Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Systems Exactly   Contents:
  1 Frustrated quantum spin systems
  1.1 The Pyrochlore checkerboard
  1.2 Singlets in reflection symmetric spin systems
  2 Wehrl entropy of Bloch coherent states
  2.1 Conjectures of Wehrl and Lieb
  2.2 Proof of Lieb's conjecture for low spin
  3 Symmetries of the Hubbard model
  4 Quantum integrable systems
  4.1 Twisted quantum Lax equations
  4.2 Face algebras and Ruijsenaars models
  5 Noncommutative gauge theory
  5.1 Gauge theory on noncommutative spaces
  5.2 Seiberg-Witten map and Kontsevich formality, Born-Infeld action in the
intermediate picture
  5.3 Nonabelian noncommutative gauge fields

28
The categories of this paper are: alg-geom
32
The categories of this paper are: atom-ph
10
The categories of this paper are: q-bio
24
The categories of this paper are: dg-ga
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
6
The categories of this paper are: astro-ph
8
The categories of this paper are: hep-ex
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
34
The categories of this paper are: chem-ph
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat
23
The categories of this paper are: solv-int
18
The categories of this paper are: econ