Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Existence of travelling-wave solutions and local well-posedness of the
  Fowler equation   We study the existence of travelling-waves and local well-posedness in a
subspace of $C_b^1(\mathbb{R})$ for a nonlinear evolution equation recently
proposed by Andrew C. Fowler to study the dynamics of dunes.

35
The categories of this paper are: mtrl-th
16
The categories of this paper are: stat
15
The categories of this paper are: nucl-ex
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
28
The categories of this paper are: alg-geom
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
23
The categories of this paper are: solv-int
29
The categories of this paper are: funct-an
4
The categories of this paper are: cond-mat
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph