Brandeis University Everyperson Seminar

Monday March 13, 2006, 4:00 PM

tea at 3:40 PM at the Math Department lounge (Goldsmith 300)

Speaker: Stefan Friedl

Title: The Whitney trick and why 2 ⋅ 2 ≰ 4 makes topology interesting

Abstract: The Whitney trick makes it possible to turn geometric problems into purely algebraic problems. This trick only works in dimensions greater than four. Four dimensional manifolds therefore show very different phenomena than high dimensional manifolds. I will use the problem of finding slice disks for knots to illustrate the difference between high-dimensional manifolds and four dimensional manifolds.