Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Some Properties of Correlations of Quantum Lattice Systems in Thermal
  Equilibrium   Simple proofs of uniqueness of the thermodynamic limit of KMS states and of
the decay of equilibrium correlations are presented for a large class of
quantum lattice systems at high temperatures. New quantum correlation
inequalities for general Heisenberg models are described. Finally, a simplified
derivation of a general result on power-law decay of correlations in 2D quantum
lattice systems with continuous symmetries is given, extending results of Mc
Bryan and Spencer for the 2D classical XY model.

9
The categories of this paper are: nlin
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
13
The categories of this paper are: quant-ph
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
36
The categories of this paper are: cmp-lg
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
18
The categories of this paper are: econ