Joshua Ciappara will give the Seminar’s eighth talk in Semester 2 tomorrow 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: Euler and Pontryagin classes Abstract: We will begin with a reminder on Grassmannians and universal bundles, and particularly their connection to characteristic classes. This background will motivate the goal of calculating the integral cohomology rings of the classifying space G_n and its counterpart for oriented vector bundles. On the road to the answer, we will introduce Euler and Pontryagin classes and explore their basic properties (including the reason Euler classes are so named). Time and date: 3 pm Wednesday 28 October Seminar website: https://www.maths.usyd.edu.au/u/ciappara/SAS.html