Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Microscopic Functional Integral Theory of Quantum Fluctuations in
  Double-Layer Quantum Hall Ferromagnets   We present a microscopic theory of zero-temperature order parameter and
pseudospin stiffness reduction due to quantum fluctuations in the ground state
of double-layer quantum Hall ferromagnets. Collective excitations in this
systems are properly described only when interactions in both direct and
exchange particle-hole channels are included. We employ a functional integral
approach which is able to account for both, and comment on its relation to
diagrammatic perturbation theory. We also discuss its relation to Gaussian
fluctuation approximations based on Hubbard-Stratonovich-transformation
representations of interactions in ferromagnets and superconductors. We derive
remarkably simple analytical expressions for the correlation energy,
renormalized order parameter and renormalized pseudospin stiffness.

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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio
13
The categories of this paper are: quant-ph
36
The categories of this paper are: cmp-lg
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The categories of this paper are: dg-ga
27
The categories of this paper are: comp-gas
33
The categories of this paper are: plasm-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: econ
1
The categories of this paper are: cs
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The categories of this paper are: ao-sci
17
The categories of this paper are: q-fin
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The categories of this paper are: chao-dyn
34
The categories of this paper are: chem-ph
35
The categories of this paper are: mtrl-th
37
The categories of this paper are: supr-con