


Lecture series on algebraic stacks
Monday 20 November, 11.30 am
========================
Venue: Room No 215, Department of Mathematics
Host: Sudarshan Gurjar
Speaker: Nitin Nitsure
Affiliation: TIFR, Mumbai (Retd)
Title: The classifying stack BG for an algebraic group
Abstract: To any Lie group, there is classically associated a topological space BG with the requisite universal property in the homotopy category of paracompact topological spaces. For example, for G = GL(n) the space BG is the infinite Grassmannian. However, when we go to the algebraic category (say schemes or algebraic spaces and their morphisms), such a space BG does not exist. This is a paradigmatic example where algebraic stacks rescue the situation. In this lecture, we will explain the construction of an algebraic stack BG which has the requisite universal property of classifying principal Gbundles, where G is an algebraic group. The algebraic cohomology of this stack gives the algebraic cohomological version of the characteristic classes of principal Gbundles.
Analysis and PDE seminar
Monday 20th Nov. 4 pm  5 pm
=====================
Venue: Ramanujan Hall
Host: Sanjay Pusti
Speaker: Ankit Bhojak
Affiliation: IISER Bhopal
Title: Sharp endpoint L^pestimates for bilinear spherical maximal functions
Abstract: Attached.