|DATE||May 23 (Mon), 2022|
|TITLE||Unprojections of high regularity|
|ABSTRACT||Recently, McCullough and Peeva discovered counterexamples to a conjecture of Eisenbud and Goto on the Castelnuovo-Mumford regularity. The Castelnuovo-Mumford regularity, or the regularity for short, is a very interesting invariant that measures homological and cohomological complexities of a given projective variety, and the conjecture claims that for every nondegenerate projective variety, the regularity has a certain upper bound in terms of the degree and the codimension.
In this talk, we present another way to construct counterexamples to the regularity conjecture. It is based on an unprojection process and Green’s partial elimination ideal theory.