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Related papers: What Do We Really Know About Cosmic Acceleration?

200 papers

The observation that Type Ia supernovae are fainter than expected given their red shifts has led to the conclusion that the expansion of the universe is accelerating. The widely accepted hypothesis is that this acceleration is caused by a…

Cosmology and Nongalactic Astrophysics · Physics 2010-07-09 Rutger Dungan , Harrison B. Prosper

This is a pedagogical review of the recent observational data obtained from type Ia supernova surveys that support the accelerating expansion of the universe. The methods for the analysis of the data are reviewed and some of the theoretical…

Astrophysics · Physics 2007-05-23 L. Perivolaropoulos

Recent observations of Type Ia supernovae provide evidence for the acceleration of our universe, which leads to the possibility that the universe is entering an inflationary epoch. We simulate it under a ``big bounce'' model, which contains…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Beili Wang , Hongya Liu , Lixin Xu

Understanding the space of possible theoretical explanations for the observed cosmic acceleration is a central challenge of modern cosmology. This brief document sketches selected aspects of approaches to this problem, focusing on the…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-01 Mark Trodden

Although big bang cosmology effectively models even the most puzzling observational data, it offers no insight into why the cosmological expansion should occur at all. In this paper it is suggested that a finite Universe poses particular…

General Physics · Physics 2007-05-23 Alasdair Macleod

Using a general classification of dark enegy models in four classes, we discuss the complementarity of cosmological observations to tackle down the physics beyond the acceleration of our universe. We discuss the tests distinguishing the…

Astrophysics · Physics 2008-11-26 Jean-Philippe Uzan

Assuming that the Universe is filled by one single fluid, we present in the context of General Relativity a possible explanation for the acceleration of the Universe. We use ordinary thermodynamics and the fact that small matter…

General Relativity and Quantum Cosmology · Physics 2011-04-26 Orlando Luongo , Hernando Quevedo

We present a space-velocity theory of gravitation in a 4-dimensional curved space. The solutions of the field equations yield 3 possibilities for the universe expansion but only the accelerating one is possible. Although the theory has no…

Astrophysics · Physics 2007-05-23 Moshe Carmeli

Several key relations are derived for Cosmological General Relativity which are used in standard observational cosmology. These include the luminosity distance, angular size, surface brightness and matter density. These relations are used…

Astrophysics · Physics 2008-11-26 John G. Hartnett , Firmin J. Oliveira

Recent investigations seem to favor a cosmological dynamics according to which the accelerated expansion of the Universe may have already peaked and is now slowing down again \cite{sastaro}. As a consequence, the cosmic acceleration may be…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-13 Julio C. Fabris , Bernardo Fraga , Nelson Pinto-Neto , Winfried Zimdahl

It has been argued in the literature that if a universe is expanding with an accelerating rate indefinitely, it presents a challenge to string theories due to the existence of event horizons. We study the fate of a currently accelerating…

Astrophysics · Physics 2007-05-23 Xiao-Gang He

It is the common consensus that the expansion of a universe always slows down if the gravity provided by the energy sources therein is attractive and accordingly one needs to invoke dark energy as a source of anti-gravity for understanding…

Astrophysics · Physics 2008-11-26 Chia-Hsun Chuang , Je-An Gu , W-Y. P. Hwang

A major recent evelopment in observational cosmology has been an accurate measurement of the luminosity distance-redshift relation out to redshifts z=0.8 from Type Ia supernova standard candles. The results have been argued as evidence for…

Astrophysics · Physics 2016-01-13 Neil Trentham

Measurements of the distances to SNe Ia have produced strong evidence that the expansion of the Universe is accelerating, implying the existence of a nearly uniform component of dark energy with negative pressure. We show that constraints…

Astrophysics · Physics 2009-08-18 Saul Perlmutter , Michael S. Turner , Martin White

We work out an effective theory of accelerated expansion to describe general phenomena of inflation and acceleration (dark energy) in the Universe. Our aim is to determine from theoretical grounds, in a physically-motivated and model…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Raul Jimenez , P. Talavera , Licia Verde

Observations reveal a `bulk flow' in the local Universe which is faster and extends to much larger scales than is expected around a typical observer in the standard $\Lambda$CDM cosmology. This is expected to result in a scale-dependent…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-27 Jacques Colin , Roya Mohayaee , Mohamed Rameez , Subir Sarkar

The currently available cosmological data yield, as a most striking result, that the expansion rate of the universe seems to be increasing at late times, contrary to the standard (zero cosmological constant) FLRW prediction. The usual…

Astrophysics · Physics 2011-10-31 Marie-Noelle Celerier

Recent observations on the large-scale structure of the universe indicate that the cosmological constant cannot be the definitive answer to the nature of dark energy. Therefore, it is a good time to propose alternatives to understand the…

General Relativity and Quantum Cosmology · Physics 2024-09-12 I. A. Sarmiento Alvarado , Maribel Hernández Márquez , Tonatiuh Matos

Shafieloo ea al. firstly proposed the possibility that the current cosmic acceleration (CA) is slowing down. However, this is rather counterintuitive because a slowing down CA cannot be accommodated in most mainstream cosmological models.…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-14 Shuang Wang , Yazhou Hu , Miao Li , Nan Li

It is shown that the acceleration of the universe can be understood by considering a F(T) gravity models. For these F(T) gravity models, a variant of the accelerating cosmology reconstruction program is developed. Some explicit examples of…

General Relativity and Quantum Cosmology · Physics 2011-09-23 Ratbay Myrzakulov