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The model of the homogenous and isotropic universe is considered in which the coordinate system of reference is not defined by the matter but is a priori specified. The scale factor of the universe changes following the linear law. The…

Astrophysics · Physics 2007-05-23 D. L. Khokhlov

The idea here is to set the cosmical constant $\lambda$ proportional to the scalar of the stress-energy tensor of the ordinary matter. We investigate the evolution of the scale factor in a cosmological model in which the cosmological…

Astrophysics · Physics 2007-05-23 V. Majernik

In the Newtonian limit of general relativity force acting on a test mass in a central gravitational field is conventionally defined by the attractive Newtonian gravity (inverse square) term plus a small repulsive cosmological force, which…

General Relativity and Quantum Cosmology · Physics 2020-05-25 Igor I. Smolyaninov

We present a new solution to the cosmological constant (CC) and coincidence problems in which the observed value of the CC, $\Lambda$, is linked to other observable properties of the universe. This is achieved by promoting the CC from a…

General Relativity and Quantum Cosmology · Physics 2015-03-17 Douglas J. Shaw , John D. Barrow

After a short history of the $\Lambda$-term it is explained why the (effective) cosmological constant is expected to obtain contributions from short-distance physics, corresponding to an energy at least as large as the Fermi scale. The…

Astrophysics · Physics 2007-05-23 Norbert Straumann

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

The discovery that the expansion of the universe is accelerating in time is a major discovery which still awaits adequate explanation. It is generally agreed that this implies a cosmic repulsion as a result of the existence of a…

General Physics · Physics 2008-11-26 R. F. O'Connell

A Universe with finite age also has a finite causal scale $\chi_\S$, so the metric can not be homogeneous for $\chi>\chi_\S$, as it is usually assumed. To account for this, we propose a new causal boundary condition, that can be fulfil by…

General Relativity and Quantum Cosmology · Physics 2019-12-03 Enrique Gaztanaga

Next year we will celebrate 100 years of the cosmological term, $\Lambda$, in Einstein's gravitational field equations, also 50 years since the cosmological constant problem was first formulated by Zeldovich, and almost about two decades of…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-14 Joan Sola

For non-zero cosmological constant Lambda, we show that the barotropic FRW cosmologies as worked out in the comoving time lead in the radiation-dominated case to scale factors of identical form as for the Chiellini dissipative scale factors…

Mathematical Physics · Physics 2015-06-17 Haret C. Rosu , Stefan C. Mancas , Pisin Chen

In this paper we provide both a diagnosis and resolution of the cosmological constant problem, one in which a large (as opposed to a small) cosmological constant $\Lambda$ can be made compatible with observation. We trace the origin of the…

Astrophysics · Physics 2009-10-31 Philip D. Mannheim

In a quest to explain the small value of the today's cosmological constant, following the approach introduced in [1], we show that the theoretical value of cosmological constant is consistent with its observational value. In more detail, we…

General Relativity and Quantum Cosmology · Physics 2015-10-08 T. Rostami , S. Jalalzadeh

The paper deals with the scale discrepancy between the observed vacuum energy in cosmology and the theoretical quantum vacuum energy (cosmological constant problem). Here, we demonstrate that Einstein's equation and an analogy to particle…

General Physics · Physics 2019-02-08 Christian Henke

We make the cosmological constant, {\Lambda}, into a field and restrict the variations of the action with respect to it by causality. This creates an additional Einstein constraint equation. It restricts the solutions of the standard…

General Relativity and Quantum Cosmology · Physics 2015-05-28 John D. Barrow , Douglas J. Shaw

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

The model of the homogenous and isotropic universe is considered in which the coordinate system of reference is not defined by the matter but is a priori specified. The scale factor of the universe changes following the linear law. The…

Astrophysics · Physics 2007-05-23 D. L. Khokhlov

We find five fundamental reasons demanding that any gravitational mass m, and the speed of light c, vary with cosmological time such that mc remains constant. This is required by the universal condition of conservation of momentum in a…

General Physics · Physics 2015-06-26 Antonio Alfonso-Faus

We have studied the closed universe model with the variable cosmological term, which is presented as a sum of two terms: Lambda=Lambda_0 -k R. First term Lambda_0 is a constant and it is describing a sum of quantum field's zero…

General Relativity and Quantum Cosmology · Physics 2007-05-23 P. I. Fomin , P. A. Nakaznoy , S. I. Vilchinskyi

We propose a time-varying cosmological constant with a fixed equation of state, which evolves mainly through its interaction with the background during most of the long history of the universe. However, such interaction does not exist in…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-18 Murli Manohar Verma

We show that scale invariance provides a solution to the fine tuning problem of the cosmological constant. We construct a generalization of the standard model of particle physics which displays exact quantum scale invariance. The matter…

High Energy Physics - Phenomenology · Physics 2011-02-02 Pankaj Jain , Subhadip Mitra , Sukanta Panda , Naveen K. Singh