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Related papers: Cosmic coincidence or graviton mass?

200 papers

In this paper, it is shown that the cosmological model that was introduced in a sequence of three earlier papers under the title, A Dust Universe Solution to the Dark Energy Problem can be used to analyse and solve the Cosmological…

General Physics · Physics 2008-07-13 James G. Gilson

It is a mystery why the density of matter and the density of vacuum energy are nearly equal today when they scale so differently during the expansion of the Universe. We suggest a paradigm that might allow for a non-anthropic solution to…

Astrophysics · Physics 2009-11-07 Kim Griest

A framework is suggested in which the energy integrals of the Friedmann cosmology are identified as genuine time-independent physical characteristics for both vacuum and non-vacuum forms of cosmic energy. The integrals are found to be…

Astrophysics · Physics 2009-11-06 Arthur D. Chernin

The coincidence problem among the pure numbers of order near 10^{40} is resolved with the Raychaudhuri and Friedmann-Robertson-Lemaitre-Walker equations and a trivial relationship involving the fine structure constant. The fact that the…

General Physics · Physics 2009-11-11 Scott Funkhouser

This is an essay sketching the line of thinking which has led the present author to propose the constituent or atomic model of gravitation more than a decade ago. It turns out that viewing the problem of gravitation as a quantum many body…

Astrophysics · Physics 2009-10-19 Pawel O. Mazur

Based on Padmanabhan's theory, the spatial expansion of the Universe can be explained by the emergence of space as cosmic time progresses. To further explore this idea, we have developed fractional-fractal Friedmann and Raychaudhuri…

General Relativity and Quantum Cosmology · Physics 2023-09-29 P. F. da Silva Junior , E. W. de Oliveira Costa , S. Jalalzadeh

Detailed observations of the temperature fluctuations in the microwave background radiation indicate that we live in an open universe. From the size of these fluctuations it is concluded that the geometry of the universe is quite close to…

Astrophysics · Physics 2009-11-07 Selcuk Bayin

One of the greatest challenges of science is to understand the current accelerated expansion of the Universe. In this work, we show that by considering the quantum nature of the gravitational field, its wavelength can be associated with an…

General Physics · Physics 2022-11-08 Tonatiuh Matos , Laura L-Parrilla

In this work we present a derivation of modified Raychaudhuri and Friedmann equations from a phenomenological model of quantum gravity based on the thermodynamics of spacetime. Starting from general gravitational equations of motion which…

General Relativity and Quantum Cosmology · Physics 2023-09-13 Ana Alonso-Serrano , Marek Liška , Antonio Vicente-Becerril

We review the cosmological evidence for a low matter density universe and a cosmological constant or dynamical vacuum energy and address the cosmolog$ coincidence problem: why is the matter density about one-half the vacuum energy {\em…

Astrophysics · Physics 2015-06-24 Sidney A. Bludman

It has been shown beyond reasonable doubt that the majority (about 95%) of the total energy budget of the universe is given by the dark components, namely Dark Matter and Dark Energy. What constitutes these components remains to be…

General Relativity and Quantum Cosmology · Physics 2021-02-08 Saurya Das , Mohit Kumar Sharma , Sourav Sur

The fact that the energy densities of dark energy and matter are similar currently, known as the coincidence problem, is one of the main unsolved problems of cosmology. We present here a model in which a spatial curvature of the universe…

Astrophysics · Physics 2009-11-13 Urbano Franca

Here, non-minimally coupled tachyon to gravity is considered as a source of "dark energy". It is demonstrated that with expansion of the universe, tachyon dark energy decays to "dark matter" providing a solution to "cosmic coincidence…

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. K. Srivastaca

The integrals of the Friedmann cosmology equations are identified as constant physical characteristics for both vacuum and non-vacuum cosmic energies. The integrals are found to be numerically coincident. A model shows that the coincidence…

Astrophysics · Physics 2016-08-30 Arthur D. Chernin

It has been suggested that the Dark Energy Coincidence Problem could be interpreted as a possible link between the cosmological constant and a massive graviton. We show that by using that link and models for the graviton mass a dark energy…

General Relativity and Quantum Cosmology · Physics 2009-11-11 M. Tajmar

Recent observations suggest that a large fraction of the energy density of the universe has negative pressure. One explanation is vacuum energy density; another is quintessence in the form of a scalar field slowly evolving down a potential.…

Astrophysics · Physics 2009-09-15 Ivaylo Zlatev , Limin Wang , Paul J. Steinhardt

The novel idea is that the undergoing accelerated expansion of the universe happens due to infrared quantum gravity modifications at intermediate astrophysical scales of galaxies or galaxy clusters, within the framework of Asymptotically…

General Relativity and Quantum Cosmology · Physics 2021-02-16 Fotios K. Anagnostopoulos , Georgios Kofinas , Vasilios Zarikas

In a recent paper (Vigoureux et al. Int. J. Theor. Phys. 47:928, 2007) it has been suggested that the velocity of light and the expansion of the universe are two aspects of one single concept connecting space and time in the expanding…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-22 David Viennot , Jean-Marie Vigoureux

A novel idea is proposed for a natural solution of the dark energy and its cosmic coincidence problem. The existence of local antigravity sources, associated with astrophysical matter configurations distributed throughout the universe, can…

General Relativity and Quantum Cosmology · Physics 2018-07-04 Georgios Kofinas , Vasilios Zarikas

Taking a quantum corrected form of Raychaudhuri equation in a geometric background described by a Lorentz-violating massive theory of gravity, we go through investigating a time-like congruence of massive gravitons affected by a Bohmian…

General Physics · Physics 2016-07-08 Mohsen Fathi , Morteza Mohseni
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