Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Short wave length approximation of a boundary integral operator for
  homogeneous and isotropic elastic bodies   We derive a short wave length approximation of a boundary integral operator
for two-dimensional isotropic and homogeneous elastic bodies of arbitrary
shape. Trace formulae for elastodynamics can be deduced in this way from first
principles starting directly from Navier-Cauchy's equation.

3
The categories of this paper are: physics
18
The categories of this paper are: econ
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
25
The categories of this paper are: patt-sol
2
The categories of this paper are: math
35
The categories of this paper are: mtrl-th
1
The categories of this paper are: cs
28
The categories of this paper are: alg-geom
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph