An Exotic Group with the Haagerup Property
نویسنده
چکیده
We prove the Haagerup property for an infinite discrete group constructed using surgery on a Euclidean Tits building of type Ã2. The group Γ./ studied in this paper is the fundamental group of a 2-dimensional cell complex V./ defined by gluing 13 faces along their boundaries respecting orientation and labelling as follows:
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