Title: Monochromatic sums and products and recurrence
Speaker: Joel Moreira
Speaker Info: Northwestern University
Brief Description:
Special Note:
Abstract:
An open problem in Ramsey theory asks whether in any finite partition of the natural numbers it is possible to find a quadruple of the form {x,y,x+y,xy} in a single cell of the partition. One can study this and related problems from a dynamical perspective by transferring them into questions about recurrence for actions of the semigroup of the affine transformations over N. Using this approach, I will present a proof that any finite partition of the natural numbers yields a triple {x,x+y,xy} in a single cell.Date: Tuesday, April 18, 2017