Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On T-violation signals originating from magnetic orders through double
  exchange mechanism   The photon self energy tensor in a crystal with double exchange and
ferromagnetic or canting magnetic orders is analyzed at zero temperature with
emphasis on the signal of the time-reversal invariance breaking. Three
comparable contributions, spin susceptibility, local magnetic field and
spin-orbit coupling are estimated and the prospect of their experimental
detection is discussed.

29
The categories of this paper are: funct-an
2
The categories of this paper are: math
9
The categories of this paper are: nlin
19
The categories of this paper are: eess
5
The categories of this paper are: gr-qc
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
17
The categories of this paper are: q-fin
14
The categories of this paper are: math-ph
13
The categories of this paper are: quant-ph
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
10
The categories of this paper are: q-bio
1
The categories of this paper are: cs
22
The categories of this paper are: chao-dyn
35
The categories of this paper are: mtrl-th