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The cause of the extended rotation curves of galaxies is investigated. It is shown that conventional sources and most exotic sources for the needed gravitational fields are implausible. We suggest spatial fluctuations in a scalar field,…

Astrophysics · Physics 2007-05-23 H. L. Helfer

The cosmological implications from a new estimate of the local X-ray galaxy cluster abundance are summarized. The results are then compared to independent observations. It is suggested that `low' values for the mean cosmic matter density…

Astrophysics · Physics 2007-05-23 Thomas H. Reiprich

In this work we perform some studies related to dark energy. Firstly, we propose a dynamical approach to explain the dark energy content of the universe. We assume that a massless scalar field couples to the Hubble parameter with some…

High Energy Physics - Phenomenology · Physics 2009-01-07 Fei Wang , Jin Min Yang

Standard statistical mechanical or condensed matter arguments tell us that bulk properties of a physical system do not depend too much on boundary conditions. Random tilings of large regions provide counterexamples to such intuition, as…

Statistical Mechanics · Physics 2021-03-17 Jean-Marie Stéphan

The nonsymmetric gravitational theory predicts an acceleration law that modifies the Newtonian law of attraction between particles. For weak fields a fit to the flat rotation curves of galaxies is obtained in terms of the mass…

General Relativity and Quantum Cosmology · Physics 2007-05-23 J. W. Moffat

A classical nonlocal generalization of Einstein's theory of gravitation has recently been developed via the introduction of a scalar causal "constitutive" kernel that must ultimately be determined from observational data. It turns out that…

Astrophysics of Galaxies · Physics 2014-05-14 S. Rahvar , B. Mashhoon

Gravitational lensing by clusters of galaxies has been detected on scales ranging from $\sim10^{-1}$ Mpc to $\sim10$ Mpc, namely, arcs/arclets, weak lensing and quasar-cluster associations. This allows us to derive an overall radius matter…

Astrophysics · Physics 2009-10-28 Xiang-Ping Wu , Li-Zhi Fang

The vacuum must contain virtual fluctuations of black hole microstates for each mass $M$. We observe that the expected suppression for $M\gg m_p$ is counteracted by the large number $Exp[S_{bek}]$ of such states. From string theory we learn…

High Energy Physics - Theory · Physics 2020-01-08 Samir D. Mathur

The discrepancy between dynamical mass measures of objects such as galaxies and the observed distribution of luminous matter in the universe is typically explained by invoking an unseen ``dark matter'' component. Dark matter must…

Astrophysics · Physics 2015-06-24 William H. Kinney , Martina Brisudova

It is assumed that the quantum vacuum may be studied as consisting of two contributions, with positive and negative energy respectively, which interact but slightly and may be displaced from each other. Then it is proposed that dark matter…

General Relativity and Quantum Cosmology · Physics 2008-02-08 E. S. Corchero

We explore the theoretical possibility that dark energy density is derived from the vacuum particle pairs together with the quantum fluctuation of space-time. By assuming the vacuum particle pairs fall into the horizon boundary of the…

General Relativity and Quantum Cosmology · Physics 2023-07-24 Long Huang , Xiao feng Yang , Xiang Liu

We examine the peculiar velocity distribution function of galaxies in cosmological many-body gravitational clustering. Our statistical mechanical approach derives a previous basic assumption and generalizes earlier results to galaxies with…

Astrophysics · Physics 2009-11-10 Bernard Leong , William Saslaw

The hypothesis of the scale invariance of the macroscopic empty space, which intervenes through the cosmological constant, has led to new cosmological models. They show an accelerated cosmic expansion and satisfy several major cosmological…

Astrophysics of Galaxies · Physics 2017-11-15 Andre Maeder

Galaxies are huge physical systems having dimensions of many tens of thousands of light years. Thus any change at the galactic center will be noticed at the rim only tens of thousands of years later. Those retardation effects seems to be…

General Physics · Physics 2025-05-27 Asher Yahalom

We analyze the behavior of the scalar field as dark energy of the Universe in a static world of galaxies and clusters of galaxies. We find the analytical solutions of evolution equations of the density and velocity perturbations of dark…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-22 Bohdan Novosyadlyj , Maksym Tsizh , Yurij Kulinich

In this work, one shows that a specific non-minimal coupling between the scalar curvature and matter can mimic the dark matter component of galaxy clusters. For this purpose, one assesses the Abell cluster A586, a massive nearby relaxed…

General Relativity and Quantum Cosmology · Physics 2013-01-31 Orfeu Bertolami , Pedro Frazão , Jorge Páramos

According to the Virial Theorem, all gravitational systems in equilibrium sit on a plane in the 3D parameter space defined by their mass, size and second moment of the velocity tensor. While these quantities cannot be directly observed,…

Astrophysics of Galaxies · Physics 2016-11-07 Remco van den Bosch

The application of the virial theorem provides a tool to estimate supermassive black hole (BH) masses in large samples of active galactic nuclei (AGN) with broad emission lines at all redshifts and luminosities, if the broad line region…

Astrophysics · Physics 2008-09-03 A. Marconi , D. Axon , R. Maiolino , T. Nagao , P. Pietrini , A. Robinson , G. Torricelli

The new `quantum-foam in-flow' theory of gravity has explained numerous so-called gravitational anomalies, particularly the `dark matter' effect which is now seen to be a dynamical effect of space itself, and whose strength is determined by…

General Physics · Physics 2010-07-14 Reginald T. Cahill

In the paper we discussed the observational aspects of rotation in the Universe on different scales. We show dependence between the angular momentum of the structures and their size. The presented observational situation is that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Wlodzimierz Godlowski
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