Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Electron-phonon interaction effects on the direct gap transitions of
  nanoscale Si films
24
The categories of this paper are: dg-ga
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
19
The categories of this paper are: eess
21
The categories of this paper are: adap-org
30
The categories of this paper are: q-alg
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
0
The categories of this paper are: hep-ph
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
17
The categories of this paper are: q-fin