arXiv · 1810.11015
We prove that every countably infinite group with Kazhdan's property (T) has cost 1, answering a well-known question of Gaboriau. It remains open if they have fixed price 1.
Tom Hutchcroft, Gábor Pete. 2018-10-25. Kazhdan groups have cost 1. https://arxiv.org/abs/1810.11015
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