Department of

# Mathematics

Seminar Calendar
for events the day of Friday, February 28, 2014.

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events for the
events containing

Questions regarding events or the calendar should be directed to Tori Corkery.
     January 2014          February 2014            March 2014
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                      1
5  6  7  8  9 10 11    2  3  4  5  6  7  8    2  3  4  5  6  7  8
12 13 14 15 16 17 18    9 10 11 12 13 14 15    9 10 11 12 13 14 15
19 20 21 22 23 24 25   16 17 18 19 20 21 22   16 17 18 19 20 21 22
26 27 28 29 30 31      23 24 25 26 27 28      23 24 25 26 27 28 29
30 31


Friday, February 28, 2014

3:00 pm in 343 Altgeld Hall,Friday, February 28, 2014

#### 0-Hecke algebra actions on coinvariants, flags, and Stanley-Reisner rings

###### Jia Huang (U. Minnesota)

Abstract: The 0-Hecke algebra is a deformation of the group algebra of the symmetric group. In this talk I will first review some interesting results regarding the symmetric group actions on coinvariants, finite flags, and Stanley-Reisner rings, and then present analogous results that I obtained for the 0-Hecke algebra actions on these objects.

4:00 pm in 243 Altgeld Hall,Friday, February 28, 2014

#### There is life on L^p: Examples of operator algebras on L^p spaces

###### Chris Phillips (University of Oregon)

Abstract: Banach space theorists will certainly tell you many interesting things about L^p spaces ("there is life _in_ L^p"). We exhibit what we believe to be interesting examples of operator algebras _on_ L^p spaces. We will concentrate on L^p analogs of Cuntz algebras and UHF algebras. (There is also work on reduced group L^p operator algebras, crossed products, and L^p analogs of irrational rotation algebras.) The basic properties of the C*-algebras carry over: for the L^p analogs of Cuntz algebras, simplicity, uniqueness, pure infiniteness, amenability, and the K-theory; for the L^p analogs of UHF algebras, simplicity, unique tracial state, and, for fixed p, classification in terms of K-theory. Sometimes the proofs are harder; occasionally, they are completely different (and do not work for p = 2). There are also new phemonena: none of these algebras for one value of p can ever be isomorphic to any such algebra for any other value of p.

4:00 pm in 241 Altgeld Hall,Friday, February 28, 2014

#### Automorphisms of free groups and Outer Space

###### Caglar Uyanik (UIUC Math)

Abstract: The study of outer automorphism group of a free group $F_N$ has greatly benefited from its analogy with the mapping class group. In this talk we will talk about the analogs of the Teichmuller space of a surface in the free group setting and show how one can retract information about the individual elements in $Out(F_N)$ by analyzing their action on various spaces. In particular, we will define Outer Space and space of geodesic currents and show some pictures.

4:00 pm in 345 Altgeld Hall,Friday, February 28, 2014

#### Measuring definable sets in o-minimal fields

###### Jana Marikova (Western Illinois)

Abstract: Let R be an o-minimal field. We propose a measure on the R-definable sets contained in the finite part of R^n. While this measure is not real-valued, it does take values in an ordered semiring and has various desirable properties, such as assigning a positive value to precisely the measurable sets with non-empty interior and satisfying a change of variables formula. This is joint work with Masahiro Shiota.