• Title/Summary/Keyword: Dedekind modules

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On Strongly Extending Modules

  • Atani, S. Ebrahimi;Khoramdel, M.;Hesari, S. Dolati Pish
    • Kyungpook Mathematical Journal
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    • v.54 no.2
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    • pp.237-247
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    • 2014
  • The purpose of this paper is to introduce the concept of strongly extending modules which are particular subclass of the class of extending modules, and study some basic properties of this new class of modules. A module M is called strongly extending if each submodule of M is essential in a fully invariant direct summand of M. In this paper we examine the behavior of the class of strongly extending modules with respect to the preservation of this property in direct summands and direct sums and give some properties of these modules, for instance, strongly summand intersection property and weakly co-Hopfian property. Also such modules are characterized over commutative Dedekind domains.

ON STRONGLY GORENSTEIN HEREDITARY RINGS

  • Hu, Kui;Kim, Hwankoo;Wang, Fanggui;Xu, Longyu;Zhou, Dechuan
    • Bulletin of the Korean Mathematical Society
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    • v.56 no.2
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    • pp.373-382
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    • 2019
  • In this note, we mainly discuss strongly Gorenstein hereditary rings. We prove that for any ring, the class of SG-projective modules and the class of G-projective modules coincide if and only if the class of SG-projective modules is closed under extension. From this we get that a ring is an SG-hereditary ring if and only if every ideal is G-projective and the class of SG-projective modules is closed under extension. We also give some examples of domains whose ideals are SG-projective.

CATENARY MODULES II

  • NAMAZI, S.;SHARIF, H.
    • Honam Mathematical Journal
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    • v.22 no.1
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    • pp.9-16
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    • 2000
  • An A-module M is catenary if for each pair of prime submodules K and L of M with $K{\subset}L$ all saturated chains of prime submodules of M from K to L have a common finite length. We show that when A is a Noetherian domain, then every finitely generated A-module is catenary if and only if A is a Dedekind domain or a field. Moreover, a torsion-free divisible A-module M is catenary if and only if the vector space M over Q(A) (the field of fractions of A) is finite dimensional.

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THE OHM-RUSH CONTENT FUNCTION III: COMPLETION, GLOBALIZATION, AND POWER-CONTENT ALGEBRAS

  • Epstein, Neil;Shapiro, Jay
    • Journal of the Korean Mathematical Society
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    • v.58 no.6
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    • pp.1311-1325
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    • 2021
  • One says that a ring homomorphism R → S is Ohm-Rush if extension commutes with arbitrary intersection of ideals, or equivalently if for any element f ∈ S, there is a unique smallest ideal of R whose extension to S contains f, called the content of f. For Noetherian local rings, we analyze whether the completion map is Ohm-Rush. We show that the answer is typically 'yes' in dimension one, but 'no' in higher dimension, and in any case it coincides with the content map having good algebraic properties. We then analyze the question of when the Ohm-Rush property globalizes in faithfully flat modules and algebras over a 1-dimensional Noetherian domain, culminating both in a positive result and a counterexample. Finally, we introduce a notion that we show is strictly between the Ohm-Rush property and the weak content algebra property.