Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Crossing the Phantom divide line in the Chaplygin gas model   The role of the interaction in reaching and crossing the phantom divide line
in the Chaplygin gas model is discussed. We obtain some necessary properties of
the interaction that allow the model to arrive at or cross the phantom divide
line. We show that these properties put some conditions on the ratio of dark
matter to dark energy density in the present epoch.

11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph
17
The categories of this paper are: q-fin
18
The categories of this paper are: econ
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
26
The categories of this paper are: bayes-an
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
12
The categories of this paper are: nucl-th
8
The categories of this paper are: hep-ex