Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On the differentiability of the solution to an equation with drift and
  fractional diffusion   We consider an equation with drift and either critical or supercritical
fractional diffusion. Under a regularity assumption for the vector field that
is marginally stronger than what is required for Holder continuity of the
solutions, we prove that the solution becomes immediately differentiable with
Holder continuous derivatives. Therefore, the solutions to the equation are
classical.

0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess
37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
27
The categories of this paper are: comp-gas
25
The categories of this paper are: patt-sol
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
15
The categories of this paper are: nucl-ex
6
The categories of this paper are: astro-ph
24
The categories of this paper are: dg-ga
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
28
The categories of this paper are: alg-geom