Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Pairs of diagonal quadratic forms and linear correlations among sums of
  two squares   For suitable pairs of diagonal quadratic forms in 8 variables we use the
circle method to investigate the density of simultaneous integer solutions and
relate this to the problem of estimating linear correlations among sums of two
squares.

27
The categories of this paper are: comp-gas
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
26
The categories of this paper are: bayes-an
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
34
The categories of this paper are: chem-ph
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin