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Related papers: Can we avoid dark energy?

200 papers

Primordially formed extended dark objects would accrete baryonic matter and impact the ionisation history of the Universe. Insisting on consistency with the anisotropies of the cosmic microwave background, we derive constraints on the dark…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-01 Djuna Croon , Sergio Sevillano Muñoz

We propose a cosmological model that makes a significant step toward solving the coincidence problem of the near similarity at the present of the dark energy and dark matter components. Our cosmology has the following properties: a) among…

Astrophysics · Physics 2008-11-26 Luca Amendola , Domenico Tocchini-Valentini

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

The acceleration of the universe can be explained either through dark energy or through the modification of gravity on large scales. In this paper we investigate modified gravity models and compare their observable predictions with dark…

Astrophysics · Physics 2008-11-26 Edmund Bertschinger , Phillip Zukin

In this paper we consider the effects of adding curvature in extended cosmologies involving a free-to-vary neutrino sector and different parametrizations of Dark Energy (DE). We make use of the Planck 2018 cosmic microwave background…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-29 Weiqiang Yang , William Giarè , Supriya Pan , Eleonora Di Valentino , Alessandro Melchiorri , Joseph Silk

Void models provide a possible explanation of the "accelerated expansion" of the Universe without dark energy. To make the conventional void models more realistic, we allow the void, an underdense region around us, to be anisotropic and…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-29 Masayuki Tanimoto , Yasusada Nambu , Kazuhiro Iwata

In this mini-review we discuss first why we should investigate cosmological models beyond LCDM. We then show how to describe dark energy or modified gravity models in a fluid language with the help of one background and two perturbation…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-24 Martin Kunz

For the first time, we have a plausible, complete accounting of matter and energy in the Universe. Expressed a fraction of the critical density it goes like this: neutrinos, between 0.3% and 15%; stars, 0.5%; baryons (total), 5%; matter…

Astrophysics · Physics 2007-05-23 Michael S. Turner

We discuss the systematic uncertainties in the recovery of dark energy properties from the use of baryon acoustic oscillations as a standard ruler. We demonstrate that while unknown relativistic components in the universe prior to…

Astrophysics · Physics 2008-11-26 Daniel J. Eisenstein , Martin White

A huge amount of good quality data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision Cosmology. Despite…

General Relativity and Quantum Cosmology · Physics 2008-12-02 S. Capozziello

In the proposed model with interaction between dark energy and dark matter, we consider cosmological scenarios with different equations of state ($w_d$) for dark energy. For both constant and variable equation of state, we analyze solutions…

General Relativity and Quantum Cosmology · Physics 2017-10-18 Supriya Pan , German S. Sharov

To investigate whether the dark energy evolves over time, we propose two null tests and constrain them using the data combination of cosmic microwave background radiation, baryonic acoustic oscillations, Type Ia supernovae, Planck-2015…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-22 Deng Wang , Xin-He Meng

In this work, we demonstrate that a dynamical dark energy component predicted by massive gravity gives rise to a distinctive evolution of the equation of state. This scenario is favoured over the standard $\Lambda$CDM model when confronted…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-27 Juri Smirnov

We investigate the clustering properties of dynamical Dark Energy even in association of a possible coupling between Dark Energy and Dark Matter. We find that within matter inhomogeneities, Dark Energy migth form voids as well as…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-09 Roberto Mainini

A huge amount of good quality astrophysical data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision…

Astrophysics · Physics 2009-06-23 S. Capozziello

It is now, generally, believed that the presence of some form of dark matter is essential to explain the flat rotation curves of galaxies, and anomalous large velocities of galaxies in the clusters and superclusters. This dark matter turns…

Astrophysics · Physics 2007-05-23 Mofazzal Azam

We show the importance of properly including the perturbations of the dark energy component in the dynamical dark energy models based on a scalar field and modified gravity theories in order to meet with present and future observational…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-29 Chan-Gyung Park , Jai-chan Hwang , Jae-heon Lee , Hyerim Noh

We use Pantheon Type Ia supernova (SN Ia) apparent magnitude, DES-3yr binned SN Ia apparent magnitude, Hubble parameter, and baryon acoustic oscillation measurements to constrain six spatially flat and non-flat cosmological models. These…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-21 Shulei Cao , Joseph Ryan , Bharat Ratra

We forecast the sensitivity of thirty-five different combinations of future Cosmic Microwave Background and Large Scale Structure data sets to cosmological parameters and to the total neutrino mass. We work under conservative assumptions…

Cosmology and Nongalactic Astrophysics · Physics 2019-05-08 Thejs Brinckmann , Deanna C. Hooper , Maria Archidiacono , Julien Lesgourgues , Tim Sprenger

The exact nature of dark energy is currently unknown and its cosmological perturbations, when dark energy is assumed not to be the cosmological constant, are usually modeled as adiabatic. Here we explore the possibility that dark energy…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-23 Rubén Arjona , Juan García-Bellido , Savvas Nesseris