Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Instabilities in two flavor quark matter   I discuss briefly the instabilities of two flavor quark matter, paying
attention to the gradient instability which develops in the g2SC phase in the
Goldstone $U(1)_A$ sector.

6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
12
The categories of this paper are: nucl-th
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
33
The categories of this paper are: plasm-ph
26
The categories of this paper are: bayes-an
10
The categories of this paper are: q-bio
25
The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph
13
The categories of this paper are: quant-ph
14
The categories of this paper are: math-ph