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arXiv · 2412.13914

Isometric rigidity of $L^2$-spaces with manifold targets

David Lenze
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Abstract

We describe the isometry group of $L^2(\Omega, M)$ for Riemannian manifolds $M$ of dimension at least two with irreducible universal cover. We establish a rigidity result for the isometries of these spaces: any isometry arises from an automorphism of $\Omega$ and a family of isometries of $M$, distinguishing these spaces from the classical $L^2(\Omega)$. Additionally, we prove that these spaces lack irreducible factors and that two such spaces are isometric if and only if the underlying manifolds are.

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David Lenze. 2024-12-18. Isometric rigidity of $L^2$-spaces with manifold targets. https://arxiv.org/abs/2412.13914

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