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arXiv · 1812.03712

Embedding of $RCD^*(K,N)$ spaces in $L^2$ via eigenfunctions

Luigi Ambrosio·Shouhei Honda·Jacobus W. Portegies·David Tewodrose
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Abstract

In this paper we study the family of embeddings $Φ_t$ of a compact $RCD^*(K,N)$ space $(X,d,m)$ into $L^2(X,m)$ via eigenmaps. Extending part of the classical results by Bérard, Bérard-Besson-Gallot, known for closed Riemannian manifolds, we prove convergence as $t\downarrow 0$ of the rescaled pull-back metrics $Φ_t^*g_{L^2}$ in $L^2(X,m)$ induced by $Φ_t$. Moreover we discuss the behavior of $Φ_t^*g_{L^2}$ with respect to measured Gromov-Hausdorff convergence and $t$. Applications include the quantitative $L^p$-convergence in the noncollapsed setting for all $p<\infty$, a result new even for closed Riemannian manifolds and Alexandrov spaces.

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Luigi Ambrosio, Shouhei Honda, Jacobus W. Portegies, David Tewodrose. 2021-02-18. Embedding of $RCD^*(K,N)$ spaces in $L^2$ via eigenfunctions. https://arxiv.org/abs/1812.03712

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