Instruct: Identify the main and secondary category of Arxiv papers based on the titles
Query: Criteria for flatness and injectivity
13
The categories of this paper are: quant-ph
16
The categories of this paper are: stat
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
17
The categories of this paper are: q-fin
20
The categories of this paper are: acc-phys
19
The categories of this paper are: eess
26
The categories of this paper are: bayes-an
22
The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
31
The categories of this paper are: ao-sci
28
The categories of this paper are: alg-geom
3
The categories of this paper are: physics
6
The categories of this paper are: astro-ph