English
Related papers

Related papers: Dark energy density predicted and explained

200 papers

A solution to Einstein's field equations via the Friedman equations is shown to produce a cosmological model that is in exact agreement with the measurements made by the dark energy astronomers. All the essential physical parameters are…

General Physics · Physics 2012-06-26 James G. Gilson

We examine flat models containing a dark matter component and an arbitrary dark energy component, subject only to the constraint that the dark energy satisfies the weak energy condition. We determine the constraints that these conditions…

Astrophysics · Physics 2008-11-26 A. A. Sen , Robert J. Scherrer

In a previous paper (Ref. [1]) the presence of dark energy in our universe was explained as the fingerprint of a comprehensive, much older and expanding multiverse with positive spatial curvature, whose space-time is spanned by this energy,…

General Relativity and Quantum Cosmology · Physics 2018-09-06 Rebhan Eckhard

To explain the acceleration of the cosmological expansion researchers have considered an unusual form of mass-energy generically called dark energy. Dark energy has a ratio of pressure over mass density which obeys $w=p/\rho <-1/3$. This…

High Energy Physics - Theory · Physics 2008-12-19 Max Chaves , Douglas Singleton

The presence of the dark energy allows both the acceleration and the expansion of the universe. In the case of a constant equation of state for dark energy we derived an analytical solution for the Hubble radius in terms of the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-06 Lorenzo Zaninetti

It is shown that so-called dark energy could possible be a manifestation of the gravitational vortex producing the "gravitomagnetic" (GM) force field: associated with cosmic matter rotation and inertial spacetime frame dragging. The general…

General Physics · Physics 2018-01-24 Reva Kay Williams

Dark energy is modelled by a Bose-Einstein gas of particles with an attractive interaction. It is coupled to cold dark matter, within a flat universe, for the late-expansion description, producing variations in particle-number densities.…

Cosmology and Nongalactic Astrophysics · Physics 2019-01-11 Hiram E. Lucatero--Villaseñor , German Izquierdo , Jaime Besprosvany

Observations provide increasingly strong evidence that the universe is accelerating. This revolutionary advance in cosmological observations confronts theoretical cosmology with a tremendous challenge, which it has so far failed to meet.…

Astrophysics · Physics 2008-11-26 Ruth Durrer , Roy Maartens

We study dark energy through the viewpoints of parametric and nonparametric analyses of late-time cosmological data. We consider four Hubble parameter priors reflecting the Hubble tension and make use of two phenomenological functions,…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Reginald Christian Bernardo , Daniela Grandón , Jackson Levi Said , Víctor H. Cárdenas

A huge amount of good quality astrophysical data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision…

Astrophysics · Physics 2009-06-23 S. Capozziello

Assuming that the Universe at higher redshifts (z \sim 4 and beyond) is consistent with LCDM model as constrained by the Planck measurements, we reanalyze the low redshift cosmological data to reconstruct the Hubble parameter as a function…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-18 Koushik Dutta , Ruchika , Anirban Roy , Anjan A. Sen , M. M. Sheikh-Jabbari

The effective evolution of an inhomogeneous universe model in any theory of gravitation may be described in terms of spatially averaged variables. In Einstein's theory, restricting attention to scalar variables, this evolution can be…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Thomas Buchert

We extend and apply a model-independent analysis method developed earlier by Daly & Djorgovski to new samples of supernova standard candles, radio galaxy and cluster standard rulers, and use it to constrain physical properties of the dark…

It is argued that the discovery of cosmic acceleration could have been anticipated on thermodynamic grounds, namely, the generalized second law and the approach to equilibrium at large scale factor. Therefore, the existence of dark energy…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Ninfa Radicella , Diego Pavón

We show that in imaginary time quantum metric fluctuations of empty space form a self-consistent de Sitter gravitational instanton that can be thought of as describing tunneling from "nothing" into de Sitter space of real time (no…

General Relativity and Quantum Cosmology · Physics 2015-06-04 Leonid Marochnik

As an alternative to the Standard cosmology model we have developed a new modified Freundlich's (quantum relativity) redshift (MFRS) mechanisms, which provide a precise solutions of the Dark Energy and Dark Matter problems. We apply the…

General Physics · Physics 2015-02-23 Asger G. Gasanalizade , Ramin A. Hasanalizade

The strongest evidence for dark energy comes presently from geometric techniques such as the supernova distance-redshift relation. By combining the measured expansion history with the Friedmann equation one determines the energy density and…

Astrophysics · Physics 2008-11-26 Edmund Bertschinger

Light received from a cosmological source is redshifted with an apparent loss of energy, a problem first pointed out by Edwin Hubble in 1936. A new type of energy called Hubble Energy is introduced to restore the principle of energy…

General Physics · Physics 2007-05-23 Alasdair Macleod

We present a physically motivated dark-energy (DE) model rooted in the topological structure of the Quantum ChromoDynamic (QCD) vacuum. In this framework, DE arises from the difference between the vacuum energy of an expanding FRW universe…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-03 Ludovic Van Waerbeke , Ariel Zhitnitsky

The postulate that all massless elementary fields have conformal Weyl local scaling symmetry has remarkable consequences for both cosmology and elementary particle physics. Conformal symmetry couples scalar and gravitational fields.…

General Physics · Physics 2011-09-27 R. K. Nesbet
‹ Prev 1 4 5 6 7 8 10 Next ›