Charting Islands of Stability with Multioscillators in anti-de Sitter space.

We propose the existence of an infinite-parameter family of solutions in anti-de Sitter (AdS) that oscillate on any number of noncommensurate frequencies. Some of these solutions appear stable when perturbed, and we suggest that they can be used to map out the AdS "islands of stability." By numerically constructing two-frequency solutions and exploring their parameter space, we find that both collapse and noncollapse are generic scenarios near AdS.

Collapse and Nonlinear Instability of AdS Space with Angular Momentum.

We present a numerical study of rotational dynamics in AdS_{5} with equal angular momenta in the presence of a complex doublet scalar field. We determine that the endpoint of gravitational collapse is a Myers-Perry black hole for high energies and a hairy black hole for low energies. We investigate the time scale for collapse at low energies E, keeping the angular momenta J∝E in anti-de Sitter (AdS) length units.

Black Hole Formation in Randall-Sundrum II Braneworlds.

We present the first numerical study of the full dynamics of a braneworld scenario, working within the framework of the single brane model of Randall and Sundrum. In particular, we study the process of gravitational collapse driven by a massless scalar field which is confined to the brane. Imposing spherical symmetry on the brane, we show that the evolutions of sufficiently strong initial configurations of the scalar field result in black holes that have finite extension into the bulk.

Ultrarelativistic particle collisions.

We present results from numerical solution of the Einstein field equations describing the head-on collision of two solitons boosted to ultrarelativistic energies. We show, for the first time, that at sufficiently high energies the collision leads to black hole formation, consistent with hoop-conjecture arguments. This implies that the nonlinear gravitational interaction between the kinetic energy of the solitons causes gravitational collapse, and that arguments for black hole formation in super-Planck scale particle collisions are robust.

Critical collapse of a complex scalar field with angular momentum.

We report a new critical solution found at the threshold of axisymmetric gravitational collapse of a complex scalar field with angular momentum. To carry angular momentum the scalar field cannot be axisymmetric; however, its azimuthal dependence is defined so that the resulting stress-energy tensor and spacetime metric are axisymmetric. The critical solution found is nonspherical, discretely self-similar with an echoing exponent Delta=0.