Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Matching heavy-quark fields in QCD and HQET at three loops   The relation between the heavy-quark field in QCD and the corresponding field
in HQET is derived up to three loops, and to all orders in the large-$\beta_0$
limit. The corresponding relation between the QED electron field and the
Bloch--Nordsieck one is gauge invariant to all orders. We also prove that the
$\bar{\text{MS}}$ anomalous dimension of the QED electron field depends on the
gauge parameter only at one loop.

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The categories of this paper are: adap-org
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The categories of this paper are: acc-phys
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The categories of this paper are: supr-con
7
The categories of this paper are: hep-th
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
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The categories of this paper are: cond-mat
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The categories of this paper are: astro-ph
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The categories of this paper are: math-ph
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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
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The categories of this paper are: eess
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The categories of this paper are: q-fin