Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Nonreciprocal Scattering by PT-symmetric stack of the layers
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex
18
The categories of this paper are: econ
5
The categories of this paper are: gr-qc
21
The categories of this paper are: adap-org
2
The categories of this paper are: math
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
12
The categories of this paper are: nucl-th
28
The categories of this paper are: alg-geom