Tel Aviv University Dear all, This week at the Horowitz seminar on Probability, Ergodic Theory and Dynamical Systems at Tel Aviv University we are happy to have: Speaker: Noga Alon, Tel Aviv University Title: The chromatic number of random Cayley graphs Date: Monday, June 4 Time: 14:30 Place: Schreiber 309 Abstract: The study of random Cayley graphs of finite groups is related to the investigation of Expanders and to problems in combinatorial Number Theory and in Information Theory. I will discuss this topic, focusing on the question of estimating the chromatic number of a random Cayley graph of a given group with a prescribed number of generators. One representative result is the fact that if p is a large prime and S is a random subset of at most 0.5 log_2 p members of Z_p, then the chromatic number of the Cayley graph of Z_p with respect to S is almost surely exactly 3. Of possible additional interest is the talk in the Statistics seminar on Tuesday, see <http://www.math.tau.ac.il/~ruheller/Stat%20seminar.htm> Best regards, Ron Seminar webpage: <http://www.math.tau.ac.il/~peledron/Horowitz_seminar/Horowitz_seminar.html> --------------------------------------------------------- Technion Math Net-2 (TECHMATH2) Editor: Michael Cwikel <techm@math.technion.ac.il> Announcement from: Ron Peled <peledron@gmail.com>