Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the gravitational fields created by the electromagnetic waves   We show that the Maxwell equations describing an electromagnetic wave are a
mathematical consequence of the Einstein equations for the same wave. This fact
is significant for the problem of the Einsteinian metrics corresponding to the
electromagnetic waves.

12
The categories of this paper are: nucl-th
36
The categories of this paper are: cmp-lg
37
The categories of this paper are: supr-con
34
The categories of this paper are: chem-ph
13
The categories of this paper are: quant-ph
32
The categories of this paper are: atom-ph
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
2
The categories of this paper are: math
19
The categories of this paper are: eess
18
The categories of this paper are: econ
21
The categories of this paper are: adap-org
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
17
The categories of this paper are: q-fin