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Nouvelle publication : Minkowskian Solution of General Relativity with Cosmological Constant and the Accelerating Universe

publié le 5 nov. 2014 11:13 par MegaBlackjak   [ mis à jour : 5 nov. 2014 11:15 ]

A Minkowskian solution of the equation of General Relativity (as written by Einstein in 1915) is trivial because it simply means that both members of the equation are equal to zero. However, if alternatively, one considers the complete equation with a non-zero constant Λ (Einstein 1917), a Minkowskian solution is no longer trivial because it amounts to impose a constraint on the right hand side of the equation (i.e. a non-null stress-energy tensor). If furthermore one identifies (as usual) this tensor to the one of a perfect fluid, one finds that this fluid has a positive energy density and a negative pressure that depend on the three constants of the equation (i.e. gravitational constant G, cosmological constant Λ and velocity of light c). When doing that (§1), one has to consider the “Minkowskian Vacuum” as a physical object of GR (an enigmatic non-baryonic Minkowskian fluid). Can one build a model of this object on the basis of a dynamical equilibrium between the effective gravitational attraction due to the positive energy density versus the negative pressure repulsion? We propose to study such a model, where the (enigmatic) fluid is assumed to exist only in a limited sphere whose surface acts like a “test body” sensitive to the gravitational field created by the fluid. No static equilibrium exists, but a pseudoNewtonian “dynamical equilibrium” (§2) can be reached if the pseudoEuclidean fluid is in state of expansion. Up to there, we have simply constructed a model of an “abstract Universe” (i.e. the limited sphere: There is no fluid outside this sphere!) that gives to a (purely mathematical) constant Λ a concrete physical meaning. We discover finally that our expanding fluid has not only dynamical (gravitational) properties (§3) but also optical properties that are connected with Doppler Redshift (§4). Remembering that recent observations in Cosmology indicate that the “real Universe” seems to be “Flat” and in “Accelerated Expansion”; remembering also (after all) that the archetypal Flat Universe is simply a Minkowskian Universe, we logically wonder if the unexpected Minkowskian global solution, could not be also a significant cosmological model (conclusion).

Nouveaux articles disponibles

publié le 7 mars 2014 10:13 par MegaBlackjak   [ mis à jour : 7 mars 2014 10:15 ]

Nouvelle note disponible

publié le 27 août 2010 06:57 par MegaBlackjak

An unexpected Minkowskian Solution of Einstein’s Equation of General Relativity with Cosmological Constant.

Un nouveau document est disponible

publié le 6 mai 2010 06:40 par ypiersea@ulb.ac.be   [ mis à jour : 6 mai 2010 06:44 ]

Manifeste pour une nouvelle révolution relativiste: est-il raisonnable de séparer une hyperbole de ses asymptotes?

Nouvelle rubrique ''Livre"

publié le 28 avr. 2010 14:22 par MegaBlackjak

La rubrique "Livre" a été ajoutée.
Vous pourrez y télécharger la préface du livre de Yves Pierseaux (La "structure fine" de la Relativité Restreinte) publié aux éditions l'Harmattan.

Nouveau look et nouvelle publication

publié le 21 avr. 2010 12:10 par MegaBlackjak

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