Corrigendum: Generalizations of graded Clifford algebras and of complete intersections

Abstract

A correction is provided for Proposition 3.5 in the above‐mentioned article. The correction is: if S is a skew polynomial ring on finitely many generators of degree 1 that are normal elements in S, and if I is a homogeneous ideal of S that is generated by a normalizing sequence, then prefixdimdouble-struckkfalse(S/Ifalse) is finite if and only if S/I has no point modules and no fat point modules. A similar correction is provided for Corollary 3.6 of the same article.

Cocycle twists of algebras

“…. , n, and satisfies one of the equivalent conditions of [17,Corollary 11]. Then the main theorem states that A(µ, M 1 , .…”

“…cit., which is correct as stated under the changes in the relevant definitions given by [17,Definition 2]. It relates to a condition on the quadric system determined by q k = zM k z T for k = 1, .…”

“…There is a recent corrigendum to [18], namely [17], which contains modifications of several definitions and results. Where appropriate we will reference the corrigendum;…”