Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Phase transition in O_2   We exhibit a one-parameter group of automorphism on the Cuntz-algebra O_2
such that the simplex of KMS states changes abruptly at a certain critical
temperature from infinitely many to one, and then none. The factor types of the
extremal KMS states are also determined.

9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
11
The categories of this paper are: hep-lat
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
6
The categories of this paper are: astro-ph
0
The categories of this paper are: hep-ph
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
33
The categories of this paper are: plasm-ph
21
The categories of this paper are: adap-org
13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int