Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Absolutely continuous spectrum for the isotropic Maxwell operator with
  coefficients that are periodic in some directions and decay in others
33
The categories of this paper are: plasm-ph
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
30
The categories of this paper are: q-alg