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Related papers: Torsion, an alternative to dark matter?

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From the freedom exhibited by the generalized Einstein action proposed in [1], we show that we can construct the standard effective Einstein-Cartan action coupled to the fermionic matter without the usual current-current interaction and…

General Relativity and Quantum Cosmology · Physics 2010-04-21 Meriem-Hadjer Lagraa , Mohammed Lagraa

We argue that the conjectured dark mater in the Universe may be endowed with a new kind of gravitational charge that couples to a short range gravitational interaction mediated by a massive vector field. A model is constructed that…

General Relativity and Quantum Cosmology · Physics 2010-11-30 R. W. Tucker , C. Wang

The vector-tensor (VT) theory of gravitation revisited in this article was studied in previous papers, where it was proved that VT works and deserves attention. New observational data and numerical codes have motivated further development…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-11 Roberto Dale , Diego Sáez

Decaying dark matter models generically modify the equation of state around the time of dark matter decay, and this in turn modifies the expansion rate of the Universe through the Friedmann equation. Thus, a priori, these models could solve…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-04 Andreas Nygaard , Emil Brinch Holm , Thomas Tram , Steen Hannestad

A huge amount of good quality data converges towards the picture of a spatially flat universe undergoing the today observed phase of accelerated expansion. This new observational trend is commonly addressed as Precision Cosmology. Despite…

General Relativity and Quantum Cosmology · Physics 2008-12-02 S. Capozziello

Under the existence of a massless spinor with respect to the total connection in a spacetime modeled as a Lorentzian manifold with internal boundaries, such as finite volume semi-classical Black Holes, we show that a topological mechanism…

General Relativity and Quantum Cosmology · Physics 2026-02-03 J. Lorca Espiro , Yerko Vásquez , M. Le Delliou

In the present work, torsion energy is defined. Its law of conservation is given. It is shown that this type of energy gives rise to a repulsive force which can be used to interpret supernovae type Ia observations, and consequently the…

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

In this paper, it is shown that the cosmological model that was introduced in a sequence of three earlier papers under the title, A Dust Universe Solution to the Dark Energy Problem, can be used to resolve the problem of the great mismatch…

General Physics · Physics 2010-07-21 James G. Gilson

The Covariant Canonical Gauge theory of Gravity (CCGG) is a gauge field formulation of gravity which a priori includes non-metricity and torsion. It extends the Lagrangian of Einstein's theory of general relativity by terms at least…

General Relativity and Quantum Cosmology · Physics 2023-04-13 Armin van de Venn , David Vasak , Johannes Kirsch , Jürgen Struckmeier

The analogy between electrodynamics and the translational gauge theory of gravity is employed in this paper to develop an ansatz for a nonlocal generalization of Einstein's theory of gravitation. Working in the linear approximation, we show…

General Relativity and Quantum Cosmology · Physics 2009-11-13 Friedrich W. Hehl , Bahram Mashhoon

The Hubble tension has proven to be stubbornly persistent, despite widespread efforts to relax it. As a possible resolution of this problem we propose a radical alternative to the way in which cosmological models are viewed. Specifically,…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-02 Timothy Clifton , Neil Hyatt

Evolution of gravitational perturbations, both in time and frequency domains, is considered for a spherically symmetric black hole in the non-reduced Einstein-Aether theory. It is shown that real oscillation frequency and damping rate are…

High Energy Physics - Theory · Physics 2008-11-26 R. A. Konoplya , A. Zhidenko

A rare coincidence of scales in standard particle physics is needed to explain why $\Lambda$ or the negative pressure of cosmological dark energy (DE) coincides with the positive pressure $P_0$ of random motion of dark matter (DM) in bright…

Astrophysics · Physics 2009-11-13 HongSheng Zhao

Dark energy and dark matter constitute 95% of the observable Universe. Yet the physical nature of these two phenomena remains a mystery. Einstein suggested a long-forgotten solution: gravitationally repulsive negative masses, which drive…

General Physics · Physics 2018-12-05 J. S. Farnes

In the framework of Einstein-Yang-Mills theories, we study the gauge Lorentz group and establish a particular correspondence between this case and a certain class of theories with torsion within Riemann-Cartan space-times. This relation is…

General Relativity and Quantum Cosmology · Physics 2018-03-07 Jose A. R. Cembranos , Jorge Gigante Valcarcel

We present, in closed analytic form, a general stationary, slowly rotating black hole, which is solution to a large class of alternative theories of gravity in four dimensions. In these theories, the Einstein-Hilbert action is supplemented…

General Relativity and Quantum Cosmology · Physics 2011-10-27 Paolo Pani , Caio F. B. Macedo , Luis C. B. Crispino , Vitor Cardoso

Dark energy observations may be explained within general relativity using an inhomogeneous Hubble-scale depression in the matter density and accompanying curvature, which evolves naturally out of an Einstein-de Sitter (EdS) model. We…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-10 Sean February , Julien Larena , Mathew Smith , Chris Clarkson

Recently a $f(T)$ gravity based on the modification of the teleparallel gravity was proposed to explain the accelerated expansion of the universe without the need of dark energy. We use observational data from Type Ia Supernovae, Baryon…

General Relativity and Quantum Cosmology · Physics 2016-06-06 Jing-Zhao Qi , Rong-Jia Yang , Ming-Jian Zhang , Wen-Biao Liu

The role played by torsion in gravitation is critically reviewed. After a description of the problems and controversies involving the physics of torsion, a comprehensive presentation of the teleparallel equivalent of general relativity is…

General Relativity and Quantum Cosmology · Physics 2009-11-11 H. I. Arcos , J. G. Pereira

Coupling dark energy to dark matter provides one of the simplest way to effectively modify gravity at large scales without strong constraints from local (i.e. solar system) observations. Models of coupled dark energy have been studied…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Luca Amendola , Valeria Pettorino , Claudia Quercellini , Adrian Vollmer
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