Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Mean first-passage time of surface-mediated diffusion in spherical
  domains
29
The categories of this paper are: funct-an
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
23
The categories of this paper are: solv-int
21
The categories of this paper are: adap-org
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
15
The categories of this paper are: nucl-ex
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
20
The categories of this paper are: acc-phys
17
The categories of this paper are: q-fin