53 research outputs found
Accelerated expansion from a non-minimal gravitational coupling to matter
It is shown that a non-minimal coupling between the scalar curvature and the
matter Lagrangian density may account for the accelerated expansion of the
Universe and provide, through mimicking, for a viable unification of dark
energy and dark matter. An analytical exploration is first performed, and a
numerical study is then used to validate the obtained results. The encountered
scenario allows for a better grasp of the proposed mechanism, and sets up the
discussion for improvements that can lead to a complete agreement with the
observational data.Comment: Latex file, 10 pages, 6 figure
Solar system tests of scalar field models with an exponential potential
We consider a scenario where a scalar field has dynamics ruled by an
exponential potential, such as those arising from some quintessence type
models, and aim at obtaining phenomenological manifestations of this entity
within our Solar System. To do so, we assume a perturbative regime, derive the
perturbed Schwarzschild metric, and extract the relevant post-Newtonian
parameters.Comment: 5 page
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