Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Liquid-Gas Coexistence and Critical Behavior in Boxed Pseudo-Fermi
  Matter   A schematic model is presented that allows one to study the behavior of
interacting pseudo-Fermi matter locked in a thermostatic box. As a function of
the box volume and temperature, the matter is seen to show all of the familiar
charactersitics of a Van der Waals gas, which include the coexistence of two
phases under certain circumstances and the presence of a critical point.

4
The categories of this paper are: cond-mat
22
The categories of this paper are: chao-dyn
7
The categories of this paper are: hep-th
6
The categories of this paper are: astro-ph
26
The categories of this paper are: bayes-an
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
37
The categories of this paper are: supr-con
28
The categories of this paper are: alg-geom
1
The categories of this paper are: cs
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat
20
The categories of this paper are: acc-phys