Dark matter as a dynamic effect due to a non-minimal gravitational coupling with matter (I): Analytical results
Orfeu Bertolami,Jorge Páramos +1 more
- Vol. 222, Iss: 1, pp 012010
TLDR
In this article, the phenomenology of models possessing a non-minimal coupling between matter and geometry is discussed, with a particular focus on the possibility of describing the flattening of the galactic rotation curves as a dynamically generated effect derived from this modification to General Relativity.Abstract:
In this work the phenomenology of models possessing a non-minimal coupling between matter and geometry is discussed, with a particular focus on the possibility of describing the flattening of the galactic rotation curves as a dynamically generated effect derived from this modification to General Relativity. Two possibilities are discussed: firstly, that the observed discrepancy between the measured rotation velocity and the classical prediction is due to a deviation from geodesic motion, due to a non-(covariant) conservation of the energy-momentum tensor; secondly, that even if the principle of energy conservation holds, the dynamical effects arising due to the non-trivial terms in the Einstein equations of motion can give rise to an extra density contribution that may be interpreted as dark matter. In this work, The mechanism of the latter alternative is detailed; a numerical session ascertaining the order of magnitude of the relevant parameters is undertaken in another contribution to this volume, with possible cosmological implications discussed.read more
Citations
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Nonminimal curvature-matter coupled wormholes with matter satisfying the null energy condition
TL;DR: In this paper, the exact solutions of wormhole geometries supported by a non-minimal curvature-matter coupling were found, where the nonminimal coupling minimizes the violation of the null energy condition of normal matter at the throat.
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The simplest non-minimal matter–geometry coupling in the f ( R , T ) cosmology
TL;DR: In this article, a cosmological model from the simplest non-minimal matter-geometry coupling within the f(R, T) gravity formalism, by means of an effective energy-momentum tensor, given by the sum of the usual matter energy momentum tensor with a dark energy contribution, with the latter coming from the matter geometry coupling terms.
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Palatini formulation of modified gravity with a non-minimal curvature-matter coupling
TL;DR: In this paper, the authors derived the field equations and the equations of motion for scalar fields and massive test particles in modified theories of gravity with an arbitrary coupling between geometry and matter by using the Palatini formalism.
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Palatini formulation of modified gravity with a nonminimal curvature-matter coupling
TL;DR: In this paper, the authors derived the field equations and the equations of motion for massive test particles in modified theories of gravity with an arbitrary coupling between geometry and matter by using the Palatini formalism.
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Chameleon Brans-Dicke cosmology
TL;DR: In this paper, a generalized Brans-Dicke model with a potential function and the scalar field has a coupling function was considered and it was shown that the coupling function is closely related to magnitude and direction of the energy transfer between matter and the scale field.
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