Speaker: Prof. Anthony Quas (Victoria) http://www.math.uvic.ca/faculty/aquas/ Time: Friday, Nov. 16, ***12NOON--1PM***(not the usual time) Room: RC-4082, Red Centre Building, UNSW Lunch with speaker: ***after the talk*** (not the usual plan). For Sydney staff and students, if there are more than one of you commute together, please feel free to take a taxi. The round trip is covered by school colloquium fund and you just need to give the receipt to me. I’ll be back towards the end of this month and you could leave the receipt in my mail box in 707A (with your name on it). ----------------------------------------------- Title: Low Complexity Alpern Lemmas: How Can You Tile a Floor With a Mixture of Metric and Imperial Tiles? Abstract: in Ergodic Theory, one is often interested in constructing maps between pairs of systems. A common approach to this is based on ``cutting orbits into pieces". These pieces should ideally be simply described. I will describe some theorems of this type, indicating how they are used and talk about recent work with Bryna Kra and Ayse Sahin, where we study the case of actions of R^d. Along the way, we discuss the possible tilings of an infinite plane with 1ft x 1ft tiles; and with 1m x 1m tiles. ----------------------------------------------- Joint Colloquium web site: http://www.maths.usyd.edu.au/u/SemConf/JointColloquium/index.html