Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fine Boundary--Layer structure in Linear Transport Theory   This contribution identifies and characterizes a previously unrecognized
boundary--layer structure that occurs in the context of linear transport
theory, with an impact on the fields of Radiative Transfer and Neutron
Transport. The existence of this boundary layer structure, which governs the
interactions between different materials, or between a material and vacuum,
plays a critical role in a correct description of transport phenomena.
Additionally, the boundary--layer phenomenology explains and helps bypass
computational difficulties reported in the literature over the last several
decades.

27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
17
The categories of this paper are: q-fin
1
The categories of this paper are: cs
2
The categories of this paper are: math
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
16
The categories of this paper are: stat
13
The categories of this paper are: quant-ph
5
The categories of this paper are: gr-qc
3
The categories of this paper are: physics
14
The categories of this paper are: math-ph
30
The categories of this paper are: q-alg
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
12
The categories of this paper are: nucl-th