Events for 11/09/2009 from all calendars
Algebraic Geometry Seminar
Time: 3:00PM - 4:00PM
Location: MILN 216
Speaker: Gregg Musiker, MIT
Title: Positivity results for cluster algebras arising from surfaces
Abstract: This talk will start by introducing the cluster algebras of Fomin and Zelevinsky with principal coefficients, and work of Fomin, Shapiro, and Thurston to realize these from triangulated surfaces. Then I will explain our result giving combinatorial formulas for cluster variables in any cluster algebra arisng from a triangulated surface, include those with punctures. This proves the positivity conjecture of Fomin and Zelevinsky for all such cluster algebras (which, by Felikson-Shapiro-Tumarkin, comprise "almost all" of the skew-symmetric cluster algebras of finite mutation type). This is joint work with Lauren Williams and Ralf Schiffler.
URL: Link
Algebra and Combinatorics Seminar
Time: 3:00PM - 3:50PM
Location: MILN 216
Speaker: Gregg Musiker, MIT
Title: TBA, joint with Algebraic Geometry Seminar
Center for Approximation Theory Seminar
Time: 3:05PM - 4:00PM
Location: 317 Milner Hall
Speaker: Aaron Bailey, Texas A&M University
Title: Frames of exponential functions and interpolation in Paley-Wiener space
Graduate Tea
Time: 3:30PM - 4:00PM
Location: Blocker 627
Applied Math Seminar
Time: 4:00PM - 5:00PM
Location: BLOC 627
Speaker: Dr. Anatoly Svidzinsky, Dept. of Physics, Texas A&M University
Title: Vector Theory of Gravity in Minkowski Space-Time: Flat Universe Without Black Holes
Abstract: Einstein theory of general relativity is based on the principle of equivalence and assumption that gravity is a tensor field. I will discuss an alternative theory of gravity which is also based on the principle of equivalence but assumes that gravity, similarly to all other fundamental interactions, is described by a vector field in Minkowski space-time. The vector theory is free of black holes and also passes available tests. Equations of the vector theory have exact analytical solution for arbitrary static mass distribution. For cosmology the present equations give essentially the same evolution of the Universe as general relativity. Predictions of the vector theory can be tested within next few years making more accurate measurement of the time delay of radar signal traveling near the Sun or by resolving the supermassive object at the center of our Galaxy.