Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the Precise Determination of the Fermi Coupling Constant from the
  Muon Lifetime   The determination of the Fermi coupling constant, G_F, is examined in the
light of recently calculated 2-loop QED corrections and planned experiments to
measure the muon lifetime to a level below 1ppm. The methods used in the
calculation of the QED corrections are described in detail. Sources of the
dominant theoretical and experimental uncertainties are identified. Finally the
incorporation of G_F into analyses using the full electroweak Standard Model is
discussed.

33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
13
The categories of this paper are: quant-ph
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
25
The categories of this paper are: patt-sol
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
32
The categories of this paper are: atom-ph