Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Gravitational Collapse of Gravitational Waves in 3D Numerical Relativity   We demonstrate that evolutions of three-dimensional, strongly non-linear
gravitational waves can be followed in numerical relativity, hence allowing
many interesting studies of both fundamental and observational consequences. We
study the evolution of time-symmetric, axisymmetric {\it and} non-axisymmetric
Brill waves, including waves so strong that they collapse to form black holes
under their own self-gravity. The critical amplitude for black hole formation
is determined. The gravitational waves emitted in the black hole formation
process are compared to those emitted in the head-on collision of two Misner
black holes.

33
The categories of this paper are: plasm-ph
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
13
The categories of this paper are: quant-ph
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
3
The categories of this paper are: physics
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs