Department of Mathematics University of Haifa Special Colloquium Speaker: Dr. Yonatan Gutman Institut des Hautes Etudes Scientifiques Topic: A Juzvinskii Addition Theorem for Finitely Generated Free Group Actions Date: Friday, December 2, 2011 Place: Room 614 of the Science & Education Building, University of Haifa Time: 10:00 AM ==> Note special time and day!!! <=== Abstract The classical Juzvinskii Addition Theorem states that the entropy of an automorphism of a compact group decomposes along invariant subgroups. Thomas generalized the theorem to a skew-product setting. Using L. Bowen's f-invariant we prove the addition theorem for actions of finitely generated free groups on skew-products with compact totally disconnected groups or finitely dimensional Lie groups. The proof uses a Rokhlin-Abramov formula for the f-invariant. I will discuss examples. Joint work with Lewis Bowen. --------------------------------------------------------- Technion Math Net-2 (TECHMATH2) Editor: Michael Cwikel <techm@math.technion.ac.il> Announcement from: David Blanc <blanc@math.haifa.ac.il>