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Related papers: Do $\Lambda_{CC}$ and $G$ run?

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This paper has been withdrawn by the author, due an error in Eq.(4.4), wherein a term of cosmological constant added into a theory of gravitation by Ref.[8], in which such the term is truly forbidden.

Astrophysics · Physics 2007-05-23 V. V. Kiselev

We have studied a cosmological model with a cosmological term of the form $\Lambda=3\alpha\fr{\dot R^2}{R^2}+\bt\fr{\ddot R}{R}+\fr{3\gamma}{R^2} \alpha, \ \bt \gamma$ are constants. The scale factor (R) is found to vary linearly with time…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Arbab I. Arbab

We are at a specific period of modern cosmology, during which the large increase of the amount of data leads to the idea that the determination of cosmological parameters has been achieved with a rather good precision. There is a large…

Astrophysics · Physics 2017-08-23 A. Blanchard

Motivated by some recent speculative attempts to model the dark energy, scalar fields with negative kinetic energy coupled to gravity without a cosmological constant are considered. It is shown that in the presence of an ordinary fluid, any…

High Energy Physics - Theory · Physics 2007-05-23 G. W. Gibbons

We advance the viewpoint that only relevant modes of the vacuum fluctuations, namely, with wavelengths conditioned by the size, homogeneity, geometry and topology of the Universe, do contribute into the cosmological constant. A formula is…

Astrophysics · Physics 2014-10-13 V. G. Gurzadyan , She-Sheng Xue

I will discuss the recent LHC and Planck results, which are completely compatible with the Standard Model of particle physics, and the standard cosmological model ($\Lambda$CDM), respectively. It turns out that the extension of the Standard…

High Energy Physics - Phenomenology · Physics 2013-12-17 Fedor Bezrukov

For relativistic energies the small angle classical cross section for scattering on a Coulomb potential agrees with the first Born approximation for quantum cross section for scalar particle only in the leading term. The disagreement in…

High Energy Physics - Theory · Physics 2009-11-13 A. I. Nikishov

The kinematic approach to cosmological tests provides a direct evidence to the present accelerating stage of the universe which does not depend on the validity of general relativity, as well as on the matter-energy content of the Universe.…

Astrophysics · Physics 2009-03-12 J. V. Cunha

Testing the cosmological variation of fundamental constants of Nature can provide valuable insights into new physics scenarios. While many such constraints have been derived for Standard Model coupling constants and masses, the $\bar\theta$…

High Energy Physics - Phenomenology · Physics 2022-10-13 Hooman Davoudiasl , Julia Gehrlein , Robert Szafron

The Cosmological Constant $\Lambda$, in different incarnations, has been with us for 100 years. Many surveys of dark energy are underway, indicating so far that the data are consistent with a dark energy equation of state of $w=-1$, i.e. a…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-04 Ofer Lahav

We compute the time variation of the fundamental constants (such as the ratio of the proton mass to the electron mass, the strong coupling constant, the fine structure constant and Newton's constant) within the context of the so-called…

High Energy Physics - Phenomenology · Physics 2017-04-03 Harald Fritzsch , Joan Sola , Rafael C. Nunes

In quantum gravity perturbation theory in Newton's constant G is known to be badly divergent, and as a result not very useful. Nevertheless some of the most interesting phenomena in physics are often associated with non-analytic behavior in…

High Energy Physics - Theory · Physics 2019-03-19 Herbert W. Hamber

It is observed that one of Einstein-Friedmann's equations has formally the aspect of a Sturm-Liouville problem, and that the cosmological constant, $\Lambda$, plays thereby the role of spectral parameter (what hints to its connection with…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-19 Artyom V. Yurov , Artyom V. Astashenok , E. Elizalde

We have shown that the phenomenological models with a cosmological constant of the type $\Lambda=\beta(\frac{\ddot R}{R})$ and $\Lambda=3\alpha H^2$, where $R$ is the scale factor of the universe and $H$ is the Hubble constant, are…

Astrophysics · Physics 2007-05-23 Arbab I. Arbab

A diverse set of observations now compellingly suggest that Universe possesses a nonzero cosmological constant. In the context of quantum-field theory a cosmological constant corresponds to the energy density of the vacuum, and the wanted…

Astrophysics · Physics 2014-10-13 Lawrence M. Krauss , Michael S. Turner

An one-parameter regularization freedom of the Hamiltonian constraint for loop quantum gravity is analyzed. The corresponding spatially flat, homogenous and isotropic model includes the two well-known models of loop quantum cosmology as…

General Relativity and Quantum Cosmology · Physics 2021-11-12 Xiangdong Zhang , Gaoping Long , Yongge Ma

We describe the linear cosmological perturbations of a perfect fluid at the level of an action, providing thus an alternative to the standard approach based only on the equations of motion. This action is suited not only to perfect fluids…

General Relativity and Quantum Cosmology · Physics 2010-04-29 Antonio De Felice , Jean-Marc Gerard , Teruaki Suyama

We examine the running vacuum model with $\Lambda (H) = 3 \nu H^2 + \Lambda_0$, where $\nu$ is the model parameter and $\Lambda_0$ is the cosmological constant. From the data of the cosmic microwave background radiation, weak lensing and…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-29 Chao-Qiang Geng , Chung-Chi Lee , Lu Yin

The cosmological constant $\Lambda$ is a measure of the energy density of the vacuum. Therefore properties of the energy of the system in the metastable vacuum state reflect properties of $\Lambda = \Lambda(t)$. We analyze properties of the…

General Relativity and Quantum Cosmology · Physics 2022-03-23 Krzysztof Urbanowski

In the framework of a model of minimal of dilatonic gravity (MDG) with cosmological potential we consider: the relations of MDG with nonlinear gravity and string theory; natural cosmological units, defined by cosmological constant; the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 P. Fiziev