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arXiv · 2112.04825

Torsion Obstructions to Positive Scalar Curvature

Misha Gromov·Bernhard Hanke
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Abstract

We study obstructions to the existence of Riemannian metrics of positive scalar curvature on closed smooth manifolds arising from torsion classes in the integral homology of their fundamental groups. As an application, we construct new examples of manifolds which do not admit positive scalar curvature metrics, but whose Cartesian products admit such metrics.

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Misha Gromov, Bernhard Hanke. 2021-12-09. Torsion Obstructions to Positive Scalar Curvature. https://doi.org/10.3842/sigma.2024.069

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