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Related papers: Is the Universe really expanding?

200 papers

The interpretation of the expanding universe as an expansion of space has recently been challenged. From the geodesic equation in Friedmann universe models and the empty Milne model, we argue that a Newtonian or special relativistic…

Astrophysics · Physics 2009-11-11 Oyvind Gron , Oystein Elgaroy

Supernovae are bright luminous stellar objects observable up to redshifts close to z~1. They are used to probe the geometry of the Universe and its expansion rate by applying different methods. In this article, I review various approaches…

Astrophysics · Physics 2011-04-15 P. Ruiz-Lapuente

The Standard Cosmological Model has experienced tremendous success at reproducing observational data by assuming a universe dominated by a cosmological constant and dark matter in a flat geometry. However, several studies, based on local…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-29 Jailson S. Alcaniz , Jacinto P. Neto , Farinaldo S. Queiroz , Deivid R. da Silva , Raimindo Silva

A new speculative model for the expansion of our universe has been under development by the author for the last two decades, which correctly predicts astronomical measurements with no dark matter or dark energy. This new closed model (no…

General Physics · Physics 2010-02-16 Charles B. Leffert

The traditional "explanation" for the observed acceleration of the universe is the existence of a positive cosmological constant. However, this can hardly be a truly convincing explanation, as an expanding universe is not expected to have a…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Joan Sola

Current evidence suggests that the cosmological constant is not zero, or that we live in an open universe. We examine the implications for the future under these assumptions, and find that they are striking. If the Universe is cosmological…

Astrophysics · Physics 2009-10-31 Lawrence M. Krauss , Glenn D. Starkman

In this paper we consider generalization of classical and quantum mechanics that directly follows from the causality principle and topology of a system state space. In generalized mechanics, the Hamiltonian/Schrodinger equations remain the…

General Physics · Physics 2022-04-04 Uziel Sandler

Currently available Type Ia distant supernovae observed data seem to support evidence that the cosmic expansion of the universe is accelerating. This unexpected result is beyond any standard model of modern cosmology. The new concept…

Astrophysics · Physics 2008-03-21 D. C. Choudhury

Using a single dilaton field, a unified model of the Universe is proposed, which evolves from the radiation-like dominance in the Big Bang, to the dark-matter-like dominance in the early Universe, to the coexistence of both dark-matter-like…

Astrophysics · Physics 2007-05-23 C. J. Gao , S. N. Zhang

From the equivalence principle, one gets the strength of the gravitational effect of a mass $M$ on the metric at position r from it. It is proportional to the dimensionless parameter $\beta^2 = 2GM/rc^2$, which normally is $<< 1$. Here $G$…

General Physics · Physics 2013-11-22 Antonio Alfonso-Faus , Màrius Josep Fullana i Alfonso

Popular accounts of exciting discoveries often draw students to physics and astronomy, but at the introductory level it is challenging to connect with these in a meaningful way. The use of real astronomical data in the classroom can help…

Physics Education · Physics 2021-03-16 Jeffrey M. Hyde

A new varying-$c$ cosmological model constructed using two additional assumptions, which was introduced in our previous work, is briefly reviewed and the dynamic equation of the model is derived distinctly from a semi-Newtonian approach.…

General Relativity and Quantum Cosmology · Physics 2010-09-28 Hossein Shojaie , Mehrdad Farhoudi

The standard interpretation of the observed redshifted spectra and luminosities towards distant astrophysical objects is that the universe is expanding, an inference which is found to be consistent with other cosmological probes as well.…

General Physics · Physics 2013-08-06 Meir Shimon

The most exciting future observation in cosmology will feature a monitoring of the cosmic expansion in real time, unlike anything that has ever been attempted before. This campaign will uncover crucial physical properties of the various…

General Relativity and Quantum Cosmology · Physics 2022-12-14 Fulvio Melia

We demonstrate that as we extrapolate the current $\Lambda$CDM universe forward in time, all evidence of the Hubble expansion will disappear, so that observers in our "island universe" will be fundamentally incapable of determining the true…

Astrophysics · Physics 2009-06-23 Lawrence M. Krauss , Robert J. Scherrer

A new model of accelerating expansion of the universe is presented. A de Sitter solution in vacuum and a exact solution with the dust mater source are obtained. A new explanation of the acceleration of the cosmic expansion is given. In is…

General Physics · Physics 2013-01-16 G. Y. Chee

In the late 1990's, observations of 93 Type Ia supernovae were analysed in the framework of the FLRW cosmology assuming these to be `standard(isable) candles'. It was thus inferred that the Hubble expansion rate is accelerating as if driven…

Cosmology and Nongalactic Astrophysics · Physics 2021-09-13 Roya Mohayaee , Mohamed Rameez , Subir Sarkar

Almost all cosmologists accept nowadays that the redshift of the galaxies is due to the expansion of the Universe (cosmological redshift), plus some Doppler effect of peculiar motions, but can we be sure of this fact by means of some other…

Cosmology and Nongalactic Astrophysics · Physics 2015-01-08 Martin Lopez-Corredoira

Recent observations of high-redshift supernovae seem to suggest that the global geometry of the Universe may be affected by a `cosmological constant', which acts to accelerate the expansion rate with time. But these data by themselves still…

Astrophysics · Physics 2009-10-31 Idit Zehavi , Avishai Dekel

It is shown that the Hubble constant can be derived from the standard luminosity function of galaxies as well as from a new luminosity function as deduced from the mass-luminosity relationship for galaxies. An analytical expression for the…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-20 Lorenzo Zaninetti