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Related papers: Lambda Perturbations of Keplerian Orbits

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We extend the results of a previous paper where a model of interacting dark energy, with a cosmological term decaying linearly with the Hubble parameter, is tested against the observed mass power spectrum. In spite of the agreement with…

Astrophysics · Physics 2008-12-30 H. A. Borges , S. Carneiro , J. C. Fabris

Starting from a recently proposed framework for the evaluation of the cosmological averages, we evaluate the higher-order moments for the distribution of a given observable. Then, we explicitly discuss the case of the Hubble-Lema\^itre…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-28 Tiziano Schiavone , Enea Di Dio , Giuseppe Fanizza

We simulate the astrometric observations of stars moving close to the black hole in the Galactic Center. We show, that for orbits =<1000 AU and position measurements with the accuracy of the Keck Interferometer, the periastron motion of…

Astrophysics · Physics 2007-05-23 M. Jaroszynski

The common nature of dark matter and dark energy is argued in [1] based on the approach that the cosmological constant \Lambda enters the weak-field General Relativity following from Newton theorem on the "sphere-point mass" equivalency…

General Physics · Physics 2019-02-27 V. G. Gurzadyan , A. Stepanian

Radio timing observations of a millisecond pulsar in orbit around the Galactic centre black hole (BH) or a BH at the centre of globular clusters could answer foundational questions in astrophysics and fundamental physics. Pulsar radio…

High Energy Astrophysical Phenomena · Physics 2021-01-04 Tom Kimpson , Kinwah Wu , Silvia Zane

The evolution of galaxy clusters can be affected by the repulsion described by the cosmological constant. This conclusion is reached within the modified weak-field General Relativity approach where the cosmological constant \Lambda enables…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-14 V. G. Gurzadyan , A. A. Kocharyan , A. Stepanian

We consider a cosmology with decaying metastable dark energy and assume that a decay process of this metastable dark energy is a quantum decay process. Such an assumption implies among others that the evolution of the Universe is…

General Relativity and Quantum Cosmology · Physics 2019-09-27 Aleksander Stachowski , Marek Szydlowski , Krzysztof Urbanowski

The radial velocity curves of many spectroscopic binaries (SBs) are perturbed by gas streams or proximity effects. For SBs with circular orbits, these perturbations can give rise to spurious orbital eccentricities of high statistical…

Astrophysics · Physics 2009-11-11 L. B. Lucy

We consider the Kepler two-body problem in presence of the cosmological constant $\Lambda$. Contrary to the classical case, where finite solutions exist for any angular momentum of the system $L$, in presence of $\Lambda$ finite solutions…

General Relativity and Quantum Cosmology · Physics 2019-10-23 G. S. Bisnovatyi-Kogan , M. Merafina

The possibility that the vacuum energy density $\rho_\Lambda$ is, indeed, varying in time, has been investigated lately from the running vacuum models perspective. Motivated by such models, in the present work, we relate the decaying vacuum…

General Relativity and Quantum Cosmology · Physics 2019-12-24 J. R. L. Santos , P. H. R. S. Moraes

Phenomena currently attributed to Dark Energy (DE) and Dark Matter (DM) are merely a result of the interplay between gravitational energy density, generated by the contraction of space by matter, and the energy density of the Cosmological…

Astrophysics · Physics 2008-12-25 Shlomo Barak , Elia M Leibowitz

The Einstein equation in a semi-classical approximation is applied to a spherical region of the universe, with the stress-energy tensor consisting of the mass density and pressure of the LambdaCDM cosmological model plus an additional…

General Relativity and Quantum Cosmology · Physics 2024-12-11 Emilio Santos

We show that phantom dark energy, if it is described by a K-essence theory, has three fundamental problems: first, its hamiltonian is unbounded from below. Second, classical stability precludes the equation of state from crossing the…

Astrophysics · Physics 2009-11-13 L. Raul Abramo , Nelson Pinto-Neto

Einstein's field equations with a background source term that induces perturbations and the applications of this new formalism to a compact dense matter relativistic star are presented. We introduce a new response kernel in the field…

High Energy Astrophysical Phenomena · Physics 2024-04-29 Seema Satin

Previously defined covariant and gauge-invariant perturbation variables, representing, e.g., the fractional spatial energy density gradient on hypersurfaces of constant expansion, are used to simplify the linear perturbation analysis of a…

Astrophysics · Physics 2009-10-30 Winfried Zimdahl

We study the effect of cosmological expansion on orbits--galactic, planetary, or atomic--subject to an inverse-square force law. We obtain the laws of motion for gravitational or electrical interactions from general relativity--in…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Gregory S. Adkins , Jordan McDonnell , Richard N. Fell

A mathematical model is given for the occurrence of preferred orbits and orbital velocities in a Keplerian system. The result can be extended into energies and other properties of physical systems. The values given by the model fit closely…

General Physics · Physics 2008-08-03 Ari Lehto

This paper deals with the cancellation mechanism, which identifies the energy density of space-time expansion in an empty universe with the zero-point energy density and avoids the scale discrepancy with the observed energy density…

General Physics · Physics 2018-06-12 Christian Henke

We examine the orbital dynamics of the planar pseudo-Newtonian Copenhagen problem, in the case of a binary system of Schwarzschild-like primaries, such as super-massive black holes. In particular, we investigate how the Jacobi constant…

General Relativity and Quantum Cosmology · Physics 2019-07-23 Euaggelos E. Zotos , Fredy L. Dubeibe , Jan Nagler , Emilio Tejeda

In this paper a new theory of Dark Matter is proposed. Experimental analysis of several Galaxies show how the non-gravitational contribution to galactic Velocity Rotation Curves can be interpreted as that due to the Cosmological Constant…

Astrophysics · Physics 2007-05-23 G. V. Kraniotis , S. B. Whitehouse