Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Four-loop Dyson-Schwinger-Johnson anatomy   Dyson-Schwinger equations are used to evaluate the 4-loop anomalous
dimensions of quenched QED in terms of finite, scheme-independent, 3-loop
integrals. Three of the results serve as strong checks of terms from
scheme-dependent 4-loop QCD calculations. The fourth, for the anomalous
dimension of $\bar\psi\sigma_{\mu\nu}\psi$, was previously known only to 2-loop
order. The 4-loop beta function has 24 unambiguous terms. Two of the simplest
give $\beta_4=\frac13(22-160)=-46$. The rational, $\zeta_3$ and $\zeta_5$ parts
of the other 22 miraculously sum to zero. Vertex anomalous dimensions have 40
terms, with no dramatic cancellations. Our methods come from work by the late
Kenneth Johnson, done more than 30 years ago. They are entirely free of the
subtractions and infrared rearrangements of later methods.

36
The categories of this paper are: cmp-lg
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
32
The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
19
The categories of this paper are: eess
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The categories of this paper are: mtrl-th
2
The categories of this paper are: math
16
The categories of this paper are: stat
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org