Zobrazeno 1 - 10
of 100
pro vyhledávání: '"Salim, J. M."'
Publikováno v:
Class. Quantum Grav. 31 145007 (2014)
Propagation of light in nonlinear materials is here studied in the regime of the geometrical optics. It is shown that a spherically symmetric medium at rest with some specific dielectric properties can be used to produce an exact analogue model for a
Externí odkaz:
http://arxiv.org/abs/1401.7544
Autor:
Poulis, F. P., Salim, J. M.
We provide a gauge-invariant theory of gravitation in the context of Weyl Integrable Space-Times. After making a brief review of the theory's postulates, we carefully define the observers' proper-time and point out its relation with space-time descri
Externí odkaz:
http://arxiv.org/abs/1305.6830
A comprehensive review of the equations of general relativity in the quasi-Maxwellian (QM) formalism introduced by Jordan, Ehlers and Kundt is made. Our main interest concerns its applications to the analysis of the perturbation of standard cosmology
Externí odkaz:
http://arxiv.org/abs/1302.7248
Autor:
Bittencourt, E., Salim, J. M.
We have solved the Einstein equations of general relativity for a class of metrics with constant spatial curvature and found a non-vanishing Weyl tensor in the presence of an energy-momentum tensor with an anisotropic pressure component. The time evo
Externí odkaz:
http://arxiv.org/abs/1301.3079
We present a geometric scalar theory of gravity. Our proposal will be described using the "background field method" introduced by Gupta, Feynman and others as a field theory formulation of general relativity. We analyze previous criticisms against sc
Externí odkaz:
http://arxiv.org/abs/1212.0770
Autor:
Poulis, F. P., Salim, J. M.
Publikováno v:
Int. J. Mod. Phys.: Conf. Series, V. 3, 87-97 (2011)
Motivated by an axiomatic approach to characterize space-time it is investigated a reformulation of Einstein's gravity where the pseudo-riemannian geometry is substituted by a Weyl one. It is presented the main properties of the Weyl geometry and it
Externí odkaz:
http://arxiv.org/abs/1106.3031
Publikováno v:
Int.J.Geom.Meth.Mod.Phys.8:87-98,2011
We show that Quantum Mechanics can be interpreted as a modification of the Euclidean nature of 3-d space into a particular Weyl affine space which we call Q-wis. This is proved using the Bohm-de Broglie causal formulation of Quantum Mechanics. In the
Externí odkaz:
http://arxiv.org/abs/0901.3741
Publikováno v:
Int.J.Mod.Phys.A24:4009-4020,2009
We investigate if theories yielding bouncing cosmological models also generate wormhole solutions. We show that two of them present sensible traversable static wormhole solutions, while for the third possibility such solutions are absent.
Externí odkaz:
http://arxiv.org/abs/0802.4111
Publikováno v:
Int.J.Mod.Phys.A24:5639-5658,2009
Recent works have shown the important role Nonlinear Electrodynamics (NLED) can have in two crucial questions of Cosmology, concerning particular moments of its evolution for very large and for low-curvature regimes, that is for very condensed phase
Externí odkaz:
http://arxiv.org/abs/0802.1875
Publikováno v:
JCAP 0704:011,2007
We show (in a completely analytical and exact manner) that an efficient magnetic field amplification method is operative during the bounce in a time-dependent gauge coupling model. The cosmological magnetic fields so generated have particular spectra
Externí odkaz:
http://arxiv.org/abs/astro-ph/0612281