Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: $\nu =1/2$ Bilayer Tunnelling   Tunneling of electrons between two $\nu = 1/2$ quantum Hall parallel planes
is studied. In order to calculate the physical electron Green's function, the
Chern-Simons gauge field formalism is used, both in a perturbative many-body
calculation and in a semiclassical calculation. In contrast to recent
experiments, no gap in the physical electron density of states is found. A
conjecture is made that either perturbation theory about the mean field Fermi
liquid ground state is inadequate, or that disorder within the interplanar
barrier plays a role.

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The categories of this paper are: physics
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The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th
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The categories of this paper are: dg-ga
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The categories of this paper are: acc-phys
29
The categories of this paper are: funct-an
0
The categories of this paper are: hep-ph
9
The categories of this paper are: nlin
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The categories of this paper are: eess
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The categories of this paper are: atom-ph
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The categories of this paper are: q-alg
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The categories of this paper are: gr-qc
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The categories of this paper are: stat
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The categories of this paper are: q-fin
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The categories of this paper are: econ
26
The categories of this paper are: bayes-an