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Related papers: Dark energy as a mirage

200 papers

Within the context of standard cosmology, an accelerating universe requires the presence of a third `dark' component of energy, beyond matter and radiation. The available data, however, are still deemed insufficient to distinguish between…

Astrophysics · Physics 2009-08-25 Fulvio Melia

We show that there is no need for the hypothetical Dark Energy (DE) and Dark Matter (DM) to explain phenomena attributed to them. In contrast to the consensus of the last decade, we show that the time derivative of the cosmological scale…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-15 Shlomo Barak , Elia M Leibowitz

We construct a cosmological model which is physically reasonable, mathematically tractable, and extends the study of CDM models to the case where the equations of state (EoS) for matter and dark energy (DE) vary with time. It is based on…

General Relativity and Quantum Cosmology · Physics 2012-06-14 J. Ponce de Leon

The main argument that Universe is currently expanding is observed redshift increase by distance. However, this conclusion may not be correct, because cosmological redshift depends only on the scaling factors, the change in the size of the…

General Physics · Physics 2012-07-05 Branislav Vlahovic

Several models have been proposed to explain the dark energy that is causing universe expansion to accelerate. Here the acceleration predicted by the Holographic Dark Information Energy (HDIE) model is compared to the acceleration that…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Michael Paul Gough

We present empirical evidence extracted directly from the Pantheon Catalog of SNeIa demonstrating that the speed of light varies as the universe expands. Moreover, the speed of light must vary in a specific quantifiable manner. To show…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-10 Hoang Ky Nguyen

As an explanation for the acceleration of the universe, we propose dark matter with self-interactions characterized by a negative pressure; there is no vacuum energy whatsoever in this Cardassian model. These self-interactions may arise due…

High Energy Physics - Phenomenology · Physics 2007-05-23 Paolo Gondolo , Katherine Freese

We present a systematic exploration of dark energy and modified gravity models containing a single scalar field non-minimally coupled to the metric. Even though the parameter space is large, by exploiting an effective field theory (EFT)…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-03 Louis Perenon , Federico Piazza , Christian Marinoni , Lam Hui

We present an impact of coupling between dark matter and a scalar field, which might be responsible for dark energy, on measurements of redshift-space distortions. We point out that, in the presence of conformal and/or disformal coupling,…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-22 Rampei Kimura , Teruaki Suyama , Masahide Yamaguchi , Daisuke Yamauchi , Shuichiro Yokoyama

We develop a cosmological model based on action-dependent Lagrangian theories. The main feature here is the nonconservation of the energy momentum tensor due to the nontrivial geometrical construction of the theory. We provide the basic set…

General Relativity and Quantum Cosmology · Physics 2018-11-05 Thiago R. P. Caramês , H. Velten , J. C. Fabris , Matheus J. Lazo

A web of interlocking observations has established that the expansion of the Universe is speeding up and not slowing, revealing the presence of some form of repulsive gravity. Within the context of general relativity the cause of cosmic…

Astrophysics · Physics 2008-11-26 Michael S. Turner , Dragan Huterer

We examine the cosmological implications of measurements of the void-galaxy cross-correlation at redshift $z=0.57$ combined with baryon acoustic oscillation (BAO) data at $0.1<z<2.4$. We find direct evidence of the late-time acceleration…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-01 Seshadri Nadathur , Will J. Percival , Florian Beutler , Hans Winther

Cosmological observations strongly suggest the presence of dark energy which comprises the majority of the current energy density of the universe. The equation of state relating the pressure and energy density of this dark energy, p = w…

Astrophysics · Physics 2007-05-23 Eric Gawiser

Current observational bounds on dark energy depend on assumptions about the curvature of the universe. We present a simple and efficient method for incorporating constraints from CMB anisotropy data, and use it to derive constraints on…

Astrophysics · Physics 2010-04-06 Yun Wang , Pia Mukherjee

The recently observed Deuterium abundance in a low- metallicity high-redshift hydrogen cloud, which is about ten times larger than that observed in the near interstellar medium, is that expected from the Standard Big Bang Nucleosynthesis…

Astrophysics · Physics 2009-10-28 Arnon Dar

In the last dozens of years different data sets revealed the accelerated expansion of the Universe which is driven by the so called dark energy, that now dominates the total amount of matter-energy in the Universe. In a recent paper Glavan,…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-27 Marek Demianski , Ester Piedipalumbo

With the next generation of big telescopes such as the ELT and SKA it might become possible to measure changes in the expansion rate of the Universe in real time by measuring the change of the redshifts of a large number of galaxies over a…

Cosmology and Nongalactic Astrophysics · Physics 2025-12-02 Nico Roos , Eric Sluimer , Bert van den Broek

We present a comparison of void properties between the standard model of cosmology, $\Lambda$ Cold Dark Matter ($\Lambda$CDM), and two alternative cosmological models with evolving and interacting dark sectors: a quintessence model…

Cosmology and Nongalactic Astrophysics · Physics 2017-05-03 Eromanga Adermann , Pascal J. Elahi , Geraint F. Lewis , Chris Power

Exclusion zones in the cross-correlations between critical points (peak-void, peak-wall, filament-wall, filament-void) of the density field define quasi-standard rulers that can be used to constrain dark matter and dark energy cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-19 Junsup Shim , Christophe Pichon , Dmitri Pogosyan , Stephen Appleby , Corentin Cadiou , Juhan Kim , Katarina Kraljic , Changbom Park

We combine the latest observationally motivated constraints on stellar properties in dark matter haloes, along with data-driven predictions for the atomic (HI) and molecular (H$_2$) gas evolution in galaxies, to derive empirical…

Astrophysics of Galaxies · Physics 2020-06-10 Hamsa Padmanabhan , Abraham Loeb