Zobrazeno 1 - 10
of 28
pro vyhledávání: '"Bernal, Antonio N."'
Autor:
Bernal, Antonio N., Janssen, Bert, Jimenez-Cano, Alejandro, Orejuela, Jose Alberto, Sanchez, Miguel, Sanchez-Moreno, Pablo
Publikováno v:
Phys.Lett. B768 (2017) 280-287
We study the most general solution for affine connections that are compatible with the variational principle in the Palatini formalism for the Einstein-Hilbert action (with possible minimally coupled matter terms). We find that there is a family of s
Externí odkaz:
http://arxiv.org/abs/1606.08756
In a recent article, M. Tegmark poses the hypothesis that our known universe is a ``baggage free'' mathematical structure among many other possible ones, which also correspond to other physical universes --Mathematical Universe Hypothesis, MUH. Natur
Externí odkaz:
http://arxiv.org/abs/0803.0944
Autor:
Bernal, Antonio N., Sánchez, Miguel
Publikováno v:
Class.Quant.Grav. 24 (2007) 745-750
The classical definition of {\em global hyperbolicity} for a spacetime $(M,g)$ comprises two conditions: (A) compactness of the diamonds $J^+(p)\cap J^-(q)$, and (B) strong causality. Here we show that condition (B) can be replaced just by causality.
Externí odkaz:
http://arxiv.org/abs/gr-qc/0611138
Autor:
Bernal, Antonio N., Sánchez, Miguel
Publikováno v:
Lett.Math.Phys. 77 (2006) 183-197
Recently, folk questions on the smoothability of Cauchy hypersurfaces and time functions of a globally hyperbolic spacetime M, have been solved. Here we give further results, applicable to several problems: (1) Any compact spacelike acausal submanifo
Externí odkaz:
http://arxiv.org/abs/gr-qc/0512095
Autor:
Bernal, Antonio N., Sánchez, Miguel
This paper has been withdrawn because the new one gr-qc/0512095 includes all its results (as well as those in gr-qc/0507018), in a clearer way.
Comment: This paper has been withdrawn; the new paper gr-qc/0512095 replaces both, the present one an
Comment: This paper has been withdrawn; the new paper gr-qc/0512095 replaces both, the present one an
Externí odkaz:
http://arxiv.org/abs/gr-qc/0511016
Autor:
Bernal, Antonio N., Sánchez, Miguel
This paper has been withdrawn because the new one gr-qc/0512095 includes all its results (as well as those in gr-qc/0511016) in a clearer way.
Comment: This paper has been withdrawn; the new paper gr-qc/0512095 replaces both, the present one and
Comment: This paper has been withdrawn; the new paper gr-qc/0512095 replaces both, the present one and
Externí odkaz:
http://arxiv.org/abs/gr-qc/0507018
Autor:
Bernal, Antonio N., Sánchez, Miguel
Geroch's theorem about the splitting of globally hyperbolic spacetimes is a central result in global Lorentzian Geometry. Nevertheless, this result was obtained at a topological level, and the possibility to obtain a metric (or, at least, smooth) ver
Externí odkaz:
http://arxiv.org/abs/gr-qc/0404084
Autor:
Bernal, Antonio N., Sánchez, Miguel
Publikováno v:
Commun.Math.Phys. 257 (2005) 43-50
The folk questions in Lorentzian Geometry, which concerns the smoothness of time functions and slicings by Cauchy hypersurfaces, are solved by giving simple proofs of: (a) any globally hyperbolic spacetime $(M,g)$ admits a smooth time function $\tau$
Externí odkaz:
http://arxiv.org/abs/gr-qc/0401112
Autor:
Bernal, Antonio N., Sánchez, Miguel
Publikováno v:
Commun.Math.Phys. 243 (2003) 461-470
Given a globally hyperbolic spacetime $M$, we show the existence of a {\em smooth spacelike} Cauchy hypersurface $S$ and, thus, a global diffeomorphism between $M$ and $\R \times S$.
Comment: Minor tipographical corrections; 12 pages, Latex; to
Comment: Minor tipographical corrections; 12 pages, Latex; to
Externí odkaz:
http://arxiv.org/abs/gr-qc/0306108
Autor:
Bernal, Antonio N., Sánchez, Miguel
Publikováno v:
J.Math.Phys. 44 (2003) 1129-1149
The following three geometrical structures on a manifold are studied in detail: (1) Leibnizian: a non-vanishing 1-form $\Omega$ plus a Riemannian metric $\h$ on its annhilator vector bundle. In particular, the possible dimensions of the automorphism
Externí odkaz:
http://arxiv.org/abs/gr-qc/0211030