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Related papers: Rendering Dark Energy Void

200 papers

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

A family of simple and minimal extensions of the standard cosmological $\Lambda$CDM model in which dark matter experiences an additional long-range scalar interaction is demonstrated to alleviate the long lasting Hubble-tension while…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-08 Jean-Philippe Uzan , Cyril Pitrou

The dark energy problem has led to speculation that not only may LCDM be wrong, but that the FLRW models themselves may not even provide the correct family of background models. We discuss how direct measurements of H(z) can be used to…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-12 Arman Shafieloo , Chris Clarkson

The apparent accelerating expansion of the Universe is forcing us to examine the foundational aspects of the standard model of cosmology -- in particular, the fact that dark energy is a direct consequence of the homogeneity assumption. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Chris Clarkson , Roy Maartens

The considerable difference between early and late universe measurements of the Hubble constant, called the Hubble tension, poses a potential challenge to the standard $\Lambda$CDM cosmological model. We examine an interacting dark…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-11 Yismaw Wassie Ambelu , Amare Abebe , Solomon Belay Tessema , Shambel Sahlu

The disagreement between direct late-time measurements of the Hubble constant from the SH0ES collaboration, and early-universe measurements based on the $\Lambda$CDM model from the Planck collaboration might, at least in principle, be…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-02 Guido D'Amico , Leonardo Senatore , Pierre Zhang , Henry Zheng

For the first time, we reconstruct the dark energy equation of the state parameter $w$ from the combination of background and perturbation observations, specifically combining the Hubble parameter data from cosmic chronometer observations…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-15 Bikash R. Dinda , Narayan Banerjee

Within the frame of the $\Lambda$ cold dark matter paradigm, a dark energy component of unknown origin is expected to represent nearly 70% of the energy of the Universe. Herein, a non-standard form of the Hubble law is advocated, with the…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-12 Yves-Henri Sanejouand

There has been considerable interest in recent years in cosmological models in which we inhabit a very large, underdense void as an alternative to dark energy. A longstanding objection to this proposal is that observations limit our…

Cosmology and Nongalactic Astrophysics · Physics 2010-12-23 Simon Foreman , Adam Moss , James P. Zibin , Douglas Scott

We show that quantum decoherence, in the context of observational cosmology, can be connected to the cosmic dark energy. The decoherence signature could be characterized by the existence of quantum entanglement between cosmological eras. As…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Salvatore Capozziello , Orlando Luongo

We consider holographic cosmological models of dark energy in which the infrared cutoff is set by the Hubble's radius. We show that any interacting dark energy model with a matter like term able to alleviate the coincidence problem (i.e.,…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-03 Iván Durán , Luca Parisi

Decaying dark matter models generically modify the equation of state around the time of dark matter decay, and this in turn modifies the expansion rate of the Universe through the Friedmann equation. Thus, a priori, these models could solve…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-04 Andreas Nygaard , Emil Brinch Holm , Thomas Tram , Steen Hannestad

In this work, we investigate the phenomenologically emergent dark energy (PEDE) model and its generalized form, namely the generalized emergent dark energy (GEDE) model, which introduces a free parameter \unboldmath {\( \Delta \)} that can…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-25 GuangZhen Wang , Xiaolei Li , Nan Liang

The Hubble constant is one of the most important parameters in cosmology. Discrepancies in values of the Hubble constant estimated from various measurements, the so-called Hubble tension, are a serious problem. In this paper, we study the…

General Relativity and Quantum Cosmology · Physics 2025-02-03 Taishi Miura , Takahiro Tanaka

We investigate the effect that the average backreaction of structure formation has on the dynamics of the cosmological expansion, within the concordance model. Our approach in the Poisson gauge is fully consistent up to second-order in a…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 Chris Clarkson , Kishore Ananda , Julien Larena

Using cosmic voids to probe the growth rate of cosmic structure, and hence the nature of dark energy, is particularly interesting in the context of modified gravity theories that rely on the screening mechanism. In this work we improve the…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-11 Ixandra Achitouv

We study dark energy through the viewpoints of parametric and nonparametric analyses of late-time cosmological data. We consider four Hubble parameter priors reflecting the Hubble tension and make use of two phenomenological functions,…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Reginald Christian Bernardo , Daniela Grandón , Jackson Levi Said , Víctor H. Cárdenas

In this paper, we give a conceptual explanation of dark energy as a small negative residual scalar curvature present even in empty spacetime. This curvature ultimately results from postulating a discrete spacetime geometry, very closely…

Mathematical Physics · Physics 2012-08-16 Aaron Trout

We investigate the dark energy phenomenology in an extended parameter space where we allow the curvature density of our universe as a free-to-vary parameter. The inclusion of the curvature density parameter is motivated from the recently…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-29 Mehdi Rezaei , Supriya Pan , Weiqiang Yang , David F. Mota

I briefly outline a new physical interpretation to the average cosmological parameters for an inhomogeneous universe with backreaction. The variance in local geometry and gravitational energy between ideal isotropic observers in bound…

Cosmology and Nongalactic Astrophysics · Physics 2009-12-31 David L. Wiltshire