Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the propagation of gravitational waves in strong magnetic fields   The propagation of gravitational waves is explored in the cosmological
context. It is explicitly demonstrated that the propagation of gravitational
waves could be influenced by the medium. It is shown that in the thermal
radiation, the propagation of gravitational waves in general relativity is
different from that in the scalar-tensor theory. The propagation of
gravitational waves is investigated in the uniform magnetic field. As a result,
it is found that cosmic magnetic fields could influence on the propagation of
gravitational waves to non-negligible extent. The corresponding estimation for
the spiral galaxy NGC 6946 effect is made.

16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
0
The categories of this paper are: hep-ph
10
The categories of this paper are: q-bio
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
17
The categories of this paper are: q-fin
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat