Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Darwin-Foldy term and proton charge radius   In this contribution we study the Dirac equation for a finite size proton in
an external electric field with explicit introduction of Dirac-Pauli form
factors. Our aim is twofold. On the one hand, we wish to study whether our
conclusions regarding the exact cancellation between Dirac form factor and
Foldy term contributions occurring for the neutron still hold for the proton.
On the other hand, we wish to clearly illustrate some of the specific features
of the description of a composite particle like the proton with the Dirac
equation.

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The categories of this paper are: cond-mat
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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
11
The categories of this paper are: hep-lat
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex
28
The categories of this paper are: alg-geom
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The categories of this paper are: acc-phys
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The categories of this paper are: quant-ph
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The categories of this paper are: math-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: q-fin
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The categories of this paper are: cs
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The categories of this paper are: patt-sol
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The categories of this paper are: plasm-ph
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The categories of this paper are: q-alg