TETRAHEDRAL GEOMETRY/TOPOLOGY SEMINAR

         ANNOUNCEMENT

DATE:              Friday, September 14, 2007                     

LOCATION:    Hempfield High School, Room 213 (directions at http://www.millersville.edu/~tgts/)                

                           followed by dinner at a place to be determined.

4:30 TALK:      John Carter, Franklin and Marshall College

                           “Non-loopable K-theory equivalences”

Over the summer I explored and extended a family of non-loopable K-theory equivalences

constructed by Lisa Langsetmo and Don Stanley in 2000. I will talk about why this is an

interesting family of spaces and how I extended their results.  A K-theory equivalence is a

map of spaces f : X à Y such that K(X)=K(Y).  A non-loopable equivalence is one such

that K(\Omega X) \neq K(\Omega Y).  In ordinary homology, given a homology equivalence

of 1-connected spaces, there is a homology equivalence of loop spaces.  But for K-theories

and non-connective homology theories the story is different.  There are spaces such that

K-theory can 'see' the loop space but not the space.  This is interesting not only for what it

says about what K-theory sees but also for what it says about methods for constructing loop

spaces.  (Fair warning, I will say spectral sequence a number of times during this talk.)

     EVERYONE WELCOME

       PLEASE FORWARD THIS ANNOUNCEMENT TO ANYONE INTERESTED

           The Tetrahedral Geometry/Topology Seminar is sponsored jointly by

Elizabethtown College, Franklin & Marshall College, Lebanon Valley College and Millersville University.