Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: How to reconcile Information theory and Gibbs-Herz entropy for inverted
  populated systems
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
5
The categories of this paper are: gr-qc
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
0
The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
11
The categories of this paper are: hep-lat
17
The categories of this paper are: q-fin