Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A nonseparable amenable operator algebra which is not isomorphic to a
  C*-algebra   It has been a longstanding problem whether every amenable operator algebra is
isomorphic to a (necessarily nuclear) C*-algebra. In this note, we give a
nonseparable counterexample. The existence of a separable counterexample
remains an open problem. We also initiate a general study of unitarizability of
representations of amenable groups in C*-algebras and show that our method
cannot produce a separable counterexample.

28
The categories of this paper are: alg-geom
22
The categories of this paper are: chao-dyn
6
The categories of this paper are: astro-ph
1
The categories of this paper are: cs
36
The categories of this paper are: cmp-lg
19
The categories of this paper are: eess
14
The categories of this paper are: math-ph
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
17
The categories of this paper are: q-fin
9
The categories of this paper are: nlin
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
7
The categories of this paper are: hep-th
20
The categories of this paper are: acc-phys