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Given a group word $w$ and a group $G$, the set of $w$-values in $G$ is denoted by $G_w$ and the verbal subgroup $w(G)$ is the one generated by $G_w$. In the present paper we consider profinite groups admitting a word $w$ such that the…

Group Theory · Mathematics 2021-02-16 João Azevedo , Pavel Shumyatsky

We compute the sheaf cohomology with constant $\mathbb{Z}_2$ coefficients of a concrete class of locally profinite sets of independent interest. We introduce $k$-sheer partitions to aid in constructions. It is also shown that questions of…

Logic · Mathematics 2026-04-14 Mark Schachner

Given a finitely generated linear group $G$ over $\mathbb{Q}$, we construct a simple group $\Gamma$ that has the same finiteness properties as $G$ and admits $G$ as a quasi-retract. As an application, we construct a simple group of type…

Group Theory · Mathematics 2025-10-03 Claudio Llosa Isenrich , Eduard Schesler , Xiaolei Wu

A pseudomodular group is a discrete subgroup $\Gamma \leq PGL(2,\mathbb{Q})$ which is not commensurable with $PSL(2,\mathbb{Z})$ and has cusp set precisely $\mathbb{Q}\cup\{\infty\}$. The existence of such groups was proved by Long and…

Geometric Topology · Mathematics 2020-05-26 Carmen Galaz-García

The residual finiteness growth of a group quantifies how well approximated the group is by its finite quotients. In this paper, we construct groups with arbitrarily large residual finiteness growth. We also demonstrate a new relationship…

Group Theory · Mathematics 2013-04-08 Khalid Bou-Rabee , Brandon Seward

We introduce a new class of Abelian groups which lies strictly between the classes of co-Hopfian groups and Dedekind-finite groups, calling these groups {\it Bassian-finite}. We prove the surprising fact that in the torsion case the…

Group Theory · Mathematics 2025-07-16 Peter V. Danchev , Patrick W. Keef

We classify and construct all multiplicity-free plethystic products of Schur functions. We also compute many new (infinite) families of plethysm coefficients, with particular emphasis on those near maximal in the dominance ordering and…

Representation Theory · Mathematics 2022-01-07 Christine Bessenrodt , Chris Bowman , Rowena Paget

This article presents the construction of finitely generated branch groups with uncountably many maximal subgroups using embedding techniques. This addresses a question posed by Grigorchuk.

Group Theory · Mathematics 2025-09-12 J. Moritz Petschick

We construct examples of free-by-cyclic hyperbolic groups which fiber in infinitely many ways over Z. The construction involves adding a specialized square 2-cell to a non-positively curved, squared 2-complex defined by labeled oriented…

Group Theory · Mathematics 2014-11-11 TaraLee Mecham , Antara Mukherjee

For every algebraically closed field $k$ and natural number $r$, we construct several algebraic varieties (over $k$) whose birational automorphism group contains every finite nilpotent group of class at most $2$, rank at most $r$ whose…

Algebraic Topology · Mathematics 2025-10-20 Dávid R. Szabó

Motivated by quotient algorithms, such as the well-known $p$-quotient or solvable quotient algorithms, we describe how to compute extensions $\tilde H$ of a finite group $H$ by a direct sum of isomorphic simple $\mathbb{Z}_p H$-modules such…

Group Theory · Mathematics 2020-11-26 Heiko Dietrich , Alexander Hulpke

In the present paper we study the following problem: how to construct a coherent orthoalgebra which has only a finite number of elements, but at the same time does not admit a bivaluation (i.e. a morphism with a codomain being an…

Quantum Physics · Physics 2009-06-16 Artur Ruuge , Fred Van Oystaeyen

Certain constructs allowed in Mizar articles cannot be represented in first-order logic but can be represented in higher-order logic. We describe a way to obtain higher-order theorem proving problems from Mizar articles that make use of…

Logic in Computer Science · Computer Science 2016-05-24 Chad Brown , Josef Urban

For a finite real reflection group $W$ we use non-crossing partitions of type $W$ to construct finite cell complexes with the homotopy type of the Milnor fiber of the associated $W$-discriminant $\Delta_W$ and that of the Milnor fiber of…

Group Theory · Mathematics 2018-12-19 Thomas Brady , Michael Falk , Colum Watt

The cohomology ring of a finite group, with coefficients in a finite field, can be computed by a machine, as Carlson has showed. Here "compute" means to find a presentation in terms of generators and relations, and involves only the…

Algebraic Topology · Mathematics 2009-05-20 Pierre Guillot

The maximum principle for holomirphic functions in the quantum ball is formulated. A proof can be found in [8] (see the bibliography).

Quantum Algebra · Mathematics 2007-05-23 S. Sinel'shchikov , L. Vaksman

We study pseudorandomness and pseudorandom generators from the perspective of logical definability. Building on results from ordinary derandomization and finite model theory, we show that it is possible to deterministically construct, in…

Logic in Computer Science · Computer Science 2023-04-25 Jan Dreier , Jamie Tucker-Foltz

A quasigroup $Q$ is called maximally nonassociative if for $x,y,z\in Q$ we have that $x\cdot (y\cdot z) = (x\cdot y)\cdot z$ only if $x=y=z$. We show that, with finitely many exceptions, there exists a maximally nonassociative quasigroup of…

Combinatorics · Mathematics 2021-07-09 Ales Drapal , Ian M. Wanless

We introduce higher strip deformations, which give a way of constructing affine deformations of discrete free groups in the image of the irreducible representation $\operatorname{PSL}_2\mathbb{R}\to \operatorname{SO}(2n,2n-1)$. We use the…

Geometric Topology · Mathematics 2022-05-31 Neža Žager Korenjak

We construct explicitly in any finite field of the form Fq[x]/(x^m-a) elements with multiplicative order at least 2^{(2m)^(1/2)}

Number Theory · Mathematics 2026-02-27 Roman Popovych