6 papers
The linkage class of a grade three complete intersection
Lorenzo Guerrieri, Xianglong Ni, Jerzy Weyman
Working over a field of characteristic zero, we give structure theorems for all grade three licci ideals and their minimal free resolutions. In particular, we completely classify s…
Powers of binary forms and derived Hermite reciprocity
Claudiu Raicu, Steven V Sam, Jerzy Weyman +1
For , Hilbert found in 1886 a collection of polynomial equations that cut out set-theoretically the variety X parametrizing a-th powers of binary forms of degree b. We d…
Grade three perfect ideals and length four self-dual resolutions
Lorenzo Guerrieri, Tymoteusz Chmiel, Xianglong Ni +1
Starting with a grade three perfect ideal , we demonstrate how to produce the a self-dual resolution of length four using the resolution of the original ideal. This pr…
Generic models of licci ideals parametrized by Schur functors
Lorenzo Guerrieri, Xianglong Ni, Jerzy Weyman
Let R be a commutative Noetherian ring. Licci ideals are the ideals of R that can be linked in a finite number of steps to a complete intersection. Each licci ideal admits a rigid…
Structure theorems for Gorenstein ideals of codimension four with small number of generators
Tymoteusz Chmiel, Lorenzo Guerrieri, Xianglong Ni +1
In this article we study minimal free resolutions of Gorenstein ideals of codimension four, using methods coming from representation theory. We introduce families of higher structu…
Residual Intersections and Schubert Varieties
Sara Angela Filippini, Xianglong Ni, Jacinta Torres +1
Inspired by the work of Ulrich and Huneke-Ulrich, we describe a pattern to show that the ideals of certain opposite embedded Schubert varieties defined by this pattern arise by tak…