Seminar series
Date
Mon, 26 Jan 2026
16:00
16:00
Location
C5
Speaker
Suvir Rathore
Organisation
Cambridge University
Abstract: In number theory, one often studies compatible systems of l-adic representations of geometric origin where l is a prime number. The proof of the Weil conjectures (in particular the Riemann hypothesis) show the the l-adic cohomology of a variety over a finite field is independent of l in some sense.
After proving the Weil conjectures, Deligne offered some more general conjectures, which hint at deeper l-independence statements as predicted by Grothendieck's vision of a theory of motives. One key input in proving this conjecture is the Langland's correspondence.
We will introduce this phenomenon guided by the conjectural theory of motives through the lens of a universal cohomology theory, and explain how one uses the Langlands correspondence.