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: Benjamin Weiss, The Hebrew University of Jerusalem Title: On "a curious conjugacy invariant" of Halmos Date: Monday, November 19 Time: 14:30 Place: Schreiber 309 Abstract: One of the problems that Halmos posed at the end of his classic lectures on ergodic theory concerns a curious conjugacy invariant that he suggested might distinguish between ergodic toral automorphisms. I will describe this invariant and report on some recent results of A. Quas and T. Soo on the ergodic universality of toral automorphisms which relate to this invariant. In addition I will indicate an alternative argument which will suffice for the application to the Halmos problem. 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@post.tau.ac.il>