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Related papers: Constraining Logotropic Unified Dark Energy Models

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We perform a detailed confrontation of various oscillating dark-energy parame-trizations with the latest sets of observational data. In particular, we use data from Joint Light Curve analysis (JLA) sample from Supernoave Type Ia, Baryon…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-19 Supriya Pan , Emmanuel N. Saridakis , Weiqiang Yang

From observations at low and high redshifts, it is well known that the bulk of dark matter (DM) has to be stable or at least very long-lived. However, the possibility that a small fraction of DM is unstable or that all DM decays with a…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-19 Jozef Bucko , Sambit K. Giri , Aurel Schneider

We investigate the accuracy attainable by forthcoming space-based observations of the cosmic microwave background (CMB) temperature and polarization anisotropy in constraining the dark energy density parameter $\Oq$ and equation of state…

Astrophysics · Physics 2009-11-07 A. Balbi , C. Baccigalupi , F. Perrotta , S. Matarrese , N. Vittorio

In this work, we investigate the constraints on the total neutrino mass in the scenario of vacuum energy interacting with cold dark matter (abbreviated as I$\Lambda$CDM) by using the latest cosmological observations. We consider four…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-16 Hai-Li Li , Jing-Fei Zhang , Xin Zhang

We investigate a phenomenological extension of the standard $\Lambda$CDM framework, the $\Omega_1\Omega_2$-$\Lambda$CDM model, in which the total energy density of the universe is expanded in powers of $1+z$. This parameterization recovers…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-20 Suresh Kumar

We present constraints on extensions to the flat $\Lambda$CDM cosmological model by varying the spatial curvature $\Omega_K$, the sum of the neutrino masses $\sum m_\nu$, the dark energy equation of state parameter $w$, and the Hu-Sawicki…

The paper brings a novel approach to unification of dark matter and dark energy in terms of a cosmic fluid. A model is introduced in which the cosmic fluid speed of sound squared is defined as a function of its equation of state (EoS)…

General Relativity and Quantum Cosmology · Physics 2019-08-06 Dalibor Perkovic , Hrvoje Stefancic

We present a best-fit analysis on the single-parameter holographic dark energy model characterized by the conformal-age-like length, $L=\frac{1}{a^4(t)}\int_0^tdt' a^3(t') $. Based on the Union2 compilation of 557 supernova Ia data, the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Zhuo-Peng Huang , Yue-Liang Wu

The cosmological constant $\Lambda$ and cold dark matter (CDM) model ($\Lambda\text{CDM}$) is one of the pillars of modern cosmology and is widely used as the de facto theoretical model by current and forthcoming surveys. As the nature of…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-08 Rubén Arjona , Alessandro Melchiorri , Savvas Nesseris

Early dark energy models, for which the contribution to the dark energy density at high redshifts is not negligible, influence the growth of cosmic structures and could leave observable signatures that are different from the standard…

Cosmology and Nongalactic Astrophysics · Physics 2009-04-01 Jun-Qing Xia , Matteo Viel

There is mounting evidence from multiple cosmological probes that dark energy may be dynamical, with an equation of state that evolves over cosmic time. While this evidence is typically quantified using the Chevallier-Polarski-Linder (CPL)…

Cosmology and Nongalactic Astrophysics · Physics 2025-04-02 Daniel A. Kessler , Luis A. Escamilla , Supriya Pan , Eleonora Di Valentino

Knowing the late time evolution of the Universe and finding out the causes for this evolution are the important challenges of modern cosmology. In this work, we adopt a model-independent cosmographic approach and approximate the Hubble…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-23 Salvatore Capozziello , Ruchika , Anjan A Sen

We study spatially-flat dynamical dark energy parametrizations, $w(z)$CDM, with redshift-dependent dark energy equation of state parameter $w(z)$ expressed using three different quadratic and other polynomial forms (as functions of $1-a$,…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-03 Chan-Gyung Park , Bharat Ratra

We study the observational constraints of CMB temperature and polarization anisotropies on models of dark energy, with special focus on models with variation in properties of dark energy with time. We demonstrate that the key constraint…

Astrophysics · Physics 2014-10-13 H. K. Jassal , J. S. Bagla , T. Padmanabhan

We present cosmological parameters measurements from the full combination of DESI DR1 galaxy clustering data described with large-scale structure effective field theory. By incorporating additional datasets (photometric galaxies and CMB…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-23 Mikhail M. Ivanov , James M. Sullivan , Shi-Fan Chen , Anton Chudaykin , Mark Maus , Oliver H. E. Philcox

Recent results from the DESI collaboration suggest a preference for an evolving dark energy (DE) component rather than a cosmological constant, motivating the exploration of alternative models for the background expansion. These data also…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-19 Mario A. Rodríguez-Meza , Jorge L. Cervantes-Cota , Tonatiuh Matos

It has been theorized that Dynamical Dark Energy (DDE) could be a possible solution to the Hubble tension. To avoid the degeneracy between the Hubble parameter $H_0$ and the sound horizon scale $r_d$, in this article we use their…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-02 Denitsa Staicova

In order to explain the current acceleration of the Universe, the fine tuning problem of the cosmological constant $\Lambda$ and the cosmic coincidence problem, different alternative models have been proposed in the literature. We use the…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-13 Alexander Bonilla Rivera , Jorge García Farieta

We here propose a new class of barotropic factor for matter, motivated by properties of isotropic deformations of crystalline solids. Our approach is dubbed Anton-Schmidt's equation of state and provides a non-vanishing, albeit small,…

General Relativity and Quantum Cosmology · Physics 2017-12-13 Salvatore Capozziello , Rocco D'Agostino , Orlando Luongo

We consider the possibility that the universe is made of a single dark fluid described by a logotropic equation of state $P=A\ln(\rho/\rho_*)$, where $\rho$ is the rest-mass density, $\rho_*$ is a reference density, and $A$ is the…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-29 Pierre-Henri Chavanis
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