Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Transverse spin waves in isotropic ferromagnets   The comparison of transverse spin wave spectra and its attenuation in
Heisenberg ferromagnet and in ferromagnetic Fermi liquid as well in polarized
Fermi liquid is undertaken. The transverse spin waves frequency in polarized
paramagnetic Fermi liquid as well in a Fermi liquid with spontaneous
magnetization is found to be proportional to the square of the wave vector with
complex diffusion coefficient such that the damping has a finite value
proportional to the scattering rate of quasiparticles at T=0.
  This behavior of polarized Fermi liquid contrasts with the behavior of
Heisenberg ferromagnet in hydrodynamic regime where the transverse spin wave
attenuation appears in terms proportional to the wave vector in fourth power.
  The reactive part of diffusion coefficient in paramagnetic state at T=0
proves to be inversely proportional to magnetization whereas in ferromagnetic
state it is directly proportional to magnetization. The dissipative part of
diffusion coefficient at T=0 in paramagnetic state is polarization independent,
whereas in ferromagnetic state it is proportional to square of magnetization.
Moreover, the spin wave spectrum in ferromagnetic Fermi liquid proves to be
unstable that demonstrates the difficulty of the Fermi liquid description of
itinerant ferromagnetism.

9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
30
The categories of this paper are: q-alg
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
3
The categories of this paper are: physics
29
The categories of this paper are: funct-an
21
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
11
The categories of this paper are: hep-lat
1
The categories of this paper are: cs
5
The categories of this paper are: gr-qc
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The categories of this paper are: bayes-an
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The categories of this paper are: hep-ex