Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Free Energy and Equation of State of Ising-like Magnet Near the Critical
  Point   The description of a three-dimensional Ising-like magnet in the presence of
an external field in the vicinity of the critical point by the collective
variables method is proposed. Using the renormalization group transformations,
the scaling region size is defined as a function of temperature and field. The
obtained expressions for the free energy, equation of state and susceptibility
allow one to analyse their dependence on microscopic parameters of the system.
The critical exponents of the correlation length and order parameter are
calculated as well. The results agree qualitatively with ones obtained within
the framework of the parametric representation of the equation of state and
Monte-Carlo simulations. The calculations do not involve any parametrization,
phenomenological assumptions and adjustable parameters. The approach can be
extended to models with a multicomponent order parameter.

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The categories of this paper are: chem-ph
18
The categories of this paper are: econ
22
The categories of this paper are: chao-dyn
13
The categories of this paper are: quant-ph
0
The categories of this paper are: hep-ph
35
The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg
2
The categories of this paper are: math
4
The categories of this paper are: cond-mat
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
33
The categories of this paper are: plasm-ph
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs