Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Logarithmically enhanced Euler-Heisenberg Lagrangian contribution to the
  electron gyromagnetic factor   Contrary to what was previously believed, two-loop radiative corrections to
the $g$-factor of an electron bound in a hydrogen-like ion at
$\mathcal{O}\left(\alpha^2 (Z\alpha)^5\right)$ exhibit logarithmic enhancement.
This previously unknown contribution is due to a long-distance light-by-light
scattering amplitude. Taking an effective field theory approach, and using the
Euler-Heisenberg Lagrangian, we find $\Delta g = -\left( \frac{\alpha}{\pi}
\right)^2\left(Z\alpha\right)^5 \frac{56 \pi}{135}\ln Z\alpha$.

20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
17
The categories of this paper are: q-fin
16
The categories of this paper are: stat
31
The categories of this paper are: ao-sci
15
The categories of this paper are: nucl-ex
32
The categories of this paper are: atom-ph
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org