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A general-relativistic theory of cosmology, the dynamical variables of which are those of Hubble's, namely distances and redshifts, is presented. The theory describes the universe as having a three-phase evolution with a decelerating…

Astrophysics · Physics 2007-05-23 S. Behar , M. Carmeli

Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motion and on the strength of the…

General Relativity and Quantum Cosmology · Physics 2017-07-25 Hauret Clementine , Magain Pierre , Biernaux Judith

In the standard cosmological theory one uses the Einstein concepts of space and time as were originally introduced for the special theory of relativity and the general relativity theory. According to this approach all physical quantities…

Astrophysics · Physics 2007-05-23 Moshe Carmeli

We present here the transformations required to recast the Robertson-Walker metric and Friedmann-Robertson-Walker equations in terms of observer-dependent coordinates for several commonly assumed cosmologies. The overriding motivation is…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Fulvio Melia , Majd Abdelqader

A holistic view of the cosmological appearance and development of space is obtained by studying space as a spherically closed surface of a 4-sphere in a zero energy balance between motion and gravitation. Such an approach re-establishes…

Astrophysics · Physics 2009-11-13 Tuomo Suntola

Time is a parameter playing a central role in our most fundamental modeling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motions and on the strength of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-11 Pierre Magain , Clémentine Hauret

Time is a parameter playing a central role in our most fundamental modelling of natural laws. Relativity theory shows that the comparison of times measured by different clocks depends on their relative motions and on the strength of the…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-05 Pierre Magain , Clémentine Hauret

A Five dimensional Kaluza-Klein space-time is considered in the presence of a perfect fluid source with variable G and $\Lambda$. An expanding universe is found by using a relation between the metric potential and an equation of state. The…

General Relativity and Quantum Cosmology · Physics 2011-03-07 R. K. Tiwari , Farook Rahaman , Saibal Ray

In an attempt to generalize general relativity, we propose a new Hermitian theory of gravity. Space-time is generalized to space-time-momentum-energy and both the principles of general covariance and equivalence are extended. The theory is…

General Relativity and Quantum Cosmology · Physics 2008-05-30 Christiaan Mantz , Tomislav Prokopec

In this paper the four-dimensional space-velocity Cosmological General Relativity of Carmeli is developed by a general solution to the Einstein field equations. The metric is given in the Tolman form and the vacuum mass density is included…

General Relativity and Quantum Cosmology · Physics 2014-07-31 Firmin J. Oliveira

The notion of time in cosmology is revealed through an examination of transition matrix elements of radiative processes occurring in the cosmos. To begin with, the very concept of time is delineated in classical physics in terms of…

General Relativity and Quantum Cosmology · Physics 2009-10-30 R. Brout , R. Parentani

We consider spacetime to be a 4-dimensional differentiable manifold that can be split locally into time and space. No metric, no linear connection are assumed. Matter is described by classical fields/fluids. We distinguish electrically…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Friedrich W. Hehl , Yuri N. Obukhov

A new version of the modified theory of gravity is formulated in which two physical metrics are constructed out of two vierbeins connected with each other by the duality condition including the flat metric of the prior geometry. The duality…

General Relativity and Quantum Cosmology · Physics 2025-05-20 V. I. Tselyaev

This paper is a generalization of earlier papers [Nucl. Phys. B 884, 344 (2014) (arXiv:1312.2759) and JHEP 6, 63 (2015) (arXiv:1401.2488)]. We generalize the idea of quantum clock time to quantum spacetime reference frame via physical…

General Relativity and Quantum Cosmology · Physics 2018-03-20 M. J. Luo

Almost a century ago, Hubble discovered the cosmological redshift of extragalactic objects. The Friedmann-Lema\^itre-Robertson-Walker (FLRW) metric was presented as a solution of Einstein's field equations for a homogeneous and isotropic…

Cosmology and Nongalactic Astrophysics · Physics 2025-02-25 Juan De Vicente

We use astrophysical data to shed light on fundamental physics by constraining parametrized theoretical cosmological and gravitational models. Gravitational parameters are those constants that parametrize possible departures from Einstein's…

Astrophysics · Physics 2008-08-18 Yi Mao

The Friedmann equation is derived for a Newtonian universe. Changing mass density to energy density gives exactly the Friedmann equation of general relativity. Accounting for work done by pressure then yields the two Einstein equations that…

Astrophysics · Physics 2015-06-24 Thomas F. Jordan

Quantum cosmology describes universe as a relativistic object with an evolution defined by an equation for the energy density corresponding to the least action principle: (Taganov, 2008). In quantum cosmology this equation plays the same…

General Physics · Physics 2008-11-26 Igor N. Taganov

Space-Time in general relativity is a dynamical entity because it is subject to the Einstein field equations. The space-time metric provides different geometrical structures: conformal, volume, projective and linear connection. A deep…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ignacio Sanchez-Rodriguez

In five dimensional cosmological models, the convention is to include the fifth dimension in a way similar to the other space dimensions. In this work we attempt to introduce the fifth dimension in a way that a time dimension would be…

General Relativity and Quantum Cosmology · Physics 2013-07-09 Gizem Sengor , Metin Arik
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