Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Callias-type operators in $C^\ast$-algebras and positive scalar
  curvature on noncompact manifolds   A Dirac-type operator on a complete Riemannian manifold is of Callias-type if
its square is a Schr\"{o}dinger-type operator with a potential uniformly
positive outside of a compact set. We develop the theory of Callias-type
operators twisted with Hilbert $C^\ast$-module bundles and prove an index
theorem for such operators. As an application, we derive an obstruction to the
existence of complete Riemannian metrics of positive scalar curvature on
noncompact spin manifolds in terms of closed submanifolds of codimension-one.

11
The categories of this paper are: hep-lat
28
The categories of this paper are: alg-geom
6
The categories of this paper are: astro-ph
14
The categories of this paper are: math-ph
24
The categories of this paper are: dg-ga
9
The categories of this paper are: nlin
26
The categories of this paper are: bayes-an
18
The categories of this paper are: econ
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
25
The categories of this paper are: patt-sol
29
The categories of this paper are: funct-an
30
The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
1
The categories of this paper are: cs
31
The categories of this paper are: ao-sci