Speaker : Professor Bong Lian (Brandeis University)
Title : A Convexity Theorem and Delzant Spaces
Time : 2011-11-17 (Thu) 15:00 - 16:00
Place : Auditorium, 6 Floor, Institute of Mathematics (NTU Campus)
Abstract: The convexity theorem of Atiyah and Guillemin Sternberg says that for any connected compact manifold with a Hamiltonian torus T-action, the image of its moment map is the convex hull of the image of the fixed point set. We extend this theorem to certain singular spaces, and apply it to classify up to homeomorphisms those singular T-spaces of dimension 2 dim(T) having effective T-actions, generalizing a theorem of Delzant in the smooth case, and a theorem of Lerman-Tolman in the orbifold case. This is joint work with B. Song.