Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the determination of Moving Boundaries for Hyperbolic Equations   We consider wave equations in domains with time-dependent boundaries (moving
obstacles) contained in a fixed cylinder for all time. We give sufficient
conditions for the determination of the moving boundary from the Cauchy data on
part of the boundary of the cylinder. We also study the related problem of
accessibility of the moving boundary by time-like curves from the boundary of
the cylinder.

21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
7
The categories of this paper are: hep-th
24
The categories of this paper are: dg-ga
36
The categories of this paper are: cmp-lg
0
The categories of this paper are: hep-ph
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph
28
The categories of this paper are: alg-geom