Seminar Calendar
for events the day of Friday, October 9, 2009.

     .
events for the
events containing  

(Requires a password.)
More information on this calendar program is available.
Questions regarding events or the calendar should be directed to Tori Corkery. 
    September 2009          October 2009          November 2009    
 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  5                1  2  3    1  2  3  4  5  6  7
  6  7  8  9 10 11 12    4  5  6  7  8  9 10    8  9 10 11 12 13 14
 13 14 15 16 17 18 19   11 12 13 14 15 16 17   15 16 17 18 19 20 21
 20 21 22 23 24 25 26   18 19 20 21 22 23 24   22 23 24 25 26 27 28
 27 28 29 30            25 26 27 28 29 30 31   29 30

Friday, October 9, 2009

Women in Mathematics Seminar
1:00 pm   in 141 Altgeld Hall,  Friday, October 9, 2009
 Del 
 Edit 
 Copy 
Submitted by akwiatk2.
Alexandra Seceleanu (UIUC Math)
Weak Lefschetz Property - a computational approach
Abstract: I will begin by introducing the algebraic counterpart of the famous Lefschetz Property in differential geometry. Then we shall explore some of the tools that are available for algebraists to study the Weak Lefschetz property. I will show how to completely solve the problem in a particular case. Time permitting, I will illustrate my talk with computations using computer algebra software. This talk will be easily accessible to non-specialists.

Algebra, Geometry and Combinatorics Seminar
3:00 pm   in 445 Altgeld Hall,  Friday, October 9, 2009
 Del 
 Edit 
 Copy 
Submitted by llpku.
Patricia Hersh (North Carolina State University)
Subword complexes, 0-Hecke algebras and a map to Bruhat order
Abstract: Anders Bjorner characterized which finite, graded partially ordered sets are closure posets of regular CW complexes, and he also observed that a regular CW complex is homeomorphic to the order complex of its closure poset. One might therefore hope to use combinatorics to determine topological structure for stratified spaces such as real Schubert varieties; however, it is possible for two different CW complexes with very different topological structure to have the same closure poset. I will discuss a stratified space from total positivity theory which Sergey Fomin and Michael Shapiro conjectured to be a regular CW complex homeomorphic to a ball. I proved this conjecture using a new regularity criterion together with a map to this space from a simplex. This talk will also highlight more recent joint work with Drew Armstrong using an induced poset map from a Boolean algebra to Bruhat order to give a new proof that the proper part of Bruhat order is homotopy equivalent to a sphere.

Graduate Analysis Seminar
4:00 pm   in 341 Altgeld Hall,  Friday, October 9, 2009
 Del 
 Edit 
 Copy 
Submitted by wgreen4.
Kelly Funk (Department of Mathematics, University of Illinois)
Introduction to Nonrecurrence in Ergodic Theory
Abstract: In this talk I will discuss the issue of nonrecurrence of a sequence of natural numbers. The talk will include some basic definitions in ergodic theory, preliminary results in recurrence, and some interesting questions related to characterizing sets of nonrecurrence. This talk should be accessible to all graduate students and everyone is encouraged to attend.

Model Theory and Descriptive Set Theory
4:00 pm   in 345 Altgeld Hall,  Friday, October 9, 2009
 Del 
 Edit 
 Copy 
Submitted by w-henson.
Shichang Song (UIUC Math)
Sums and Products, VI
Abstract: This week we'll continue looking at Udi Hrushovski's paper "Stable group theory and approximate subgroups". This talk will again be introductory, with discussion of some consequences of the main theorem of the paper. In the arXiv, this is paper 0909.2190v2 [math.LO]