Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: On co-amenability for groups and von Neumann algebras   We first show that co-amenability does not pass to subgroups, answering a
question asked by Eymard in 1972. We then address co-amenability for von
Neumann algebras, describing notably how it relates to the former.

17
The categories of this paper are: q-fin
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
30
The categories of this paper are: q-alg
16
The categories of this paper are: stat
28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys