165 citations · 1.1k across the 59 of their papers we have counts for
23 papers · 1 filter
On the significance of the stress-energy tensor in Finsler spacetimes
Miguel Ángel Javaloyes, Miguel Sánchez, Fidel F. Villaseñor
We revisit the physical arguments which lead to the definition of the stress-energy tensor in the Lorentz-Finsler setting starting at classical Relativity. Both the sta…
Globally hyperbolic spacetimes: slicings, boundaries and counterexamples
Miguel Sánchez
The Cauchy slicings for globally hyperbolic spacetimes and their relation with the causal boundary are surveyed and revisited, starting at the seminal conformal boundary constructi…
Foundations of Finsler spacetimes from the Observers' Viewpoint
Antonio Bernal, Miguel Ángel Javaloyes, Miguel Sánchez
Physical foundations for relativistic spacetimes are revisited, in order to check at what extent Finsler spacetimes lie in their framework. Arguments based on inertial observers (a…
Structure of globally hyperbolic spacetimes with timelike boundary
L. Aké Hau, José L. Flores, Miguel Sánchez
Globally hyperbolic spacetimes with timelike boundary are the natural class of spacetimes where regular boundary conditions (eventually asym…
Ehlers-Kundt Conjecture about Gravitational Waves and Dynamical Systems
José L. Flores, Miguel Sánchez
Ehlers-Kundt conjecture is a physical assertion about the fundamental role of plane waves for the description of gravitational waves. Mathematically, it becomes equivalent to a pro…
On the (non-)uniqueness of the Levi-Civita solution in the Einstein-Hilbert-Palatini formalism
Antonio N. Bernal, Bert Janssen, Alejandro Jimenez-Cano +3
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 possibl…
A note on stability and Cauchy time functions
Miguel Sánchez
Since the solution of the so-called folk problems of smoothability, there has been a special interest in the properties of classical time and volume functions of spacetimes. Here w…
A note on the existence of standard splittings for conformally stationary spacetimes
Miguel Angel Javaloyes, Miguel Sánchez
Let be a spacetime which admits a complete timelike conformal Killing vector field . We prove that splits globally as a standard conformastationary spacetime wit…
Physics from scratch. Letter on M. Tegmark's ``The Mathematical Universe''
Antonio N. Bernal, Miguel Sánchez, Francisco José Soler Gil
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 o…
Recent progress on the notion of global hyperbolicity
Miguel Sánchez
Global hyperbolicity is a central concept in Mathematical Relativity. Here, we review the different approaches to this concept explaining both, classical approaches and recent resu…
Some remarks on Causality Theory and Variational Methods in Lorentzian manifolds
Miguel Sanchez
In this conference published in 1997 some problems on the geodesics of a Lorentzian manifold concerning causality and infinite-dimensional variational methods, are pointed out. Eve…
The causal boundary of wave-type spacetimes
José Luis Flores, Miguel Sánchez
A complete and systematic approach to compute the causal boundary of wave-type spacetimes is carried out. The case of a 1-dimensional boundary is specially analyzed and its critica…
A note on causally simple and globally hyperbolic spacetimes
Miguel Sanchez
This paper has been withdrawn because the part concerning the definition of global hyperbolicity has already been included in an expanded and clearer way in gr-qc/0611138. The rema…
The causal hierarchy of spacetimes
E. Minguzzi, M. Sanchez
The full causal ladder of spacetimes is constructed, and their updated main properties are developed. Old concepts and alternative definitions of each level of the ladder are revis…
Cauchy hypersurfaces as levels of time and temporal functions
Antonio N. Bernal, Miguel Sánchez
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.
Further results on the smoothability of Cauchy hypersurfaces and Cauchy time functions
Antonio N. Bernal, Miguel Sánchez
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, appli…
A note on the extendability of compact hypersurfaces to smooth Cauchy hypersurfaces
Antonio N. Bernal, Miguel Sánchez
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.
Causal hierarchy of spacetimes, temporal functions and smoothness of Geroch's splitting. A revision
Miguel Sánchez
After the heroic epoch of Causality Theory, problems concerning the smoothability of time functions and Cauchy hypersurfaces remained as unanswered folk questions. Just recently so…
On the geometry of pp-wave type spacetimes
José Luis Flores, Miguel Sánchez
Global geometric properties of product manifolds , endowed with a metric type (where $<\cdot,…
Smooth globally hyperbolic splittings and temporal functions
Antonio N. Bernal, Miguel Sánchez
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 le…
Leibnizian, Galilean and Newtonian structures of spacetime
Antonio N. Bernal, Miguel Sánchez
The following three geometrical structures on a manifold are studied in detail: (1) Leibnizian: a non-vanishing 1-form plus a Riemannian metric $\h$ on its annhilator vector bu…
On General Plane Fronted Waves. Geodesics
A. M. Candela, J. L. Flores, Miguel Sanchez
A general class of Lorentzian metrics, , , with any Riemannian manifold, is introduced in order to generalize classic…
Fundamental units of length and time
A. N. Bernal, M. P. Lopez, M. Sanchez
Ideal rods and clocks are defined as an infinitesimal symmetry of the spacetime. Since no a priori geometric structure is considered, all the possible models of spacetime are obtai…