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arXiv · 1605.04830

Characterization of the Haagerup property for residually amenable groups

Kamil Orzechowski
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Abstract

The notions of a box family and fibred cofinitely-coarse embedding are introduced. The countable, residually amenable groups satisfying the Haagerup property are then characterized as those possessing a box family that admits a fibred cofinitely-coarse embedding into a Hilbert space. This is a generalization of a result of X. Chen, Q. Wang and X. Wang on residually finite groups.

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Kamil Orzechowski. 2016-05-16. Characterization of the Haagerup property for residually amenable groups. https://arxiv.org/abs/1605.04830

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