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Related papers: Observational challenges in dark energy models

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Under the assumption that they are standard(isable) candles, the lightcurves of Type Ia supernovae have been analyzed in the framework of the standard Friedmann-Lema\^itre-Robertson-Walker cosmology to conclude that the expansion rate of…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-14 Mohamed Rameez

Type Ia Supernovae hold great promise to measure the cosmic deceleration. The diversity observed among these explosions, however, complicates their ability to measure cosmological parameters considerably. The comparison of near and distant…

Astrophysics · Physics 2007-05-23 B. Leibundgut

Measurements of the current expansion rate of the Universe, $H_0$, using standard candles, disagree with those derived from observations of the Cosmic Microwave Background (CMB). This discrepancy, known as the Hubble tension, is substantial…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-05 Sergio Torres-Arzayus

A new cosmological model has been developed that shows great promise for solving many of the present problems of physics. A new concept of space and its production, spatial condensation (SC) is the cause of the expansion. Dark mass (not…

Astrophysics · Physics 2007-05-23 Charles B. Leffert

The good agreement between large-scale observations and the predictions of the now-standard $\Lambda$CDM theory gives us hope that this will become a lasting foundation for cosmology. After briefly reviewing the current status of the key…

Astrophysics · Physics 2011-08-23 Joel R. Primack

Widening cracks are appearing in the $\Lambda$CDM model and it is becoming increasingly clear that the standard cosmological model struggles to describe the full expansion history of the Universe as revealed by the Cosmic Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-03 Alexie Leauthaud , Adam Riess

In this paper, we present a scheme to investigate the opacity of the Universe in a cosmological-model-independent way, with the combination of current and future measurements of type Ia supernova sample and galactic-scale strong…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Yu-Bo Ma , Shuo Cao , Jia Zhang , Jingzhao Qi , Tonghua Liu , Yuting Liu , Shuaibo Geng

The universe with adiabatic matter creation is considered. It is thought that the negative pressure caused by matter creation can play the role of a dark energy component, and drive the accelerating expansion of the universe. Using the Type…

Astrophysics · Physics 2015-06-24 Yuan Qiang , Tong-Jie Zhang , Ze-Long Yi

We use current measurements of the expansion rate $H(z)$ and cosmic background radiation bounds on the spatial curvature of the Universe to impose cosmological model-independent constraints on cosmic opacity. To perform our analyses, we…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 R. F. L. Holanda , J. C. Carvalho , J. S. Alcaniz

In the standard model of cosmology, dark matter and dark energy are presently the two main contributors to the total energy in the Universe. However, these two dark components are still of unknown nature, and many alternative explanations…

Astrophysics · Physics 2009-06-25 A. Arbey

The current expansion of the Universe has been observed to be accelerating, and the widely accepted spatially-flat concordance model of general relativistic cosmology attributes this phenomenon to a constant dark energy, a cosmological…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-13 Shulei Cao

Supernovae Ia (SNe Ia) light curves have been used to prove the universe is expanding. As standard candles, SNe Ia appear to indicate the rate of expansion has increased in the past and is now decreasing. This independent evaluation of SNe…

Astrophysics · Physics 2007-05-23 Jerry W. Jensen

The cause for the observed acceleration in the expansion of the universe is unknown, and referred to as "dark energy" for convenience. Dark energy could be an unknown energy component, or a modification of Einstein's general relativity.…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Yun Wang

The observed late-time acceleration of the cosmic expansion constitutes a fundamental problem in modern theoretical physics and cosmology. In an attempt to weight the validity of a large number of dark energy models, I use the recent…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-21 Spyros Basilakos

Recently, few cosmological models with additional non-Riemannian volume form(s) have been proposed. In this article we use Supernovae type Ia experimental data to test one of these models which provides a unified description of both dark…

General Relativity and Quantum Cosmology · Physics 2018-10-05 Denitsa Staicova , Michail Stoilov

We focus on uncertainties in supernova measurements, in particular of individual magnitudes and redshifts, to review to what extent supernovae measurements of the expansion history of the universe are likely to allow us to constrain a…

Astrophysics · Physics 2011-05-12 Lawrence M. Krauss , Katherine Jones-Smith , Dragan Huterer

Observations of distant type Ia supernovae (SNe Ia), used as standard candles, support the notion that the Cosmos is filled with a mysterious form of energy, the dark energy. The constraints on cosmological parameters derived from data of…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-29 A. Feoli , L. Mancini , V. Rillo , M. Grasso

Evidence for an accelerated expansion of the universe as it has been revealed ten years ago by the Hubble diagram of distant type Ia supernovae represents one of the major modern revolutions for fundamental physics and cosmology. It is yet…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Alain Blanchard

By using the Sloan Digital Sky Survey (SDSS) first year type Ia supernova (SN Ia) compilation, we compare two different approaches (traditional \chi^2 and complete likelihood) to determine parameter constraints when the magnitude dispersion…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 B. L. Lago , M. O. Calvão , S. E. Jorás , R. R. R. Reis , I. Waga , R. Giostri
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