Subresultants and the Shape Lemma

Abstract

In nice cases, a zero-dimensional complete intersection ideal over a field of characteristic zero has a Shape Lemma. There are also cases where the ideal is generated by the resultant and first subresultant polynomials of the generators. This paper explores the relation between these representations and studies when the resultant generates the elimination ideal. We also prove a Poisson formula for resultants arising from the hidden variable method.

25 pages, revised version with several changes in sections 2, 3, and 5. Accepted for publication at Mathematics of Computation