Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Landau Levels and Quantum Group   We find a quantum group structure in two-dimensional motions of a
nonrelativistic electron in a uniform magnetic field and in a periodic
potential. The representation basis of the quantum algebra is composed of
wavefunctions of the system. The quantum group symmetry commutes with the
Hamiltonian and is relevant to the Landau level degeneracy. The deformation
parameter $q$ of the quantum algebra turns out to be given by the fractional
filling factor $\nu=1/m$ ($m$ odd integer).

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The categories of this paper are: stat
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
24
The categories of this paper are: dg-ga
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
15
The categories of this paper are: nucl-ex
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The categories of this paper are: alg-geom
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The categories of this paper are: funct-an
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The categories of this paper are: patt-sol
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The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
22
The categories of this paper are: chao-dyn