Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Negative Pressure and Naked Singularities in Spherical Gravitational
  Collapse   Assuming the weak energy condition, we study the nature of the non-central
shell-focussing singularity which can form in the gravitational collapse of a
spherical compact object in classical general relativity. We show that if the
radial pressure is positive, the singularity is covered by a horizon. For
negative radial pressures, the singularity will be covered if the ratio of
pressure to the density is greater than -1/3 and naked if this ratio is $\leq
-1/3$.

9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
4
The categories of this paper are: cond-mat
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
26
The categories of this paper are: bayes-an
13
The categories of this paper are: quant-ph