Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Operations on categories of modules are given by Schur functors   Let $k$ be a commutative $\mathbb{Q}$-algebra. We study families of functors
between categories of finitely generated $R$-modules which are defined for all
commutative $k$-algebras $R$ simultaneously and are compatible with base
changes. These operations turn out to be Schur functors associated to
$k$-linear representations of symmetric groups. This result is closely related
to Macdonald's classification of polynomial functors.

24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
3
The categories of this paper are: physics
25
The categories of this paper are: patt-sol
1
The categories of this paper are: cs
15
The categories of this paper are: nucl-ex
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
36
The categories of this paper are: cmp-lg
28
The categories of this paper are: alg-geom
7
The categories of this paper are: hep-th
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con