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arXiv · 2108.08506

Band width and the Rosenberg index

Yosuke Kubota
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Abstract

A Riemannian manifold is said to have infinite $\mathcal{KO}$-width if it admits an isometric immersion of an arbitrarily wide Riemannian band whose inward boundary has non-trivial higher index. In this paper we prove that if a closed spin manifold has inifinite $\mathcal{KO}$-width, then its Rosenberg index does not vanish. This gives a positive answer to a conjecture by R. Zeidler. We also prove its `multi-dimensional' generalization; if a closed spin manifold admit an isometric immersion of an arbitrarily wide cube-like domain whose lowest dimensional corner has non-trivial higher index, then the Rosenberg index of $M$ does not vanish.

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Yosuke Kubota. 2021-08-19. Band width and the Rosenberg index. https://arxiv.org/abs/2108.08506

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