Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Magnetic tension and gravitational collapse   The gravitational collapse of a magnetised medium is investigated by studying
qualitatively the convergence of a timelike family of non-geodesic worldlines
in the presence of a magnetic field. Focusing on the field's tension we
illustrate how the winding of the magnetic forcelines due to the fluid's
rotation assists the collapse, while shear-like distortions in the distribution
of the field's gradients resist contraction. We also show that the relativistic
coupling between magnetism and geometry, together with the tension properties
of the field, lead to a magneto-curvature stress that opposes the collapse.
This tension stress grows stronger with increasing curvature distortion, which
means that it could potentially dominate over the gravitational pull of the
matter. If this happens, a converging family of non-geodesic lines can be
prevented from focusing without violating the standard energy conditions.

18
The categories of this paper are: econ
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
37
The categories of this paper are: supr-con
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
29
The categories of this paper are: funct-an
36
The categories of this paper are: cmp-lg