Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A phenomenological theory of phase transitions in high T_{c}
  superconductors   A phenomenological theory is suggested to explain the experimentally
discovered "paramagnetic peculiarity" and the unconventional change of the
energetic state of a layers of high T_{c} of Y-Ba-Cu-O in the vicinity of the
phase transition. The physical conditions are found under which these
peculiarities are revealed. It is shown that the suggested theory qualitatively
describes the experimental data.

36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
14
The categories of this paper are: math-ph
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
15
The categories of this paper are: nucl-ex
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg