Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Global existence for a coupled wave system related to the Strauss
  conjecture   A coupled system of semilinear wave equations is considered, and a small data
global existence result related to the Strauss conjecture is proved. Previous
results have shown that one of the powers may be reduced below the critical
power for the Strauss conjecture provided the other power sufficiently exceeds
such. The stability of such results under asymptotically flat perturbations of
the space-time where an integrated local energy decay estimate is available is
established.

13
The categories of this paper are: quant-ph
10
The categories of this paper are: q-bio
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
34
The categories of this paper are: chem-ph
4
The categories of this paper are: cond-mat
28
The categories of this paper are: alg-geom