Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analytical solution of the radiative transfer equation for polarized
  light   A new formalism is introduced for the transfer of polarized radiation. Stokes
parameters are shown to be four-vectors in a Minkowski-like space and, most
strikingly, the radiative transfer equation (RTE) turns out to be an
infinitesimal transformation under the Poincare (plus dilatations) group. A
solution to the transfer equation as a finite element of this group is
proposed.

26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
11
The categories of this paper are: hep-lat
0
The categories of this paper are: hep-ph
29
The categories of this paper are: funct-an
2
The categories of this paper are: math
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
31
The categories of this paper are: ao-sci
30
The categories of this paper are: q-alg
4
The categories of this paper are: cond-mat
21
The categories of this paper are: adap-org
16
The categories of this paper are: stat