[HTML][HTML] Cosupports and minimal pure-injective resolutions of affine rings

T Nakamura - Journal of Algebra, 2019 - Elsevier
We prove that any affine ring R over a field k has full cosupport, ie, the cosupport of R is
equal to Spec R. Using this fact, we give a complete description of all terms in a minimal …

Cotangent spaces and separating re-embeddings

M Kreuzer, L Ngoc Long, L Robbiano - Journal of Algebra and Its …, 2022 - World Scientific
Given an affine algebra R= P/I, where P= K [x 1,…, xn] is a polynomial ring over a field K and
I is an ideal in P, we study re-embeddings of the affine scheme Spec (R), ie presentations …

Regular closure

M McDermott - Proceedings of the American Mathematical Society, 1999 - ams.org
Regular closure is an operation performed on submodules of arbitrary modules over a
commutative Noetherian ring. The regular closure contains the tight closure when both are …

An affine version of a theorem of Nagata

G Freudenburg - 2015 - projecteuclid.org
Let R be an affine k-domain over the field k. The paper's main result is that if R admits a
nontrivial embedding in a polynomial ring K [s] for some field K containing k, then R can be …

On a question of Quillen

SM Bhatwadekar, RA Rao - Transactions of the American Mathematical …, 1983 - ams.org
Let $ R $ be a regular local ring, and $ f $ a regular parameter of $ R $. Quillen asked
whether every projective ${R_f} $-module is free. We settle this question when $ R $ is a …

Free derivation modules and a criterion for regularity

S Moen - Proceedings of the American Mathematical Society, 1973 - ams.org
Let $ k $ be an algebraically closed field of characteristic zero, $ R $ an affine $ k $-algebra.
We prove that if the ideal of the variety of $ R $ can be generated by an $ S $-sequence of …

A note on 𝑝-bases of a regular affine domain extension

T Ono - Proceedings of the American Mathematical Society, 2008 - ams.org
Let $ R^ p\subseteq R'\subseteq R $ be a tower of commutative rings where $ R $ is a
regular affine domain over an algebraically closed field of prime characteristic $ p $ and …

[HTML][HTML] A finiteness property of infinite resolutions

D Eisenbud, C Huneke - Journal of Pure and Applied Algebra, 2005 - Elsevier
In this paper we prove a finiteness result for infinite minimal free resolutions over a
Noetherian local ring R: If M is a module, such as the residue field, that is locally free of …

[PDF][PDF] A resolution of the residue field over arbitrary monomial rings

H Charalambous - Journal of Algebra, 1996 - core.ac.uk
S, R s SrI. We construct a resolution of k over R. 1996 Academic Press, Inc. wx In what
follows, k is a field and S s kx,..., x is the polynomial ring 1 n in n variables over k. The …

Injective resolutions of some regular rings

K Ajitabh, SP Smith, JJ Zhang - Journal of Pure and Applied Algebra, 1999 - Elsevier
Let A be a noetherian Auslander regular ring and δ the canonical dimension function on A-
modules, which is defined as δ (M)= d− j (M) where d is the global dimension of A and j (M) …