Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Separating expansion from contraction: generalized TOV condition, LTB
  models with pressure and $\Lambda$CDM   We discuss the existence of a dividing shell separating expanding and
collapsing regions in spherically symmetric solutions with pressure. We obtain
gauge invariant conditions relating not only the intrinsic spatial curvature of
the shells to the ADM mass, but also a function of the pressure which we
introduce that generalises the Tolman-Oppenheimer-Volkoff equilibrium
condition, in the framework of a 3+1 spacetime splitting. We consider the
particular case of a Lema\^itre-Tolman-Bondi dust models with a cosmological
constant (a $\Lambda$-CDM model) as an example of our results.

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The categories of this paper are: math
15
The categories of this paper are: nucl-ex
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
16
The categories of this paper are: stat
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
35
The categories of this paper are: mtrl-th
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an