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Gruppo di Logica e Geometria della Cognizione
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Key 1

Laver tables

Speaker:
Patrick Dehornoy (Université Caen-Normandie)
Quando:
17/02/2017 - 11:30
Dove:
Dipartimento di Matematica e Fisica, Aula 311 Largo San Leonardo Murialdo, 1
Abstract

Discovered (or invented?) by Richard Laver in the 1990s, the tables that are now known as Laver tables are finite structures obeying the self-distributivity law x(yz)=(xy)(xz). Although their construction is totally explicit, some of their combinatorial properties are (so far) established only using unprovable set theoretical axioms, a quite unusual and paradoxical situation. We shall explain the construction of Laver tables, their connection with set theory, and their potential applications in low-dimensional topology via the recent computation of some associated cocycles.



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