Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum Force in Superconductor   Transitions between states with continuous (called as classical state) and
discrete (called as quantum state) spectrum of permitted momentum values is
considered. The persistent current can exist along the ring circumference in
the quantum state in contrast to the classical state. Therefore the average
momentum can changes at the considered transitions. In order to describe the
reiterated switching into and out the quantum state an additional term is
introduced in the classical Boltzmann transport equation. The force inducing
the momentum change at the appearance of the persistent current is called as
quantum force. It is shown that dc potential difference is induced on ring
segments by the reiterated switching if the dissipation force is not
homogeneous along the ring circumference. The closing of the superconducting
state in the ring is considered as real example of the transition from
classical to quantum state

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The categories of this paper are: astro-ph
30
The categories of this paper are: q-alg
7
The categories of this paper are: hep-th
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
33
The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
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The categories of this paper are: solv-int
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The categories of this paper are: hep-ex
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The categories of this paper are: q-fin
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The categories of this paper are: econ
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The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th