Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Generalized theory of spin fluctuations in itinerant electron magnets:
  crucial role of spin anharmonicity   The paper critically overviews the recent developments of the theory of spin
fluctuations (SF) in itinerant electron magnetism with particular emphasis on
spin-fluctuation coupling or spin anharmonicity. It is argued that the
conventional self-consistent renormalized (SCR) theory of spin fluctuations is
usually used aside of the range of its applicability actually defined by the
constraint of weak spin anharmonicity based on the random phase approximation
(RPA) arguments. An essential step in understanding SF in itinerant magnets
beyond RPA-like arguments was made recently within the soft-mode theory of SF
accounting for strong spin anharmonicity caused by zero-point SF. In the
present paper we generalize it to apply for a wider range of temperatures and
regimes of SF and show it to lead to qualitatively new results caused by
zero-point effects.

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The categories of this paper are: physics
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The categories of this paper are: math-ph
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The categories of this paper are: econ
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The categories of this paper are: dg-ga
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The categories of this paper are: quant-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: stat
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The categories of this paper are: hep-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
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The categories of this paper are: q-fin
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The categories of this paper are: astro-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: q-bio