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In this paper, we give the definition of {\em weakly locally finite} division rings and we show that the class of these rings strictly contains the class of locally finite division rings. Further, we study multiplicative subgroups in these…

Rings and Algebras · Mathematics 2013-05-21 Bui Xuan Hai , Mai Hoang Bien , Trinh Thanh Deo

We study those rings in which all invertible elements are weakly nil-clean calling them {\it UWNC rings}. This somewhat extends results due to Karimi-Mansoub et al. in Contemp. Math. (2018), where rings in which all invertible elements are…

Rings and Algebras · Mathematics 2024-02-06 Peter Danchev , Omid Hasanzadeh , Arash Javan , Ahmad Moussavi

Weak proregularity of an ideal in a commutative ring is a subtle generalization of the noetherian property of the ring. Weak proregularity is of special importance for the study of derived completion, and it occurs quite often in…

Commutative Algebra · Mathematics 2024-08-06 Amnon Yekutieli

In this paper, we introduce a class of $J$-quasipolar rings. Let $R$ be a ring with identity. An element $a$ of a ring $R$ is called {\it weakly $J$-quasipolar} if there exists $p^2 = p\in comm^2(a)$ such that $a + p$ or $a-p$ are contained…

Rings and Algebras · Mathematics 2018-12-11 M. B. Calci , S. Halicioglu , A. Harmanci

In this paper, we introduce and explore in-depth the notion of {\it weakly strongly 2-nil-clean rings} as a common non-trivial generalization of both strongly 2-nil-clean rings and strongly weakly nil-clean rings as defined and studied by…

Rings and Algebras · Mathematics 2025-09-09 Peter Danchev , Mina Doostalizadeh , Ahmad Moussavi

A semiring generalises the notion of a ring, replacing the additive abelian group structure with that of a commutative monoid. In this paper, we study a notion positioned between a ring and a semiring -- a semiring whose additive monoid is…

Rings and Algebras · Mathematics 2024-11-20 Peter F. Faul , Amartya Goswami , Gideo Joubert , Graham Manuell

It is known that strongly nilpotent matrices over a division ring are linearly triangularizable. We describe the structure of such matrices in terms of the strong nilpotency index. We apply our results on quasi-translation x + H such that…

Algebraic Geometry · Mathematics 2013-10-24 Michiel de Bondt

The notion of weighted $(b,c)$-inverse of an element in rings were introduced, very recently [Comm. Algebra, 48 (4) (2020): 1423-1438]. In this paper, we further elaborate on this theory by establishing a few characterizations of this…

Rings and Algebras · Mathematics 2020-10-20 Bibekananda Sitha , Jajati Keshari Sahoo , Ratikanta Behera

Let $G$ be a connected semisimple Lie group with its maximal compact subgroup $K$ being simply-connected. We show that the twisted equivariant $KK$-theory $KK^{\bullet}_{G}(G/K, \tau_G^G)$ of $G$ has a ring structure induced from the…

K-Theory and Homology · Mathematics 2021-06-30 Chi-Kwong Fok , Varghese Mathai

Let $R$ be a $G$-graded ring. In this article, we introduce two new concepts on graded rings, namely, weakly graded rings and invertible graded rings, and we discuss the relations between these concepts and several properties of graded…

Commutative Algebra · Mathematics 2021-01-19 Mashhoor Refai , R. Abu-Dawwas

A multiplicative hyperring is a well-known type of algebraic hyperstructures which extend a ring to a structure in which the addition is an operation but multiplication is a hyperoperation. Let G be a commutative multiplicative hyperring…

Rings and Algebras · Mathematics 2023-05-24 Mahdi Anbarloei

We give a constructive counterpart of the theorem of Andrunakievi\v{c} and Rjabuhin, which states that every reduced ring is a subdirect product of domains. As an application, we extract a constructive proof of the fact that every ring $A$…

Rings and Algebras · Mathematics 2024-08-20 Ryota Kuroki

It is emphasized that the existence of a very light axion is consistent with the strong CP invariance and cosmological and astrophysical constraints. The attempt to embed the very light axion in superstring models is discussed.

Astrophysics · Physics 2016-11-03 Jihn E. Kim

Let A be a commutative ring and E a non-zero A-module. Necessary and sufficient conditions are given for the trivial ring extension R of A by E to be either arithmetical or Gaussian. The possibility for R to be B{\'e}zout is also studied,…

Rings and Algebras · Mathematics 2015-07-09 Francois Couchot

We consider the class of all commutative reduced rings for which there exists a finite subset T of A such that all projections on quotients by prime ideals of A are surjective when restricted to T. A complete structure theorem is given for…

Commutative Algebra · Mathematics 2009-03-17 Antonio Avilés

We investigate modules over "systematic" rings. Such rings are "almost graded" and have appeared under various names in the literature; they are special cases of the G-systems of Grzeszczuk. We analyse their K-theory in the presence of…

K-Theory and Homology · Mathematics 2019-09-12 Thomas Huettemann , Zuhong Zhang

We study a ring containing a complete set of orthogonal idempotents as a generalized matrix ring via its Peirce decomposition. We focus on the case where some of the underlying bimodule homomorphisms are zero. Upper and lower triangular…

Rings and Algebras · Mathematics 2016-03-04 P. N. Anh , G. F. Birkenmeier , L. van Wyk

An alternative proof of Eliashberg-Gromov's C^0-rigidity theorem is presented and a new notion of weak Lie brackets for Hamiltonian vector fields is proposed and compared.

Symplectic Geometry · Mathematics 2011-01-25 S. Vazzoler , F. Cardin

We conjecture that for a strongly minimal theory T in a finite signature satisfying the Zilber Trichotomy, there are only three possibilities for the recursive spectrum of T: all countable models of T are recursively presentable; none of…

Logic · Mathematics 2012-06-19 Uri Andrews , Alice Medvedev

Weak coalgebra-Galois extensions are studied. A notion of an invertible weak entwining structure is introduced. It is proven that, within an invertible weak entwining structure, the surjectivity of the canonical map implies bijectivity…

Quantum Algebra · Mathematics 2007-05-23 Tomasz Brzezinski , Ryan B. Turner , Adam P. Wrightson
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