ALMOST PERFECT LOCAL DOMAINS AND THEIR DOMINATING ARCHIMEDEAN VALUATION DOMAINS

2002 ◽  
Vol 01 (04) ◽  
pp. 451-467 ◽  
Author(s):  
PAOLO ZANARDO
Keyword(s):  
Commutative Ring ◽  
Maximal Ideal ◽  
Integral Closure ◽  
Nonzero Ideal ◽  
Valuation Domain ◽  
Local Domain ◽  
Valuation Domains ◽  
Domain V

A commutative ring R is said to be almost perfect if R/I is perfect for every nonzero ideal I of R. We prove that an almost perfect local domain R is dominated by a unique archimedean valuation domain V of its field of quotients Q if and only if the integral closure of R contains an ideal of V. We show how to construct almost perfect local domains dominated by finitely many archimedean valuation domains. We provide several examples illustrating various possible situations. In particular, we construct an almost perfect local domain whose maximal ideal is not almost nilpotent.

Condensed Domains

2003 ◽  
Vol 46 (1) ◽  
pp. 3-13 ◽  
Author(s):  
D. D. Anderson ◽  
Tiberiu Dumitrescu
Keyword(s):  
Maximal Ideal ◽  
Integral Domain ◽  
Field Extension ◽  
Integral Closure ◽  
Dedekind Domain ◽  
Closed Domain ◽  
Local Domain ◽  
Noetherian Domain ◽  
Integrally Closed ◽  
Finite Integral

AbstractAn integral domain D with identity is condensed (resp., strongly condensed) if for each pair of ideals I, J of D, IJ = {ij ; i ∈ I; j ∈ J} (resp., IJ = iJ for some i ∈ I or IJ = Ij for some j ∈ J). We show that for a Noetherian domain D, D is condensed if and only if Pic(D) = 0 and D is locally condensed, while a local domain is strongly condensed if and only if it has the two-generator property. An integrally closed domain D is strongly condensed if and only if D is a Bézout generalized Dedekind domain with at most one maximal ideal of height greater than one. We give a number of equivalencies for a local domain with finite integral closure to be strongly condensed. Finally, we show that for a field extension k ⊆ K, the domain D = k + XK[[X]] is condensed if and only if [K : k] ≤ 2 or [K : k] = 3 and each degree-two polynomial in k[X] splits over k, while D is strongly condensed if and only if [K : k] ≤ 2.

ALGEBRAIC ENTROPY OF ENDOMORPHISMS OVER LOCAL ONE-DIMENSIONAL DOMAINS

2009 ◽  
Vol 08 (06) ◽  
pp. 759-777 ◽  
Author(s):  
PAOLO ZANARDO
Keyword(s):  
Maximal Ideal ◽  
Residue Field ◽  
Field Extension ◽  
Valuation Domain ◽  
One Dimensional ◽  
Natural Properties ◽  
Algebraic Entropy ◽  
Number Of Generators ◽  
Domain V ◽  
Dimensional Integral

Let R be a local one-dimensional integral domain, with maximal ideal 𝔐 and field of fractions Q. Here, a local ring is not necessarily Noetherian. We consider the algebraic entropy ent g, defined using the invariant gen, where, for M a finitely generated R-module, gen (M) is its minimal number of generators. We relate some natural properties of R with the algebraic entropies ent g(ϕ) of the elements ϕ ∈ Q, regarded as endomorphisms in End R(Q). Specifically, let R be dominated by an Archimedean valuation domain V, with maximal ideal P. We examine the uniqueness of V, the transcendency of the residue field extension V/P over R/𝔐, and the condition for R to be a pseudo-valuation domain. We get mutual information between these properties and the behavior of ent g, focusing on the conditions ent g(ϕ) = 0 for every ϕ ∈ Q, ent g(ψ) = ∞ for some ψ ∈ Q, and ent g(ϕ) < ∞ for every ϕ ∈ Q.

GENERALLY t-LINKATIVE DOMAINS

2012 ◽  
Vol 11 (02) ◽  
pp. 1250027
Author(s):  
THOMAS G. LUCAS
Keyword(s):  
Finite Type ◽  
Maximal Ideal ◽  
Integral Domain ◽  
Type System ◽  
Nonzero Ideal ◽  
Two Dimensional ◽  
Finitely Generated ◽  
One Dimensional ◽  
Valuation Domains ◽  
Prüfer Domains

An overring t of an integral domain R is t-linked over R if for each finitely generated nonzero ideal I of R, (T : IT) ⊋ T implies (R : I) ⊋ R. A t-linkative domain is one for which each overring is t-linked. The notion of a generally t-linkative domain is introduced as a domain R such that [Formula: see text] is t-linkative for each finite type system of ideals [Formula: see text]. In general, R is generally t-linkative if and only if RM is generally t-linkative for each maximal ideal M. All Prüfer domains are generally t-linkative as are all one-dimensional domains and all pseudo-valuation domains. If R is Noetherian and not a field, then it is generally t-linkative if and only if it is one-dimensional. In contrast, an example is given of a two-dimensional Mori domain that is generally t-linkative.

A note on valuations associated with a local domain

1955 ◽  
Vol 51 (2) ◽  
pp. 252-253 ◽  
Author(s):  
D. Rees
Keyword(s):  
Maximal Ideal ◽  
Present Note ◽  
Integral Closure ◽  
Local Domain ◽  
Valuation Rings ◽  
Integrally Closed ◽  
Primary Ideals

The purpose of the present note is to prove the following two theorems:Theorem 1. Let Q be an equicharacteristic local domain with maximal ideal m. Let a be any ideal of Q. Then the intersection of all integrally closed m-primary ideals of Q which contain a is the integral closure ā of a.Theorem 2. If Q is as above, and if S denotes the set of valuations on the field of fractions F of Q which are associated with Q, then the intersection of the valuation rings belonging to valuations in S is the integral closure of Q.

Generators of Orthogonal Groups over Valuation Rings

1981 ◽  
Vol 33 (1) ◽  
pp. 116-128 ◽  
Author(s):  
Hiroyuki Ishibashi
Keyword(s):  
Commutative Ring ◽  
Local Ring ◽  
Maximal Ideal ◽  
Orthogonal Group ◽  
Valuation Ring ◽  
Unit Element ◽  
Orthogonal Groups ◽  
Valuation Rings ◽  
Number Of Factors ◽  
Valuation Domains

Let be a valuation ring with unit element, i.e., is a commutative ring such that for any a and b in , either a divides b or b divides a. We assume 2 is a unit of . V is an n-ary nonsingular quadratic module over , O(V) or On(V) is the orthogonal group on V, and S is the set of symmetries in O(V). We define l(σ) to be the minimal number of factors in the expression of a of O(V) as a product of symmetries on V. For the case where is a field, l(σ) has been determined by P. Scherk [6] and J. Dieudonné [1]. In [3] I have generalized the results of Scherk to orthogonal groups over valuation domains. In the present paper I generalize my results of [3] to orthogonal groups over valuation rings.Since is a valuation ring, it is a local ring with the maximal ideal A which consists of all nonunits of .

2-Visible Submodules and Fully 2-Visible Modules

2019 ◽  
pp. 1-6
Author(s):  
Mahmood S. Fiadh ◽  
Wafaa H. Hanoon
Keyword(s):  
Commutative Ring ◽  
Nonzero Ideal ◽  
The Relationship

Let be a -module, T is a commutative ring with identity and be a proper submodule of . In this paper we introduce the concepts of 2-visible submodules and fully 2-visible modules as a generalizations of visible submodules and fully visible modules resp., where is said to be 2-visible whenever for every nonzero ideal of and A -module is called fully 2-visible if for any proper submodule of it is 2-visible.Study some of the properties of these concepts also discuss the relationship 2-visible submodules and fully 2-visible modules with 2-pure submoules and other related submodules and modules resp. are given.

scholarly journals On complete integral closure and Archimedean valuation domains

1996 ◽  
Vol 61 (3) ◽  
pp. 377-380 ◽  
Author(s):  
Robert Gilmer
Keyword(s):  
Integral Domain ◽  
Integral Closure ◽  
Extension Field ◽  
Quotient Field ◽  
Valuation Domains ◽  
Complete Integral Closure

AbstractSuppose D is an integral domain with quotient field K and that L is an extension field of K. We show in Theorem 4 that if the complete integral closure of D is an intersection of Archimedean valuation domains on K, then the complete integral closure of D in L is an intersection of Archimedean valuation domains on L; this answers a question raised by Gilmer and Heinzer in 1965.

Ordinary Singularities with Decreasing Hilbert Function

1982 ◽  
Vol 34 (1) ◽  
pp. 169-180 ◽  
Author(s):  
Leslie G. Roberts
Keyword(s):  
Maximal Ideal ◽  
Integral Domain ◽  
Hilbert Function ◽  
Integral Closure ◽  
Minimal Prime Ideal ◽  
Quotient Field ◽  
Graded Ring ◽  
Image Position ◽  
Minimal Prime ◽  
Dimension One

Let A be the co-ordinate ring of a reduced curve over a field k. This means that A is an algebra of finite type over k, A has no nilpotent elements, and that if P is a minimal prime ideal of A, then A/P is an integral domain of Krull dimension one. Let M be a maximal ideal of A. Then G(A) (the graded ring of A relative to M) is defined to be . We get the same graded ring if we first localize at M, and then form the graded ring of AM relative to the maximal ideal MAM. That isLet Ā be the integral closure of A. If P1, P2, …, Ps are the minimal primes of A thenwhere A/Pi is a domain and is the integral closure of A/Pi in its quotient field.

Generators of Un(V) Over a Quasi Semilocal Semihereditary Ring

1981 ◽  
Vol 33 (5) ◽  
pp. 1232-1244 ◽  
Author(s):  
Hiroyuki Ishibashi
Keyword(s):  
Commutative Ring ◽  
Maximal Ideal ◽  
Valuation Ring ◽  
Hermitian Form ◽  
Free Module ◽  
Fixed Element ◽  
Semihereditary Ring ◽  
Maximal Ideals ◽  
Sesquilinear Form

Let o be a quasi semilocal semihereditary ring, i.e., o is a commutative ring with 1 which has finitely many maximal ideals {Ai|i ∊ I} and the localization oAi at any maximal ideal Ai is a valuation ring. We assume 2 is a unit in o. Furthermore * denotes an involution on o with the property that there exists a unit θ in o such that θ* = –θ. V is an n-ary free module over o with f : V × V → o a λ-Hermitian form. Thus λ is a fixed element of o with λλ* = 1 and f is a sesquilinear form satisfying f(x, y)* = λf(y, x) for all x, y in V. Assume the form is nonsingular; that is, the mapping M → Hom (M, A) given by x → f( , x) is an isomorphism. In this paper we shall write f(x, y) = xy for x, y in V.

Sign in / Sign up

Export Citation Format

Share Document