Mathematics – Commutative Algebra
Scientific paper
2011-03-24
Mathematics
Commutative Algebra
19 pages
Scientific paper
Let $R$ be a commutative Noetherian ring. We give criteria for flatness of $R$-modules in terms of associated primes and torsion-freeness of certain tensor products. This allows us to develop a criterion for regularity if $R$ has characteristic $p$, or more generally if it has a locally contracting endomorphism. Dualizing, we give criteria for injectivity of $R$-modules in terms of coassociated primes and (h-)divisibility of certain $\Hom$-modules. Along the way, we develop tools to achieve such a dual result. These include a careful analysis of the notions of divisibility and h-divisibility (including a localization result), a theorem on coassociated primes across a $\Hom$-module base change, and a local criterion for injectivity.
Epstein Neil
Yao Yongwei
No associations
LandOfFree
Criteria for flatness and injectivity does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Criteria for flatness and injectivity, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Criteria for flatness and injectivity will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-47488