Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Effects of the Backward Scattering in Two-Dimensional Electron System
20
The categories of this paper are: acc-phys
3
The categories of this paper are: physics
13
The categories of this paper are: quant-ph
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
12
The categories of this paper are: nucl-th
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
19
The categories of this paper are: eess
9
The categories of this paper are: nlin
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
16
The categories of this paper are: stat
25
The categories of this paper are: patt-sol
11
The categories of this paper are: hep-lat