# Colloquium abstracts

**Jyoti Singh**

MNNIT, Allahabad

October 16, 2014

**An algebraic proof of the Involutivity theorem**: An important geometric invariant in the theory of $D$-modules is the characteristic variety and its involutivity is a vital result in this theory. In this talk, we discuss an algebraic proof of the involutivity theorem which says that the characteristic ideal of a module is closed under a Poisson bracket.