Search results for "[PACS] Cosmology"
showing 4 items of 4 documents
Metaphysics of cosmological models
2023
This article aims to address the metaphysical dimension of cosmological models, be they mythological, philosophical, religious or modern scientific models, using multidisciplinary and transdisciplinary methodology. Such an approach is a novelty, both in the theological field and in the philosophical field and secular sciences, which studies the origin of humans and the universe. Contribution: The originality of this article consists in introducing the concept of transcendental cosmology, which, along with spiritual cosmology, can be a serious theological and philosophical reply to the Bing Bang theory.
Brane-world and loop cosmology from a gravity–matter coupling perspective
2015
We show that the effective brane-world and the loop quantum cosmology background expansion histories can be reproduced from a modified gravity perspective in terms of an $f(R)$ gravity action plus a $g(R)$ term non-minimally coupled with the matter Lagrangian. The reconstruction algorithm that we provide depends on a free function of the matter density that must be specified in each case and allows to obtain analytical solutions always. In the simplest cases, the function $f(R)$ is quadratic in the Ricci scalar, $R$, whereas $g(R)$ is linear. Our approach is compared with recent results in the literature. We show that working in the Palatini formalism there is no need to impose any constrai…
Cosmological Constant and Local Gravity
2010
We discuss the linearization of Einstein equations in the presence of a cosmological constant, by expanding the solution for the metric around a flat Minkowski space-time. We demonstrate that one can find consistent solutions to the linearized set of equations for the metric perturbations, in the Lorentz gauge, which are not spherically symmetric, but they rather exhibit a cylindrical symmetry. We find that the components of the gravitational field satisfying the appropriate Poisson equations have the property of ensuring that a scalar potential can be constructed, in which both contributions, from ordinary matter and Lambda > 0, are attractive. In addition, there is a novel tensor potentia…