The analytical structure of the difference between the static vacuum solution in the nonsymmetric gravitational theory (NGT) and the Schwarzschild solution of Einstein’s gravitational theory (EGT) is studied. It is proved that a smooth matching of the solutions does not exist in the range 0 < r ≤ 2M , for any non-zero values of the parameters M and s of the NGT solution. This means that one can...

Gravitational collapse is one of the most fruitful subjects in gravitational physics. It is well known that singularity formation is inevitable in complete gravitational collapse. It was conjectured that such a singularity should be hidden by horizons if it is formed from generic initial data with physically reasonable matter fields. Many possible counterexamples to this conjecture have been pr...

We consider here the gravitational collapse of a spherically symmetric inhomogeneous dust cloud described by the Tolman-Bondi models. By studying a general class of these models, we find that the end state of the collapse is either a black hole or a naked singularity, depending on the parameters of the initial density distribution, which are ρc, the initial central density of the massive body, ...

We examine here the relevance of the initial state of a collapsing dust cloud towards determining it's final fate in the course of a continuing gravitational collapse. It is shown that given any arbitrary matter distribution M (r) for the cloud at the initial epoch, there is always a freedom to choose rest of the initial data, namely the initial velocities of the collapsing spherical shells, so...

We present the first three-dimensional (3D) calculations of the gravitational-wave emission in the collapse of uniformly rotating stars to black holes. The initial models are polytropes which are dynamically unstable and near the mass-shedding limit. The waveforms have been extracted using a gauge-invariant approach and reflect the properties of both the initial stellar models and of newly prod...

Miguel Alcubierre, Gabrielle Allen, Bernd Brügmann, Gerd Lanfermann, Edward Seidel, Wai-Mo Suen, and Malcolm Tobias (1) Max-Planck-Institut für Gravitationsphysik, Schlaatzweg 1, 14473 Potsdam, Germany (2) National Center for Supercomputing Applications, Beckman Institute, 405 N. Mathews Ave., Urbana, IL 61801 (3) Department of Physics, Washington University, St. Louis, MO 63130 (4) Physics Dep...

We investigate here spherically symmetric gravitational collapse in a spacetime with an arbitrary number of dimensions and with a general type I matter field, which is a broad class that includes most of the physically reasonable matter forms. We show that given the initial data for matter in terms of the initial density and pressure profiles at an initial surface t = ti from which the collapse...

In this paper we investigate the critical collapse of an ultrarelativistic perfect fluid with the equation of state P = (Γ − 1)ρ in the limit of Γ → 1. We calculate the limiting continuously self similar (CSS) solution and the limiting scaling exponent by exploiting self-similarity of the solution. We also solve the complete set of equations governing the gravitational collapse numerically for ...

By using the most general form of Einstein equations for General Relativistic (GTR) spherical collapse of an isolated fluid having arbitrary equation of state and radiation transport properties, we show that they obey a Global Constraint, 2GM(r, t)/R(r, t)c2 ≤ 1, where R is the “invariant circumference radius”, t is the comoving time, and M(r, t) is the gravitational mass enclosed within a como...

We consider the emission of gravitational waves in the two proposed models for the collapse of a massive star to a black hole: the prompt collapse, in which nearly all the star collapses to a black hole in a dynamical time scale, and the delayed collapse, in which a light black hole, or a neutron star, which subsequently accretes matter, forms due to the fall-back achieving, in the neutron star...