Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On Neumann and oblique derivatives boundary conditions for nonlocal
  elliptic equations   Inspired by the penalization of the domain approach of Lions & Sznitman, we
give a sense to Neumann and oblique derivatives boundary value problems for
nonlocal, possibly degenerate elliptic equations. Two different cases are
considered: (i) homogeneous Neumann boundary conditions in convex, possibly
non-smooth and unbounded domains, and (ii) general oblique derivatives boundary
conditions in smooth, bounded, and possibly non-convex domains. In each case we
give apropriate definitions of viscosity solutions and prove uniqueness of
solutions of the corresponding boundary value problems. We prove that these
boundary value problems arise in the penalization of the domain limit from
whole space problems and obtain as a corollary the existence of solutions of
these problems.

26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
18
The categories of this paper are: econ
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
5
The categories of this paper are: gr-qc
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
27
The categories of this paper are: comp-gas
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
4
The categories of this paper are: cond-mat
1
The categories of this paper are: cs
34
The categories of this paper are: chem-ph