scholarly journals On elemental annihilator rings

1970 ◽  
Vol 17 (2) ◽  
pp. 187-188 ◽  
Author(s):  
R. Yue Chi Ming
Keyword(s):  
Left Ideal ◽  
Artinian Ring ◽  
Unitary Module ◽  
Left Annihilator

Throughout this note A denotes a ring with identity, and “ module ” means “ left unitary module ”. In (2), C. Yohe studied elemental annihilator rings (e.a.r. for brevity). An e.a.r. is defined as a ring in which every ideal is the annihilator of an element of the ring. For example, a semi-simple, Artinian ring is an e.a.r. A is a l.e.a.r. (left elemental annihilator ring) if every left ideal is the left annihilator of an element of the ring. A r.e.a.r. (right elemental annihilator ring) is denned similarly.

scholarly journals A note on extensions of Baer and P. P. -rings

1974 ◽  
Vol 18 (4) ◽  
pp. 470-473 ◽  
Author(s):  
Efraim P. Armendariz
Keyword(s):  
Left Ideal ◽  
Polynomial Identity ◽  
Polynomial Rings ◽  
Nilpotent Elements ◽  
Baer Ring ◽  
Baer Rings ◽  
Left Annihilator

Baer rings are rings in which the left (right) annihilator of each subset is generated by an idempotent [6]. Closely related to Baer rings are left P.P.-rings; these are rings in which each principal left ideal is projective, or equivalently, rings in which the left annihilator of each element is generated by an idempotent. Both Baer and P.P.-rings have been extensively studied (e.g. [2], [1], [3], [7]) and it is known that both of these properties are not stable relative to the formation of polynomial rings [5]. However we will show that if a ring R has no nonzero nilpotent elements then R[X] is a Baer or P.P.-ring if and only if R is a Baer or P.P.-ring. This generalizes a result of S. Jøndrup [5] who proved stability for commutative P.P.-rings via localizations – a technique which is, of course, not available to us. We also consider the converse to the well-known result that the center of a Baer ring is a Baer ring [6] and show that if R has no nonzero nilpotent elements, satisfies a polynomial identity and has a Baer ring as center, then R must be a Baer ring. We include examples to illustrate that all the hypotheses are needed.

scholarly journals Decreasing Baer semigroups

1969 ◽  
Vol 10 (1) ◽  
pp. 46-51 ◽  
Author(s):  
M. F. Janowitz
Keyword(s):  
Left Ideal ◽  
Lattice Theory ◽  
Multiplicative Semigroup ◽  
Partially Order ◽  
Set Inclusion ◽  
Left Annihilator

In [8] and [9] we initiated a study of lattice theory by means of Baer semigroups. Basically, a Baer semigroup is a multiplicative semigroup with 0 in which the left annihilator L(x) of each element x is a principal left ideal generated by an idempotent, while its right annihilator R(x) is a principal right ideal generated by an idempotent. By [8, Lemma 2, p. 86], L(0) has a unique idempotent generator 1 which is effective as a two-sided multiplicative identity for S. For any Baer semigroup S, if we use set inclusion to partially order both ℒ = ℒ (S) = {L(x) | x ∈ S} and ℛ = ℛ (S) = {R(x) | x ∈ S}, we have by [8, Theorem 5, p. 86], that ℒ and ℛ form dual isomorphic lattices with 0 and 1. The Baer semigroup S is said to coordinatize the lattice L in case ℒ(S) is isomorphic to L. In connection with this, it is important to note that by [9, Theorem 2.3, p. 1214], a poset P with 0 and 1 is a lattice if and only if it can be coordinatized by a Baer semigroup.

BAER ENDOMORPHISM RINGS AND ENVELOPES

2010 ◽  
Vol 09 (03) ◽  
pp. 365-381 ◽  
Author(s):  
LIXIN MAO
Keyword(s):  
Direct Summand ◽  
Left Ideal ◽  
Nonempty Subset ◽  
Finitely Generated ◽  
Endomorphism Rings ◽  
Baer Ring ◽  
Baer Rings ◽  
Left Annihilator

R is called a Baer ring if the left annihilator of every nonempty subset of R is a direct summand of RR. R is said to be a left AFG ring in case the left annihilator of every nonempty subset of R is a finitely generated left ideal. In this paper, we study Baer rings and AFG rings of endomorphisms of modules in terms of envelopes. Some known results are extended.

Modules Whose Endomorphism Rings Are (m, n)-Coherent

2019 ◽  
Vol 26 (02) ◽  
pp. 231-242
Author(s):  
Xiaoqiang Luo ◽  
Lixin Mao
Keyword(s):  
Left Ideal ◽  
Endomorphism Ring ◽  
Finitely Generated ◽  
Endomorphism Rings ◽  
Von Neumann ◽  
Von Neumann Regular ◽  
Coherent Ring ◽  
Left Annihilator

Let M be a right R-module with endomorphism ring S. We study the left (m, n)-coherence of S. It is shown that S is a left (m, n)-coherent ring if and only if the left annihilator [Formula: see text] is a finitely generated left ideal of Mn(S) for any M-m-generated submodule X of Mn if and only if every M-(n, m)-presented right R-module has an add M-preenvelope. As a consequence, we investigate when the endomorphism ring S is left coherent, left pseudo-coherent, left semihereditary or von Neumann regular.

Principally quasi-Baer properties of group rings

2012 ◽  
Vol 49 (4) ◽  
pp. 454-465
Author(s):  
Libo Zan ◽  
Jianlong Chen
Keyword(s):  
Finite Group ◽  
Left Ideal ◽  
Group Ring ◽  
Group Rings ◽  
A Finite Group ◽  
Left Annihilator

A ring R is called left p.q.-Baer if the left annihilator of a principal left ideal is generated, as a left ideal, by an idempotent. It is first proved that for a ring R and a group G, if the group ring RG is left p.q.-Baer then so is R; if in condition G is finite then |G|−1 ∈ R. Counterexamples are given to answer the question whether the group ring RG is left p.q.-Baer if R is left p.q.-Baer and G is a finite group with |G|−1 ∈ R. Further, RD∞ is left p.q.-Baer if and only if R is left p.q.-Baer.

scholarly journals On Maximal Rings of Right Quotients

1962 ◽  
Vol 5 (2) ◽  
pp. 147-149 ◽  
Author(s):  
Joanne Christensen
Keyword(s):  
Left Ideal ◽  
Endomorphism Rings ◽  
Division Rings ◽  
Left Annihilator

Utumi has shown [3, Claim 5.1] that for a certain class of rings the associated maximal rings of right quotients are isomorphic to the endomorphism rings of modules over division rings. We shall prove a generalization of this theorem and then show how it is obtained as a corollary. The following proofs do not depend on Utumi's paper; instead, they make extensive use of results proved in [1]. The terminology and notations employed here are the same as in [1].I wish to thank Dr. B. Banaschewski for his suggestions and helpful criticism.LEMMA: If J is a left ideal with zero left annihilator in a ring R then a maximal ring of right quotients of R is also a maximal ring of right quotients of J.

FACTOR RINGS OF PSEUDO-FROBENIUS RINGS

2006 ◽  
Vol 05 (06) ◽  
pp. 847-854 ◽  
Author(s):  
CARL FAITH
Keyword(s):  
Left Ideal ◽  
Single Element ◽  
Local Rings ◽  
Central Idempotent ◽  
Main Result Theorem ◽  
Matrix Rings ◽  
Frobenius Rings ◽  
Result Theorem ◽  
Finite Products ◽  
Left Annihilator

If R is right pseudo-Frobenius (= PF), and A is an ideal, when is R/A right PF? Our main result, Theorem 3.7, states that this happens iff the ideal A′ of the basic ring B of R corresponding to A has left annihilator F in B generated by a single element on both sides. Moreover, in this case B/A′ ≈ F in mod-B, (see Theorem 3.5), a property that does not extend to R, that is, in general R/A is not isomorphic to the left annihilator of A. (See Example 4.3(2) and Theorem 4.5.) Theorem 4.6 characterizes Frobenius rings among quasi-Frobenius (QF) rings. As an application of the main theorem, in Theorem 3.9 we prove that if A is generated as a right or left ideal by an idempotent e, then e is central (and R/A is then trivially right PF along with R). This generalizes the result of F. W. Anderson for quasi-Frobenius rings. (See Theorem 2.2 for a new proof.). In Proposition 1.6, we prove that a generalization of this result holds for finite products R of full matrix rings over local rings; namely, an ideal A is finitely generated as a right or left ideal iff A is generated by a central idempotent. We also note a theorem going back to Nakayama, Goursaud, and the author that every factor ring of R is right PF iff R is a uniserial ring. (See Theorem 5.1.).

On app skew generalized power series rings

2013 ◽  
Vol 50 (4) ◽  
pp. 436-453
Author(s):  
A. Majidinya ◽  
A. Moussavi
Keyword(s):  
Power Series ◽  
Left Ideal ◽  
Commutative Monoid ◽  
Power Series Ring ◽  
Generalized Power Series ◽  
Series Ring ◽  
Monoid Homomorphism ◽  
Power Series Rings ◽  
Armendariz Ring ◽  
Left Annihilator

By [12], a ring R is left APP if R has the property that “the left annihilator of a principal ideal is pure as a left ideal”. Equivalently, R is a left APP-ring if R modulo the left annihilator of any principal left ideal is flat. Let R be a ring, (S, ≦) a strictly totally ordered commutative monoid and ω: S → End(R) a monoid homomorphism. Following [16], we show that, when R is a (S, ω)-weakly rigid and (S, ω)-Armendariz ring, then the skew generalized power series ring R[[S≦, ω]] is right APP if and only if rR(A) is S-indexed left s-unital for every S-indexed generated right ideal A of R. We also show that when R is a (S, ω)-strongly Armendariz ring and ω(S) ⫅ Aut(R), then the ring R[[S≦, ω]] is left APP if and only if ℓR(∑a∈A ∑s∈SRωs(a)) is S-indexed right s-unital, for any S-indexed subset A of R. In particular, when R is Armendariz relative to S, then R[[S≦]] is right APP if and only if rR(A) is S-indexed left s-unital, for any S-indexed generated right ideal A of R.

Complemented Banach Algebras

1964 ◽  
Vol 16 ◽  
pp. 149-150
Author(s):  
A. Olubummo
Keyword(s):  
Banach Algebra ◽  
Left Ideal ◽  
Banach Algebras ◽  
Complex Banach Algebra ◽  
Left Annihilator

Let A be a complex Banach algebra and Lr (Ll) be the lattice of all closed right (left) ideals in A. Following Tomiuk (5), we say that A is a right complemented algebra if there exists a mapping I —> IP of Lτ into Lr such that if I ∊ Lr, then I ∩ Ip = (0), (Ip)p = I, I ⴲ Ip = A and if I1, I2 ∊ Lr with I1 ⊆ I2 then .If in a Banach algebra A every proper closed right ideal has a non-zero left annihilator, then A is called a left annihilator algebra. If, in addition, the corresponding statement holds for every proper closed left ideal and r(A) = (0) = l(A), A is called an annihilator algebra (1).

scholarly journals Quasi-Baer ring extensions and biregrular rings

2000 ◽  
Vol 61 (1) ◽  
pp. 39-52 ◽  
Author(s):  
Gary F. Birkenmeier ◽  
Jin Yong Kim ◽  
Jae Keol Park
Keyword(s):  
Left Ideal ◽  
Regular Ring ◽  
Nonempty Subset ◽  
Baer Ring ◽  
Principal Ideals ◽  
Ring Extensions ◽  
Left Annihilator

A ring R with unity is called a (quasi-) Baer ring if the left annihilator of every (left ideal) nonempty subset of R is generated (as a left ideal) by an idempotent. Armendariz has shown that if R is a reduced PI-ring whose centre is Baer, then R is Baer. We generalise his result by considering the broader question: when does the (quasi-) Baer condition extend to a ring from a subring? Also it is well known that a regular ring is Baer if and only if its lattice of principal right ideals is complete. Analogously, we prove that a biregular ring is quasi-Baer if and only if its lattice of principal ideals is complete.

Sign in / Sign up

Export Citation Format

Share Document