Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Smooth Version of Johnson's Problem Concerning Derivations of Group
  Algebras   A description of the algebra of outer derivations of a group algebra of a
finitely presented discrete group is given in terms of the Cayley complex of
the groupoid of the adjoint action of the group. This task is a smooth version
of Johnson's problem concerning the derivations of a group algebra. It is shown
that the algebra of outer derivations is isomorphic to the group of the
one-dimensional cohomology with compact supports of the Cayley complex over the
field of complex numbers.

21
The categories of this paper are: adap-org
5
The categories of this paper are: gr-qc
7
The categories of this paper are: hep-th
34
The categories of this paper are: chem-ph
20
The categories of this paper are: acc-phys
8
The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
10
The categories of this paper are: q-bio
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
24
The categories of this paper are: dg-ga
1
The categories of this paper are: cs
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
6
The categories of this paper are: astro-ph