Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Multi-travelling waves for the nonlinear klein-gordon equation   For the nonlinear Klein-Gordon equation in R 1+d , we prove the existence of
multi-solitary waves made of any number N of decoupled bound states. This
extends the work of C{\^o}te and Mu{\~n}oz (Forum Math. Sigma 2 (2014)) which
was restricted to ground states, as were most previous similar results for
other nonlinear dispersive and wave models.

3
The categories of this paper are: physics
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
7
The categories of this paper are: hep-th
26
The categories of this paper are: bayes-an
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
24
The categories of this paper are: dg-ga