Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Perturbative QCD theory (includes our knowledge of alpha_s)   Following the logic of the great Chinese warrior-philosopher Master Sun Tzu,
  "The rules of the military are five: measurement, assessment, calculation,
comparison and victory", we address the problem of what we know, think we know,
and think about the QCD coupling.

20
The categories of this paper are: acc-phys
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
29
The categories of this paper are: funct-an
26
The categories of this paper are: bayes-an
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph
36
The categories of this paper are: cmp-lg
11
The categories of this paper are: hep-lat
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin