# Seminar at SMU Delhi

September 15, 2015 (Tuesday) , 3:30 PM at Webinar
Speaker: Nishant Chandgotia, University of British Columbia
Title: Entropy Minimality and Four-Cycle Free Graphs
Abstract of Talk
A topological dynamical system (X,T) is said to be entropy minimal if all closed T-invariant subsets of X have entropy strictly less than (X,T). In this talk we will discuss the entropy minimality of a class of topological dynamical systems which appear as the space of graph homomorphisms from Z^d to graphs without four cycles; for instance, we will see why the space of 3-colourings of Z^d is entropy minimal even though it does not have any of the nice topological mixing properties. Along the way, I will try to indicate some connections of such problems with probability and algebraic topology.