Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum discrete $\phi ^4$ model at finite temperatures: the mean-field
  phase diagram   The quantum discrete $\phi ^4$ model at finite temperature is studied in the
mean-field approximation. The phase diagrams are obtained for a wide range of
the model parameters. The domains of applicability for the classical, quantum,
and order-disorder limits are determined. It is shown that a remarkable part of
the phase diagram is reproduced by the first quantum correction to the
classical result. Parameters of Sn$_2$P$_2$S$_6$, SrTiO$_3$, and KH$_2$PO$_4$
are placed in the phase diagram of the model.

21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
2
The categories of this paper are: math
9
The categories of this paper are: nlin
36
The categories of this paper are: cmp-lg
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
5
The categories of this paper are: gr-qc
18
The categories of this paper are: econ
28
The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
26
The categories of this paper are: bayes-an
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
10
The categories of this paper are: q-bio