacuum energy decay rate. By constraining this model with cosmic microwave background radiation, baryon acoustic oscillation, type Ia supernovae and 30 H(z)…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-04 Yang-Jie Yan , Deng Wang , Xin-He Meng

Dark energy and dark matter constitute 95% of the observable Universe. Yet the physical nature of these two phenomena remains a mystery. Einstein suggested a long-forgotten solution: gravitationally repulsive negative masses, which drive…

General Physics · Physics 2018-12-05 J. S. Farnes

We consider a phenomenological model for a coupling between the dark matter and dark energy fluids and investigate the sensitivity of a weak lensing measurement for constraining the size of this coupling term. Physically, the functional…

We consider cosmic chronometer (CC) data for the Hubble parameter, quasar (QSO) luminosities data of X-rays and ultraviolet rays emission, and the latest measurements of the present value of the Hubble parameter from 2018 Planck mission…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-29 Bikash R. Dinda , Haveesh Singirikonda , Subhabrata Majumdar

We investigate observational constraints on the curvature of the universe not restricting ourselves to a cosmological constant as dark energy, in particular allowing a dark energy equation of state to evolve with time in several ways. We…

Astrophysics · Physics 2010-10-27 Kazuhide Ichikawa , Tomo Takahashi

A new method to investigate a possible time-dependence of the dark energy equation of state $w$ is proposed. We apply this methodology to two of the most recent data sets of type Ia supernova (Union2 and SDSS) and the baryon acoustic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 E. M. Barboza , J. S. Alcaniz

We use observational data from Supernovae (SNIa) Pantheon sample, as well as from direct measurements of the Hubble parameter from the cosmic chronometers (CC) sample, in order to extract constraints on the scenario of Barrow holographic…

General Relativity and Quantum Cosmology · Physics 2020-06-25 Fotios K. Anagnostopoulos , Spyros Basilakos , Emmanuel N. Saridakis
‹ Prev 1 8 9 10 Next ›