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The BTZ Black Hole as a Lorentz-Flat Geometry
(2014)
It is shown that 2 + 1dimensional anti-de Sitter spacetimes are Lorentz-flat. This means, in particular, that any simply-connected patch of the BTZ black hole solution can be endowed with a Lorentz connection that is locally ...
The BTZ black hole as a Lorentz-flat geometry
(Elsevier, 2015)
The BTZ black hole as a Lorentz-flat geometry
(Elsevier, 2015)
Kant e a geometriaKant and the geometry
([s.n.], 2016)
Characterization of the PSD of activated carbons from peach stones for separation of combustion gas mixtures
(Springer, 2011-02)
Controlled series of microporous carbons were prepared through chemical activation with phosphoric acid from peach stones as the precursor material, corresponding to different preparation conditions. Adsorption isotherms ...
Pre-inflation: Origin of the Universe from a topological phase transition
(Elsevier Science, 2017-08)
I study a model which describes the birth of the universe using a global topological phase transition with a complex manifold where the time, τ, is considered as a complex variable. Before the big bang τ is a purely imaginary ...
Dynamo effects and geometrical origin of the alpha term in affine theory of gravity
(Maik Nauka Publishing / Springer SBM, 2017-12)
Dynamo effect is considered in the context of an Unified field theoretical model based in affine geometries. We show that there exists an analog “α-term” in the equations that has a purely geometric origin, in sharp contrast ...
A hybrid symbolic-numerical approach to the center-focus problem
(2017-09-01)
We propose a new hybrid symbolic-numerical approach to the center-focus problem. The method allowed us to obtain center conditions for a three-dimensional system of differential equations, which was previously not possible ...
Sobre a geometria diferencial de certas frontais no 3-espaço Euclidiano
(Universidade Estadual Paulista (Unesp), 2022-08-31)
Este trabalho busca estudar a geometria diferencial de algumas classes de superfícies com singularidades que não são necessariamente não degeneradas ou frentes. Dentre elas, estudamos a superfície singular D4, que é uma ...