Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Commutator of Electric Charge and Magnetic Flux   Here one can find a derivation of the commutator of the charge and magnetic
flux in a superconducting circuit containing a Josephson junction from the
commutation relation of quantum-field operators of electric field and vector
potential. A commutator of the fluxes of electric and magnetic fields passing
through two interlinked loops in vacuum is also evaluated and physical
interpretation of the commutator is discussed.

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The categories of this paper are: math-ph
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The categories of this paper are: cs
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The categories of this paper are: gr-qc
0
The categories of this paper are: hep-ph
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The categories of this paper are: solv-int
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The categories of this paper are: cond-mat
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The categories of this paper are: funct-an
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The categories of this paper are: nucl-ex
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The categories of this paper are: eess
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The categories of this paper are: nlin
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: stat
2
The categories of this paper are: math
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The categories of this paper are: econ