Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Semi-classical Dirac vacuum polarisation in a scalar field   We study vacuum polarisation effects of a Dirac field coupled to an external
scalar field and derive a semi-classical expansion of the regu-larised vacuum
energy. The leading order of this expansion is given by a classical formula due
to Chin, Lee-Wick and Walecka, for which our result provides the first rigorous
proof. We then discuss applications to the non-relativistic large-coupling
limit of an interacting system, and to the stability of homogeneous systems.

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The categories of this paper are: q-alg
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The categories of this paper are: q-bio
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The categories of this paper are: plasm-ph
3
The categories of this paper are: physics
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The categories of this paper are: acc-phys
7
The categories of this paper are: hep-th
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The categories of this paper are: supr-con
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-ex
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The categories of this paper are: nlin
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The categories of this paper are: cmp-lg
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: bayes-an
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The categories of this paper are: chao-dyn
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The categories of this paper are: eess