Equigenerated Gorenstein ideals of codimension three
Abstract
We focus on the structure of a homogeneous Gorenstein ideal of codimension three in a standard polynomial ring over a field , assuming that is generated in a fixed degree . For such an ideal this degree comes along with the minimal number of generators of and the degree of the entries of the associated skew-symmetric matrix in a simple formula. We give an elementary characteristic-free argument to the effect that, for any such data linked by this formula, there exists a Gorenstein ideal of codimension three filling them. We conjecture that, for arbitrary , an ideal generated by a general set of forms of degree is Gorenstein if and only if and . We prove the `only if' implication of this conjecture when . For arbitrary , we prove that if and then the ideal is Gorenstein if and only if , which settles the `if' assertion of the conjecture for . Finally, we elaborate around one of the questions of Fr\"oberg--Lundqvist. In a different direction, we reveal a connection between the Macaulay inverse and the so-called Newton dual, a matter so far not brought out to our knowledge. Finally, we consider the question as to when the link is equigenerated, where are independent linear forms and is a form, is given a solution in some important cases.
Keywords
Cite
@article{arxiv.2005.12953,
title = {Equigenerated Gorenstein ideals of codimension three},
author = {Dayane Lira and Zaqueu Ramos and Aron Simis},
journal= {arXiv preprint arXiv:2005.12953},
year = {2021}
}