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International Journal of Modern Physics D, 1995
The kinematical properties of the de Sitter space-time are reviewed and investigated. The properties of the static sections are clarified. A deduction of the analytic extension, analogous to that of Kruskal and Szekeres for the Schwarzschild space-time, of the static section to the region outside the horizon is given.
E. ERIKSEN, Ø. GRØN
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The kinematical properties of the de Sitter space-time are reviewed and investigated. The properties of the static sections are clarified. A deduction of the analytic extension, analogous to that of Kruskal and Szekeres for the Schwarzschild space-time, of the static section to the region outside the horizon is given.
E. ERIKSEN, Ø. GRØN
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Stochastic behaviour of de Sitter universes
Physics Letters A, 1985Abstract A stochastization procedure applied to mini-universe (friedmons) leads to a nonzero average minimum radius and thus to the exclusion of classical singularities.
M. Novello, L.A.R. Oliveira
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Solitonic instabilities in de sitter universes
Physics Letters A, 1988Abstract We present three new exact solutions of the four-dimensional Einstein field equations, that can be interpreted as solitonic perturbations of a vacuum de Sitter spacetime, obtained by means of the inverse scattering technique. The solutions are unstable against this type of perturbations, in spite of the fact that they arbitrary small for ...
Mario C. Díaz +2 more
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The de Sitter universe and mechanics
General Relativity and Gravitation, 1977If we study the de Sitter universe with the methods of projective geometry, we obtain a new mechanics valid on a cosmic scale and for hyperdense matter. In this projective mechanics the mass varies with the space-time distance, and the linear and angular momentum are reunited in a single projective tensor.
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An analogue of de-Sitter universe
Acta Physica Hungarica, 1990It is shown that the perfect fluid distribution without cosmological constant is quite analogous to homogeneous de-Sitter type universe with equation of statep+p=0. Some physical and geometrical properties of the model are also studied.
R. R. Pattanaik, G. Mohanty
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A second anti-de Sitter universe
Classical and Quantum Gravity, 2008The anti-de Sitter universe is a solution of Einstein's equations with a negative cosmological constant and zero energy tensor. I show that there is another solution with these characteristics: it is static, cylindrically symmetric and of Petrov class D.
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Geometry of the de-Sitter universe
International Journal of Theoretical Physics, 1974By making use of the fact that the de-Sitter metric corresponds to a hyperquadric in a five-dimensional flat space, it is shown that the three Robertson-Walker metrics for empty spacetime and positive cosmological constant, corresponding to 3-space of positive, negative and zero curvative, are geometrically equivalent.
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Particles and Fields on the de Sitter Universe
AIP Conference Proceedings, 2007In this paper we will give a short introduction to the geometry of the de Sitter universe and describe an approach to de Sitter Quantum Field Theory based on the complexification of the de Sitter manifold. We will also present some recent results about the stability of de Sitterian “particles” that have been obtained in a continuing collaboration with ...
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2012
In this work we analyze the development of de Sitter-Fantappie Relativity by analyzing, particularly, its applications to cosmology. The cosmological applications seem to be interesting since they resolve many problems of the standard cosmology. In this scenario the space flatness is linked to the observer geometry and it is independent from the ...
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In this work we analyze the development of de Sitter-Fantappie Relativity by analyzing, particularly, its applications to cosmology. The cosmological applications seem to be interesting since they resolve many problems of the standard cosmology. In this scenario the space flatness is linked to the observer geometry and it is independent from the ...
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Stability of de Sitter and anti-de Sitter universes and canonical superenergy tensors
AIP Conference Proceedings, 2013Recently some authors have proven that the anti-de Sitter spacetime is unstable under small perturbations. In our talk we present arguments which show that also the ordinary de Sitter spacetime is unstable. Our arguments are based on the calculation of the superenergy of the de Sitter spacetime.
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