Monday, April 24, 16:00, 8.122 (colloquium)

Patrick Dehornoy (Caen)
Set theory fifty years after Cohen.

Abstract:
We present a few results of modern Set Theory, with a special emphasis on the Continuum Hypothesis and the possibility of solving the question after the well known negative results of Godel and Cohen, and on Laver tables, which are explicit finite structures, some simple combinatorial properties of which have so far only been proved using (unprovable) large cardinal axioms, a very paradoxical situation.