Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Blocks of group algebras are derived simple   A derived version of Maschke's theorem for finite groups is proved: the
derived categories, bounded or unbounded, of all blocks of the group algebra of
a finite group are simple, in the sense that they admit no nontrivial
recollements. This result is independent of the characteristic of the base
field.

20
The categories of this paper are: acc-phys
15
The categories of this paper are: nucl-ex
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
23
The categories of this paper are: solv-int
19
The categories of this paper are: eess
32
The categories of this paper are: atom-ph
5
The categories of this paper are: gr-qc
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
6
The categories of this paper are: astro-ph
18
The categories of this paper are: econ
29
The categories of this paper are: funct-an