Tel Aviv University Dear all, The Horowitz seminar renews its activity for the Spring semester this Monday. Please see our current schedule on the website below. This week we are happy to have: Speaker: Barak Weiss, Ben-Gurion University Title: The Mordell-Gruber spectrum and homogeneous dynamics. Date: Monday, March 5 Time: 14:30 Place: Schreiber 309 Abstract: Given a lattice in euclidean space, its Mordell constant is the supremum of the volumes (suitably normalized) of central symmetric boxes with sides parallel to the axes, containing no nonzero lattice points. This is a well-studied quantity in the geometry of numbers, and is invariant under the action of diagonal matrices on the space of lattices. In joint work with Uri Shapira, using dynamics of the diagonal group we obtain new results about the set of possible values of the Mordell constant (the so-called Mordell-Gruber spectrum). 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>