English
Related papers

Related papers: A Reply to a Comment on "Dark matter: A phenomenol…

200 papers

The nature of gravity is fundamental to understand the scaffolding of the Universe and its evolution. Einstein's general theory of relativity has been scrutinized for over ninety five years and shown to describe accurately all phenomena…

General Relativity and Quantum Cosmology · Physics 2011-12-12 Orfeu Bertolami

We have fossil evidence from the thermal background radiation that our universe expanded from a considerably hotter denser state. We have a well defined and testable description of the expansion, the relativistic Friedmann-Lemaitre model.…

Astrophysics · Physics 2009-10-31 P. J. E. Peebles

Pathria(1972) has shown, for a pressureless closed Universe, that it is inside a black (or white) hole. We show now, that the Universe with a cosmic pressure obeying Einstein's field equations, can be inside a white-hole. In the closed…

General Physics · Physics 2008-11-26 Marcelo Samuel Berman

The dark matter problem is almost a century old. Since the 1930s evidence has been growing that our cosmos is dominated by a new form of non-baryonic matter, that holds galaxies and clusters together and influences cosmic structures up to…

Cosmology and Nongalactic Astrophysics · Physics 2018-01-25 Laura Baudis

In addressing the cosmological constant problem, we propose that the discrepancy between the theoretical and observed values can be ascribed to the inherent uncertainty in the spacetime metric. Mach's principle, which posits that mass…

General Relativity and Quantum Cosmology · Physics 2023-09-06 Ahmed Farag Ali , Nader Inan

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

This paper presents a brief review of the evidence for dark matter in the Universe on the scales of galaxies. In the interests of critically and objectively testing the dark matter paradigm on these scales, this evidence is weighed against…

Astrophysics · Physics 2016-11-03 M. R. Merrifield

The paper considers, within the Standard Model, physical pictures of combinations and interactions of elementary particles, which are allowed within the isotopic Foldy-Wouthuysen representation. A hypothesis is suggested and proved that the…

General Physics · Physics 2009-02-25 V. P. Neznamov

As we now know, there are indeed at least two major difficulties with General Relativity (GR). The first one is related with its incompatibility with quantum mechanics, in the absence of a widely accepted consistent theory that combines the…

General Physics · Physics 2015-06-05 Ram Gopal Vishwakarma

We apply quantum gravitational results to spatially unbounded Friedmann universes and try to answer some questions related to dark energy, dark matter, inflation and the missing antimatter.

General Relativity and Quantum Cosmology · Physics 2019-08-08 Claus Gerhardt

In a recent paper (arXiv:1106.4546), we introduced "dynamical dark matter," a new framework for dark-matter physics, and outlined its underlying theoretical principles and phenomenological possibilities. Unlike most traditional approaches…

High Energy Physics - Phenomenology · Physics 2013-05-30 Keith R. Dienes , Brooks Thomas

Based on an exact solution of the Einstein field equations, it is proposed in this note that the dark-matter hypothesis could have led to the prediction of flat galactic rotation curves long before the discovery thereof by assuming that on…

General Relativity and Quantum Cosmology · Physics 2016-06-14 Peter K. F. Kuhfittig

In a previous work [1], it was speculated that the lack of homogeneity of the large-scale structure of the universe may be due to quantum fluctuations of space in the early universe. In [1], this was argued for a Friedmann-type universe for…

General Physics · Physics 2019-10-28 Benito Hernández-Bermejo

The observational evidence for dark matter on progressively larger cosmic scales is reviewed in a rather pedagogical fashion. Although the emphasis is on dark matter in galaxies and in clusters of galaxies, its cosmological evidence as well…

Astrophysics · Physics 2007-05-23 M. Roncadelli

Modern cosmology successfully deals with the origin and the evolution of the Universe at large scales, but it is unable to completely answer the question about the nature of the fundamental objects that it is describing. As a matter of…

High Energy Physics - Phenomenology · Physics 2021-12-08 Aldo Ianni , Massimo Mannarelli , Nicola Rossi

From astronomical observations, we know that dark matter exists, makes up 23% of the mass budget of the Universe, clusters strongly to form the load-bearing frame of structure for galaxy formation, and hardly interacts with ordinary matter…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-20 Annika H. G. Peter

Based on an earlier introduced new class of generalized gravity-matter models defined in terms of two independent non-Riemannian volume forms (alternative generally covariant integration measure densities) on the space-time manifold, we…

High Energy Physics - Theory · Physics 2016-11-29 Eduardo Guendelman , Ramon Herrera , Pedro Labrana , Emil Nissimov , Svetlana Pacheva

We review the underpinnings of the standard Newton-Einstein theory of gravity, and identify where it could possibly go wrong. In particular, we discuss the logical independence from each other of the general covariance principle, the…

Astrophysics · Physics 2009-11-11 Philip D. Mannheim

Over the past three years we have determined the basic features of the Universe -- spatially flat; accelerating; comprised of 1/3 a new form of matter, 2/3 a new form of energy, with some ordinary matter and a dash of massive neutrinos; and…

Astrophysics · Physics 2009-11-07 Michael S. Turner

We propose a relativistic model of dark matter reproducing at once the concordance cosmological model $\Lambda$-Cold-Dark-Matter ($\Lambda$-CDM) at cosmological scales, and the phenomenology of the modified Newtonian dynamics (MOND) at…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Laura Bernard , Luc Blanchet
‹ Prev 1 8 9 10 Next ›