A simple description of Thompson’s group F
نویسندگان
چکیده
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 ⊗ A A; then F is the group of automorphisms of A.
منابع مشابه
Commensurations and Subgroups of Finite Index of Thompson’s Group F
Thompson’s groups have been extensively studied since their introduction by Thompson in the 1960s, despite the fact that Thompson’s account [7] appeared only in 1980. They have provided examples of infinite finitely presented simple groups, as well as some other interesting counterexamples in group theory (see for example, Brown and Geoghegan [3]). Cannon, Floyd and Parry [4] give an excellent ...
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