Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Monotonicity of the optimal perimeter in isoperimetric problems on
  ${\mathbb{Z}}^{k} \times {\mathbb{N}}^{d}$
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
3
The categories of this paper are: physics
18
The categories of this paper are: econ
27
The categories of this paper are: comp-gas
32
The categories of this paper are: atom-ph
8
The categories of this paper are: hep-ex
0
The categories of this paper are: hep-ph
4
The categories of this paper are: cond-mat
14
The categories of this paper are: math-ph
29
The categories of this paper are: funct-an
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
20
The categories of this paper are: acc-phys
34
The categories of this paper are: chem-ph