Can gravitational collapse sustain singularity-free trapped surfaces?
Abstract
In singularity generating spacetimes both the out-going and in-going expansions of null geodesic congruences and should become increasingly negative without bound, inside the horizon. This behavior leads to geodetic incompleteness which in turn predicts the existence of a singularity. In this work we inquire on whether, in gravitational collapse, spacetime can sustain singularity-free trapped surfaces, in the sense that such a spacetime remains geodetically complete. As a test case, we consider a well known solution of the Einstien Field Equations which is Schwarzschild-like at large distances and consists of a fluid with a equation of state near . By following both the expansion parameters and across the horizon and into the black hole we find that both and have turning points inside the trapped region. Further, we find that deep inside the black hole there is a region (that includes the black hole center) which is not trapped. Thus the trapped region is bounded both from outside and inside. The spacetime is geodetically complete, a result which violates a condition for singularity formation. It is inferred that in general if gravitational collapse were to proceed with a fluid formation, the resulting black hole may be singularity-free.
Cite
@article{arxiv.0708.2360,
title = {Can gravitational collapse sustain singularity-free trapped surfaces?},
author = {Manasse R. Mbonye and Demosthenes Kazanas},
journal= {arXiv preprint arXiv:0708.2360},
year = {2008}
}
Comments
17 pages, 3 figures, accepted for publication in International Journal of Modern Physics D