Student Algebra Seminar: Hone -- Characteristic classes as obstructions

Christopher Hone will give the Seminar’s ninth talk in Semester 2 this Thursday
afternoon on Zoom.  Please find the details below.  Anyone desiring to attend the talk
or join the mailing list is warmly invited to get in touch: ciappara@maths.usyd.edu.au.  

Title: Characteristic classes as obstructions

Abstract: We will start with a short review of homotopy theory, in particular how maps
between CW complexes are determined by maps between homotopy groups.  In general, this
data is completely unmanageable, but in the special case of sections of fibres bundles,
it can simplify to cohomological data, giving well defined "obstructions" to
constructing sections of bundles.  For appropriate fibre bundles, we will see how this
interpretation gives rise to Stiefel--Whitney classes of vector bundles, and the Euler
class.  

Time and date: 4 pm Thursday 5 November 

Seminar website: https://www.maths.usyd.edu.au/u/ciappara/SAS.html