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arXiv · 2310.05721

Stability of $L^2-$invariants on stratified spaces

Francesco Bei·Paolo Piazza·Boris Vertman
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Abstract

Let $\overline{M}$ be a compact smoothly stratified pseudo-manifold endowed with a wedge metric $g$. Let $\overline{M}_\Gamma$ be a Galois $\Gamma$-covering. Under additional assumptions on $\overline{M}$, satisfied for example by Witt pseudo-manifolds, we show that the $L^2$-Betti numbers and the Novikov-Shubin invariants are well defined. We then establish their invariance under a smoothly stratified, strongly stratum preserving homotopy equivalence, thus extending results of Dodziuk, Gromov and Shubin to these pseudo-manifolds.

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Francesco Bei, Paolo Piazza, Boris Vertman. 2023-10-09. Stability of $L^2-$invariants on stratified spaces. https://arxiv.org/abs/2310.05721

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