Einstein's equations are known to lead to the formation of black holes and spacetime singularities. This appears to be a manifestation of the mathematical phenomenon of finite-time blowup: a formation of singularities from regular initial data. We present a simple hyperbolic system of two semi-linear equations inspired by the Einstein equations. We explore a class of solutions to this system wh...

In this work, the solution of the Einstein equations for a slowly rotating black hole with Born-Infeld charge is obtained. Geometrical properties and horizons of this solution are analyzed. The conditions when the ADM mass (as in the nonlinear static cases) and the ADM angular momentum of the system have been modified by the non linear electromagnetic field of the black hole, are considered.

We consider the spacetimes corresponding to static Global Monopoles with interior boundaries corresponding to a Black Hole Horizon and analyze the behavior of the appropriate ADM mass as a function of the horizon radius rH . We find that for small enough rH , this mass is negative as in the case of the regular global monopoles, but that for large enough rH the mass becomes positive encountering...

We study a static, spherically symmetric system of (2j + 1) massive Dirac particles, each having angular momentum j, j = 1, 2, . . . , in a classical gravitational and SU(2) Yang-Mills field. We show that for any black hole solution of the associated Einstein-Dirac-Yang/Mills equations, the spinors must vanish identically outside of the event horizon. e-print archive: http://xxx.lanl.gov/gr-qc/...

In this work, the solution of the Einstein equations for a slowly rotating black hole with BornInfeld charge is obtained. Geometrical properties and horizons of this solution are analyzed. The conditions when the ADM mass (as in the nonlinear static cases) and the ADM angular momentum of the system have been modified by the non linear electromagnetic field of the black hole, are considered. PAC...

We utilize Møller’s and Einstein’s energy-momentum complexes in order to explicitly evaluate the energy distributions associated with the two-dimensional “Schwarzschild” and “Reissner-Nordström” black hole backgrounds. While Møller’s prescription provides meaningful physical results, Einstein’s prescription fails to do so in the aforementioned gravitational backgrounds. These results hold for a...

In this work we study the asymptotically flat, static, and spherically symmetric black-hole solutions of the theory described by the action

We study the formation and stability of regular black holes by employing a thin shell approximation to the dynamics of collapsing magnetic monopoles. The core deSitter region of the monopole is matched across the shell to a Reissner-Nordstrom exterior. We find static configurations which are nonsingular black holes and also oscillatory trajectories about these static points that share the same ...

We discuss some of the drawbacks of using event horizons to define black holes and suggest ways in which black holes can be described without event horizons, using trapping horizons. We show that these trapping horizons give rise to thermodynamic behavior and possibly Hawking radiation too. This raises the issue of whether the event horizon or the trapping horizon should be seen as the true bou...

It is by now clear that the naive rule for the entropy of a black hole, (entropy) = 1/4 (area of event horizon), is violated in many interesting cases. Indeed, several authors have recently conjectured that in general the entropy of a dirty black hole might be given purely in terms of some surface integral over the event horizon of that black hole. A formal proof of this conjecture, using Loren...