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An abstract characterization of Thompson's group F

Marcelo Fiore·Tom Leinster
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Abstract

We show that Thompson's group F is the symmetry group of the "generic idempotent". That is, take the monoidal category freely generated by an object A and an isomorphism A \otimes A --> A; then F is the group of automorphisms of A.

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Marcelo Fiore, Tom Leinster. 2005-08-30. An abstract characterization of Thompson's group F. https://arxiv.org/abs/math/0508617

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