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arXiv · 1002.3879

Hilbert space compression for free products and HNN-extensions

Dennis Dreesen
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Abstract

Given the Hilbert space compression of two groups, we find bounds on the Hilbert space compression of their free product. We also investigate the Hilbert space compression of an HNN-extension of a group relative to a finite normal subgroup or a finite index subgroup.

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Dennis Dreesen. 2010-02-22. Hilbert space compression for free products and HNN-extensions. https://arxiv.org/abs/1002.3879

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