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-2 votes
2 answers
764 views

Reduced ring with all non-prime ideals finitely generated

Let $R$ be a reduced ring with all non-prime ideals finitely generated. Then is $R$ Noetherian ? If not, then is it true at least in the local case ? Without reduced assumption, it is not true even ...
user avatar
9 votes
1 answer
444 views

Rings with all non-prime ideals finitely generated

Motivated by this question, I would like to ask: If all non-prime ideals in a ring are finitely generated, then is the ring Noetherian? Can we at least say anything in the local case? Note that ...
user avatar
5 votes
1 answer
1k views

local ring all whose non-maximal ideals are finitely generated

Let $(R, \mathfrak m)$ be a commutative local ring such that every non-maximal ideal is finitely generated. Then, is $R$ Noetherian i.e. is $\mathfrak m$ finitely generated ideal ? It is easy to see ...
user avatar
4 votes
0 answers
177 views

What kind of module is this?

Recall that, if $R$ is a commutative ring, then a suitably finite $R$-module $M$ is projective if and only if the localization $M_\mathfrak{m}$ is a direct sum of finitely many copies of $R_\mathfrak{...
Ben Knudsen's user avatar
7 votes
1 answer
1k views

indecomposable module over a local ring

I ask this in mathematics for some days.it doesn't have an answer up to now. https://math.stackexchange.com/questions/2565828/indecomposable-module-over-a-local-ring As we all know, for an arbitrary ...
Jian's user avatar
  • 496
9 votes
2 answers
713 views

The projective covers of Artinian module

The injective hull for a module always exists, however over certain rings modules may not have projective covers. I have a question. If $A$ is an Artinian module on a Noetherian local ring $R$ then $...
Tran Duc Dung's user avatar
1 vote
0 answers
294 views

Is it true that the functor of completion of a module over a local ring is injective on isomorphism classes?

Let $A$ be a commutative Noetherian local ring and $\hat A$ be its completion. Then we have the functor of completion from the category of finitely generated $A$-modules to the category of finitely ...
Sergei Ivanov's user avatar
2 votes
1 answer
227 views

when there is an injection $0 \to R \to K_R$?

Let $(R,m)$ be a Cohen-Macaulay local ring which possesses the canonical module $K_R$. Then $R$ is said to be an almost Gorenstein local ring, if there is an exact sequence $0 \to R \to K_R \to C \to ...
user 1's user avatar
  • 1,355
7 votes
2 answers
736 views

invariants that can be measured by Local Cohomology

What invariants can be measured by Local Cohomology (and what application it has)? As an example of what I mean: Local Cohomology can measure invariants like depth and dim. So in some cases Local ...
user 1's user avatar
  • 1,355
2 votes
1 answer
191 views

what are the possible approximations for ideals

(Fix some local ring $(R,\mathfrak{m})$ over a field of zero characteristic.) Suppose an ideal $J$ is defined by some complicated formula/procedure. And there is no hope of computing it/or writing ...
Dmitry Kerner's user avatar
4 votes
2 answers
414 views

Maximal Cohen-Macaulay modules of type one

Does anybody know an example of a Noetherian local ring $(R,m)$ which admits a maximal Cohen-Macaulay module of type one, but the ring $R$ itself is not CM? If $C$ is a maximal CM module then the ...
S.Hamid  Hassanzadeh's user avatar
2 votes
1 answer
169 views

Open idempotents in modules over a local ring

Let $R$ be a local ring. By an open idempotent I mean an $R$-module $F$ equipped with a homomorphism $e : F \to R$ such that $e \otimes F = F \otimes e$ is an isomorphism $F \otimes F \cong F$ (this ...
Martin Brandenburg's user avatar
1 vote
2 answers
552 views

A Question About Free Resolutions

I would warmly appreciate it if someone could tell me whether the following question has an affirmative answer. I am new to the field of commutative algebra, so I am simply trying to fill in some (...
Leonard's user avatar
  • 816
3 votes
1 answer
879 views

Minimal generating set of a free module over local ring

Greetings, in my studies I went into a statement "minimal generating set of a free module over a local ring is a free basis". The statement came without a proof, just with a reference to Kaplansky's ...
Ivo Jan's user avatar
  • 33
3 votes
4 answers
3k views

When a group ring is a local ring [closed]

Hi there, I'm stuck with my undergraduate thesis on the following proposition: If $k$ is a field of characteristic $p > 0$ and $G$ is a finite $p$-group, then the group ring $kG$ is local. In ...
Marco Larrea's user avatar