The degree condition in Llarull's theorem on scalar curvature rigidity
Differential Geometry
2026-04-17 v2
Abstract
Llarull's scalar curvature rigidity theorem states that a 1-Lipschitz map from a closed connected Riemannian spin manifold with scalar curvature to the standard sphere is an isometry if the degree of is nonzero. We investigate if one can replace the condition by the weaker condition that is surjective. The answer turns out to be "no" for but "yes" for . If we replace the scalar curvature by Ricci curvature, the answer is "yes" in all dimensions.
Keywords
Cite
@article{arxiv.2507.05459,
title = {The degree condition in Llarull's theorem on scalar curvature rigidity},
author = {Christian Baer and Rudolf Zeidler},
journal= {arXiv preprint arXiv:2507.05459},
year = {2026}
}
Comments
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