English
Related papers

Related papers: {\it Gauging} the cosmic acceleration with recent …

200 papers

Absolute distances from strong lensing can anchor Type Ia Supernovae (SNe Ia) at cosmological distances giving a model-independent inference of the Hubble constant ($H_0$). Future observations could provide strong lensing time-delay…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-29 Xiaolei Li , Ryan E. Keeley , Arman Shafieloo , Kai Liao

In this paper a new theory of Dark Matter is proposed. Experimental analysis of several Galaxies show how the non-gravitational contribution to galactic Velocity Rotation Curves can be interpreted as that due to the Cosmological Constant…

Astrophysics · Physics 2007-05-23 G. V. Kraniotis , S. B. Whitehouse

The accelerating expansion of the Universe is one of the most surprising and potentially profound discoveries of modern cosmology. Measuring the acceleration well enough to meaningfully constrain interesting physical models requires…

Astrophysics · Physics 2009-11-13 G. Aldering

We perform a number of inter-related cosmographic fits to the legacy05 and gold06 supernova datasets. We pay particular attention to the influence of both statistical and systematic uncertainties, and also to the extent to which the choice…

General Relativity and Quantum Cosmology · Physics 2007-07-31 Celine Cattoen , Matt Visser

Late-time power law expansion has been proposed as an alternative to the standard cosmological model and shown to be consistent with some low-redshift data. We test power law expansion against the standard flat $\Lambda$CDM cosmology using…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-10 Daniel L. Shafer

Assuming a spatially flat universe, we study the cosmological viability of an infrared corrected teleparallel gravity model, which accounts for late acceleration by weakening gravity at later times on cosmological distances. The theory does…

Cosmology and Nongalactic Astrophysics · Physics 2023-01-11 Mahmoud Hashim , Waleed El Hanafy , Alexey Golovnev , Amr A. El-Zant

We have shown (Colin et al., 2019) that the acceleration of the Hubble expansion rate inferred from Type Ia supernovae (SNe Ia) is, at $3.9\sigma$ significance, a dipole approximately aligned with the CMB dipole, while its monopole…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-24 Jacques Colin , Roya Mohayaee , Mohamed Rameez , Subir Sarkar

Review article on the cosmological implications of Type Ia Supernovae for Europhysics News.

Astrophysics · Physics 2009-07-06 Bruno Leibundgut , Jesper Sollerman

A gravitational field model based on two symmetric tensors, $g_{\mu \nu}$ and $\tilde{g}_{\mu \nu}$, is studied, using a Markov Chain Monte Carlo (MCMC) analysis with the most updated catalog of SN-Ia. In this model, new matter fields are…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-12 Jorge Alfaro , Marco San Martin , Joaquin Sureda

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

The expansion of the Universe in $f(R,T)$ gravity is studied. We consider functions of the form $f(R,T)=R+\lambda T^\epsilon$ where $\epsilon<1$. We find that for all models with $\epsilon<0$, the Universe transitions to exponential growth…

General Relativity and Quantum Cosmology · Physics 2026-03-26 Vincent R. Siggia , Eric D. Carlson , P. Lee Pryor

Probes of cosmic expansion constitute the main basis for arguments to support or refute a possible apparent acceleration due to different expansion rates in the universe as described by inhomogeneous cosmological models. We present in this…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 Mustapha Ishak , Austin Peel , M. A. Troxel

We re-examine the contentious question of constraints on anisotropic expansion from Type Ia supernovae (SNIa) in the light of a novel determination of peculiar velocities, which are crucial to test isotropy with supernovae out to distances…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-08 W. Rahman , R. Trotta , S. S. Boruah , M. J. Hudson , D. A. van Dyk

The formal division of the distance indicators into primary and secondary leads to difficulties in description of methods which can actually be used in two ways: with, and without the support of the other methods for scaling. Thus instead…

A range of cosmological observations demonstrate an accelerated expansion of the Universe, and the most likely explanation of this phenomenon is a cosmological constant. Given the importance of understanding the underlying physics, it is…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-07 Karoline Loeve , Kristine Simone Nielsen , Steen H. Hansen

We use two large collections of observational data of supernovae type Ia (SNe Ia) to investigate the polytropic Universe including the situation with a varying cosmological constant; details of our new derivations are presented. We examine…

General Relativity and Quantum Cosmology · Physics 2018-01-17 Ahmet M. Oztas , Emre Dil , Elif Dil , Michael L. Smith

Assuming only a homogeneous and isotropic universe and using both the 'Gold' Supernova Type Ia sample of Riess et al. and the results from the Supernova Legacy Survey, we calculate the Bayesian evidence of a range of different…

Astrophysics · Physics 2011-01-20 Oystein Elgaroy , Tuomas Multamaki

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

Cosmic acceleration is investigated through a kink-like expression for the deceleration parameter (q). The new parametrization depends on the initial (q_i) and final (q_f) values of q, on the redshift of the transition from deceleration to…

Astrophysics · Physics 2009-06-23 Emille E. O. Ishida , Ribamar R. R. Reis , Alan V. Toribio , Ioav Waga

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