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Related papers: Etale extensions with finitely many subextensions

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The paper deals with ring extensions $R\subseteq S$ and the poset $[R,S]$ of their subextensions, with a special look at FCP extensions (extensions such that $[R,S]$ is Artinian and Noetherian). When the extension has FCP, we show that…

Commutative Algebra · Mathematics 2021-09-23 Gabriel Picavet , Martine Picavet-L'Hermitte

If $R\subseteq S$ is a ring extension of commutative unital rings, the poset $[R,S]$ of $R$-subalgebras of $S$ is called catenarian if it verifies the Jordan-H\"older property. This property has already been studied by Dobbs and Shapiro for…

Commutative Algebra · Mathematics 2019-11-26 Gabriel Picavet , Martine Picavet-L'Hermitte

The group ring of the automorphism group of a p-group is studied using the automorphism groups of subgroups and quotient groups of P.

Representation Theory · Mathematics 2007-11-12 John Martino , Stewart Priddy

This paper is a contribution to the study of extensions of arbitrary models of ZF (Zermelo-Fraenkel set theory), with no regard to countability or well-foundedness of the models involved. We present some new constructions of certain types…

Logic · Mathematics 2026-04-07 Ali Enayat

We study automorphisms of the affine line over rings like ZZ/p^n.

Number Theory · Mathematics 2013-11-06 Taylor Dupuy

In this paper, we examine the behavior of ideal-adic separatedness and completeness under certain ring extensions using trace map. Then we prove that adic completeness of a base ring is hereditary to its ring extension under reasonable…

Commutative Algebra · Mathematics 2021-05-25 Kei Nakazato , Kazuma Shimomoto

We study Lie rings definable in a finite-dimensional theory, extending the results for the finite Morley rank case. In particular, we prove a classification of Lie rings of dimension up to four in the NIP or connected case. In…

Logic · Mathematics 2025-11-11 Moreno Invitti

A ringed finite space is a ringed space whose underlying topological space is finite. The category of ringed finite spaces contains, fully faithfully, the category of finite topological spaces and the category of affine schemes. Any ringed…

Algebraic Geometry · Mathematics 2014-10-13 Fernando Sancho de Salas

Let $\mathfrak{P}$ be a topological property. We study the relation between the order structure of the set of all $\mathfrak{P}$-extensions of a completely regular space $X$ with compact remainder (partially ordered by the standard partial…

General Topology · Mathematics 2015-02-17 M. R. Koushesh

We introduce and study $\mu$-elements, that generalize a lattice-theoretic abstraction (namely, essential elements) of essential ideals of rings, essential submodules of modules, and dense subsets of topological spaces. Exploring several…

Rings and Algebras · Mathematics 2025-03-11 Elena Caviglia , Amartya Goswami , Luca Mesiti

We study the arithmetic aspects of the finite group of extensions of abelian varieties defined over a number field. In particular, we establish relations with special values of L-functions and congruences between modular forms.

Number Theory · Mathematics 2015-06-29 Matthew A. Papanikolas , Niranjan Ramachandran

In this note, we prove that there exist infinite dimensional excellent rings.

Commutative Algebra · Mathematics 2018-05-08 Hiromu Tanaka

We describe derivations of several important associative and Lie rings of infinite matrices over general rings of coefficients.

Rings and Algebras · Mathematics 2023-10-19 O. Bezushchak

We prove a new extension result for $QB-$rings that allows us to examine extensions of rings where the ideal is purely infinite and simple. We then use this result to explore various constructions that provide new examples of $QB-$rings.…

Rings and Algebras · Mathematics 2007-05-23 Pere Ara , Gert K. Pedersen , Francesc Perera

We introduce several new constructions of finite posets with the number of linear extensions given by generalized continued fractions. We apply our results to the problem of the minimum number of elements needed for a poset with a given…

Combinatorics · Mathematics 2024-08-01 Swee Hong Chan , Igor Pak

In 1995, E. Jespers, G. Leal and C. Polcino Milies classified all finite ring alternative loops (RA loops for short) which are not direct products of proper subloops. In this paper we extend this result to finitely generated RA loops and…

Rings and Algebras · Mathematics 2025-06-23 Mariana Cornelissen , Cesar Polcino Milies

Motivated by a valuation theorem, recently obtained by Rangachev, we study the \'etale extensions $A\subset B$ of polynomial rings over an algebraically closed field of characteristic zero, such that the integral closure $\overline{A}$ is a…

Algebraic Geometry · Mathematics 2024-04-12 Lázaro O. Rodríguez Díaz

The present paper introduces and studies some new types of rings and ideals such as completely nilary rings ( resp. completely nilary ideals ), weakly nilary ideals. Some properties of each are obtained and some characterizations of each…

Rings and Algebras · Mathematics 2022-08-19 Omar A. Al-Mallah , Hafed M. Al-Nogashi- Nooman Jarboui

In this article we present an extensive survey on the developments in the theory of non-abelian finite groups with abelian automorphism groups, and pose some problems and further research directions.

Group Theory · Mathematics 2017-08-03 Rahul Dattatraya Kitture , Manoj K. Yadav

In the note we construct a family of \'etale coverings of the affine line. More specifically, let $F$ be a finite field of characteristic $p$ and suppose that the cardinality of $F$ is at least 4. Let $A = F[T]$ be the polynomial ring in…

alg-geom · Mathematics 2015-06-30 Kirti Joshi