Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Positive scalar curvature and an equivariant Callias-type index theorem
  for proper actions   For a proper action by a locally compact group $G$ on a manifold $M$ with a
$G$-equivariant Spin-structure, we obtain obstructions to the existence of
complete $G$-invariant Riemannian metrics with uniformly positive scalar
curvature. We focus on the case where $M/G$ is noncompact. The obstructions
follow from a Callias-type index theorem, and relate to positive scalar
curvature near hypersurfaces in $M$. We also deduce some other applications of
this index theorem. If $G$ is a connected Lie group, then the obstructions to
positive scalar curvature vanish under a mild assumption on the action. In that
case, we generalise a construction by Lawson and Yau to obtain complete
$G$-invariant Riemannian metrics with uniformly positive scalar curvature,
under an equivariant bounded geometry assumption.

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The categories of this paper are: adap-org
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: q-fin
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The categories of this paper are: stat
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The categories of this paper are: alg-geom
8
The categories of this paper are: hep-ex
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The categories of this paper are: dg-ga
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The categories of this paper are: econ
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The categories of this paper are: chao-dyn
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The categories of this paper are: funct-an
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The categories of this paper are: cond-mat
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-lat