Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the dynamical stability of quasi-toroidal differentially rotating
  neutron stars   We investigate the dynamical stability of relativistic, differentially
rotating, quasi-toroidal models of neutron stars through hydrodynamical
simulations in full general relativity. We find that all quasi-toroidal
configurations studied in this work are dynamically unstable against the growth
of non-axisymmetric modes. Both one-arm and bar mode instabilities grow during
their evolution. We find that very high rest mass configurations collapse to
form black holes. Our calculations suggest that configurations whose rest mass
is less than the binary neutron star threshold mass for prompt collapse to
black hole transition dynamically to spheroidal, differentially rotating stars
that are dynamically stable, but secularly unstable. Our study shows that the
existence of extreme quasi-toroidal neutron star equilibrium solutions does not
imply that long-lived binary neutron star merger remnants can be much more
massive than previously found. Finally, we find models that are initially
supra-Kerr ($J/M^2>1$) and undergo catastrophic collapse on a dynamical
timescale, in contrast to what was found in earlier works. However, cosmic
censorship is respected in all of our cases. Our work explicitly demonstrates
that exceeding the Kerr bound in rotating neutron star models does not imply
dynamical stability.

17
The categories of this paper are: q-fin
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
4
The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ