Zobrazeno 1 - 10
of 25
pro vyhledávání: '"da Rocha, Jaime F. Villas"'
Autor:
Campista, M., Chan, R., da Silva, M. F. A., Goldoni, O., Satheeshkumar, V. H., da Rocha, Jaime F. Villas
Publikováno v:
Canadian Journal of Physics 98, 10 (2020)
The Einstein-Aether (EA) theory belongs to a class of modified gravity theories characterized by the introduction of a time-like unit vector field, called aether. In this scenario, a preferred frame arises as a natural consequence of a broken Lorentz
Externí odkaz:
http://arxiv.org/abs/1807.07553
Publikováno v:
In Futures January 2019 105:91-103
Publikováno v:
Astrophys. Spa. Sci. 337, 185-191, 2012
Using the conventional gravastar model, that is, an object constituted by two components where one of them is a massive infinitely thin shell and the other one is a de Sitter interior spacetime, we physically interpret a solution characterized by a z
Externí odkaz:
http://arxiv.org/abs/1004.2906
Publikováno v:
Phys.Lett.A367:423-430,2007
A two-component fluid representing dark energy is studied. One of the components has a polytropic form, while the other has a barotropic form. Exact solutions are obtained and the cosmological parameters are constrained using supernova type Ia data.
Externí odkaz:
http://arxiv.org/abs/astro-ph/0606171
Perturbed Self-Similar Massless Scalar Field in the Spacetimes with Circular Symmetry in 2+1 Gravity
Publikováno v:
Int.J.Mod.Phys.D14:1725-1738,2005
We present in this work the study of the linear perturbations of the 2+1-dimensional circularly symmetric solution, obtained in a previous work, with kinematic self-similarity of the second kind. We have obtained an exact solution for the perturbatio
Externí odkaz:
http://arxiv.org/abs/gr-qc/0505046
Publikováno v:
Int.J.Mod.Phys.D15:545-558,2006
The 2+1-dimensional geodesic circularly symmetric solutions of Einstein-massless-scalar field equations with negative cosmological constant are found and their local and global properties are studied. It is found that one of them represents gravitati
Externí odkaz:
http://arxiv.org/abs/gr-qc/0505045
We use Vaschy-Buckhingham Theorem as a systematic tool to build univocal n-dimensional extensions of the electric and gravitational fine structure constants and show that their ratio is dimensionally invariant. The results allow us to obtain the rela
Externí odkaz:
http://arxiv.org/abs/physics/0309040
Publikováno v:
Int.J.Mod.Phys. D12 (2003) 347-368
A class of solutions to Einstein field equations is studied, which represents gravitational collapse of thick spherical shells made of self-similar and shear-free fluid with heat flow. It is shown that such shells satisfy all the energy conditions, a
Externí odkaz:
http://arxiv.org/abs/gr-qc/0209067
Autor:
da Rocha, Jaime F. Villas
Publikováno v:
Int.J.Mod.Phys. D11 (2002) 113-124
A large class of Type II fluid solutions to Einstein field equations in N-dimensional spherical spacetimes is found, wich includes most of the known solutions. A family of the generalized collapsing Vaidya solutions with homothetic self-similarity, p
Externí odkaz:
http://arxiv.org/abs/gr-qc/0105095
The Riemann, Ricci and Einstein tensors for N-dimensional spherically symmetric spacetimes in various systems of coordinates are studied, and the general metric for conformally flat spacetimes is given. As an application, all the Friedmann-Robertson-
Externí odkaz:
http://arxiv.org/abs/gr-qc/9910109