Seminar Calendar
for events the day of Wednesday, March 16, 2011.

.
events for the
events containing

Questions regarding events or the calendar should be directed to Tori Corkery.
    February 2011            March 2011             April 2011
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  4  5                   1  2
6  7  8  9 10 11 12    6  7  8  9 10 11 12    3  4  5  6  7  8  9
13 14 15 16 17 18 19   13 14 15 16 17 18 19   10 11 12 13 14 15 16
20 21 22 23 24 25 26   20 21 22 23 24 25 26   17 18 19 20 21 22 23
27 28                  27 28 29 30 31         24 25 26 27 28 29 30



Wednesday, March 16, 2011

Algebra, Geometry and Combinatorics Seminar
3:00 pm   in 7 Illini Hall,  Wednesday, March 16, 2011
 Del Edit Copy
Submitted by ecsima.
 Hamid Kulosman (University of Louisville)Zero-divisor graphs of some special semigroupsAbstract: We introduce the notion of special semigroups. They are commutative Boolean semigroups that can be built from a trivial semigroup in finitely many steps, where in each step an idempotent is adjoined in one of the three allowed ways. The $i$-th step of the building process is completely described by an element $a_i$ of the set $\{\mathrm{'id'}, \mathrm{'ze'}, 0,1,\dots, i-1 \}$ of $i+2$ elements. The sequence $\mathbf{a}=a_0, a_1,\dots, a_N$, obtained in that way, is called a defining sequence of the semigroup. It follows that the special semigroups form a large class of semigroups each of which can be easily defined. They can be arbitrarily big, nevertheless checking of associativity is completely avoided. Because of that they can be useful for various purposes. We give the description of the zero-divisor graphs of special semigroups and prove various properties of them. This is a joint work with Alica Miller.

Math 499: Introduction to Graduate Mathematics
4:00 pm   in 245 Altgeld Hall,  Wednesday, March 16, 2011
 Del Edit Copy
Submitted by seminar.
 Charles Rezk (Department of Mathematics, University of Illinois)Arithmetic of vector spacesAbstract: Just as you can add and multiply integers, you can add and multiply (and even subtract!) vector spaces (or representations, or vector bundles ...). I'll describe how this idea leads to the notion of K-theory. Then I'll describe some new kinds of "arithmetic operations" for such things, beyond the familiar ones you find on a calculator.