Seminar Calendar
for events the day of Thursday, October 14, 2010.

.
events for the
events containing

Questions regarding events or the calendar should be directed to Tori Corkery.
    September 2010          October 2010          November 2010
Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa   Su Mo Tu We Th Fr Sa
1  2  3  4                   1  2       1  2  3  4  5  6
5  6  7  8  9 10 11    3  4  5  6  7  8  9    7  8  9 10 11 12 13
12 13 14 15 16 17 18   10 11 12 13 14 15 16   14 15 16 17 18 19 20
19 20 21 22 23 24 25   17 18 19 20 21 22 23   21 22 23 24 25 26 27
26 27 28 29 30         24 25 26 27 28 29 30   28 29 30
31


Thursday, October 14, 2010

Number Theory
1:00 pm   in 241 Altgeld Hall,  Thursday, October 14, 2010
 Del Edit Copy
Submitted by berndt.
 Kagan Kursungoz (Pennsylvania State University)A Generalization of Algorithm-Z with an ApplicationAbstract: We will review algorithm-Z, and show how it is used in proving the q-binomial theorem bijectively. Then we will describe a generalization with one additional parameter, and show how this is used in proving the q-Gauss summation formula bijectively. If time allows, we will give a small open problem, and discuss possibilities for future research. This is joint work with Ae Ja Yee.

Group Theory Seminar
1:00 pm   in 347 Altgeld Hall,  Thursday, October 14, 2010
 Del Edit Copy
Submitted by dsrobins.
 Derek Robinson (UIUC-Math)Recent Results on Generalized Baumslag-Solitar GroupsAbstract: A generalized Baumslag-Solitar group (or GBS-group) is the fundamental group of a graph of groups with infinite cyclic vertex and edge groups. We will review the background and recent results on GBS-groups, including the epsilon-invariant and its connections with the center and abelianization of a GBS-group.

Special Algebraic Geometry Seminar
2:00 pm   in 447 Altgeld,  Thursday, October 14, 2010
 Del Edit Copy
Submitted by nevins.
 Ian Shipman (University of Chicago)A Geometric Implementation of Orlov's TheoremAbstract: Consider a smooth Calabi-Yau hypersurface X in P^{N-1} defined by homogeneous equation W. A celebrated result of D. Orlov states that the derived bounded category of coherent sheaves on X is triangulated-equivalent to the homotopy category of graded matrix factorizations of W over C[x_1 , . . . , x_N ]. In this talk I will define the category of matrix factorizations and explain how to realize this equivalence using functors and categories that are sheaf-theoretical and avoids direct mention of the category of singularities. To accomplish this, we work with matrix factorizations over non-affine schemes in the framework of E. Segal. We confirm Knorrer periodicity and localization on the critical set of the potential and use these to get links in a chain of equivalences. Then we use Segal’s result relating matrix factorizations over inverse GIT quotients of an affine space to complete the chain of equivalences.

Commutative Algebra Seminar
3:00 pm   in 243 Altgeld Hall,  Thursday, October 14, 2010
 Del Edit Copy
Submitted by asecele2.
 Uwe Nagel (University of Kentucky)Buchsbaum modules and level algebrasAbstract: After reviewing the concept of Buchsbaum modules, we specialize it to simplicial complexes. Then we discuss the recently introduced class of Buchsbaum* complexes, which includes all triangulations of orientable topological manifolds. Relating Buchsbaum* complexes to level algebras, we provide new restrictions on the Hilbert functions and face vectors of such complexes.

Differential Geometry Seminar
3:00 pm   in 347 Altgeld Hall,  Thursday, October 14, 2010
 Del Edit Copy
Submitted by clein.
 Gabriele La Nave (UIUC Math)Finite time singularities of the Kahler-Ricci flow and symplectic reductions.Abstract: In the last few years, the Ricci flow has been used extensively (by Hamilton, Perelman et al.) as a powerful tool in the Geometric and Topological study of compact three-manifolds. The Ricci flow has been recently applied to study the geometry of compact Kaehler manifolds of arbitrary dimension in a manner that encompasses and geometrizes the Minimal Model Program of Birational Geometry. The major stumbling block for such a program is the formation of finite time singularities. In recent work with G. Tian, we propose a link between the Kaehler-Ricci flow and a new static equation of (degenerate) elliptic type on a manifold endowed with a holomorphically hamiltonian S^1-action. We then describe the singularity formation and the surgery necessary to bypass such singularities in one stroke as a variation of symplectic quotients. I will discuss the construction and some of the analysis that is behind solving the relevant equations.

Fall Department Faculty Meeting
4:00 pm   in 245 Altgeld Hall,  Thursday, October 14, 2010
 Del Edit Copy
Submitted by seminar.
 Fall Department Faculty MeetingAbstract: The Fall Department Faculty Meeting will be held from 4 to 5 p.m. on Thursday, October 14, 2010, in 245 Altgeld Hall. A reception will follow in the same room.