Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-Abelian evolution of electromagnetic waves in a weakly anisotropic
  inhomogeneous medium   A theory of electromagnetic wave propagation in a weakly anisotropic smoothly
inhomogeneous medium is developed, based on the quantum-mechanical
diagonalization procedure applied to Maxwell equations. The equations of motion
for the translational (ray) and intrinsic (polarization) degrees of freedom are
derived ab initio. The ray equations take into account the optical Magnus
effect (spin Hall effect of photons) as well as trajectory variations owing to
the medium anisotropy. Polarization evolution is described by the precession
equation for the Stokes vector. In generic case, the evolution of waves turns
out to be non-Abelian: it is accompanied by mutual conversion of the normal
modes and periodic oscillations of the ray trajectories analogous to electron
zitterbewegung. The general theory is applied to examples of wave evolution in
media with circular and linear birefringence.

36
The categories of this paper are: cmp-lg
15
The categories of this paper are: nucl-ex
35
The categories of this paper are: mtrl-th
33
The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
19
The categories of this paper are: eess
25
The categories of this paper are: patt-sol
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
28
The categories of this paper are: alg-geom
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
32
The categories of this paper are: atom-ph