Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Hydrogen atom in phase space: The Wigner representation   We have found an effective method of calculating the Wigner function, being a
quantum analogue of joint probability distribution of position and momentum,
for bound states of nonrelativistic hydrogen atom. The formal similarity
between the eigenfunctions of nonrelativistic hydrogen atom in the momentum
representation and Klein-Gordon propagators has allowed the calculation of the
Wigner function for an arbitrary bound state of the hydrogen atom. These Wigner
functions for some low lying states are depicted and discussed.

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The categories of this paper are: chao-dyn
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The categories of this paper are: patt-sol
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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
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The categories of this paper are: math-ph
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The categories of this paper are: solv-int
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The categories of this paper are: stat
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The categories of this paper are: dg-ga
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The categories of this paper are: bayes-an
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The categories of this paper are: supr-con
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The categories of this paper are: math
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The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
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The categories of this paper are: nlin