Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vacuum polarization by a magnetic flux of special rectangular form   We consider the ground state energy of a spinor field in the background of a
square well shaped magnetic flux tube. We use the zeta- function regularization
and express the ground state energy as an integral involving the Jost function
of a two dimensional scattering problem. We perform the renormalization by
subtracting the contributions from first several heat kernel coefficients. The
ground state energy is presented as a convergent expression suited for
numerical evaluation. We discuss corresponding numerical calculations. Using
the uniform asymptotic expansion of the special functions entering the Jost
function we are able to calculate higher order heat kernel coefficients.

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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: patt-sol
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The categories of this paper are: adap-org
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The categories of this paper are: physics
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The categories of this paper are: funct-an
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The categories of this paper are: supr-con
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-bio
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The categories of this paper are: alg-geom
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The categories of this paper are: math-ph
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The categories of this paper are: math
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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