Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Finite-velocity diffusion on a comb   A Cattaneo equation for a comb structure is considered. We present a rigorous
analysis of the obtained fractional diffusion equation, and corresponding
solutions for the probability distribution function are obtained in the form of
the Fox $H$-function and its infinite series. The mean square displacement
along the backbone is obtained as well in terms of the infinite series of the
Fox $H$-function. The obtained solutions describe the transition from normal
diffusion to subdiffusion, which results from the comb geometry.

6
The categories of this paper are: astro-ph
23
The categories of this paper are: solv-int
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
33
The categories of this paper are: plasm-ph
7
The categories of this paper are: hep-th
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
3
The categories of this paper are: physics
1
The categories of this paper are: cs