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arXiv · 1704.03865

Super-expanders and warped cones

Damian Sawicki
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Abstract

For a Banach space $X$, we show that any family of graphs quasi-isometric to levels of a warped cone $\mathcal O_ΓY$ is an expander with respect to $X$ if and only if the induced $Γ$-representation on $L^2(Y;X)$ has a spectral gap. This provides examples of graphs that are an expander with respect to all Banach spaces of non-trivial type.

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Damian Sawicki. 2019-09-26. Super-expanders and warped cones. https://doi.org/10.5802/aif.3373

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