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We prove that torsion in the abelianizations of open normal subgroups in finitely presented pro-$p$ groups can grow arbitrarily fast. By way of contrast in $\mathbb Z_p$- analytic groups the torsion growth is at most polynomial.

Group Theory · Mathematics 2021-06-29 Nikolay Nikolov

Using Rees index, the subsemigroup growth of free semigroups is investigated. Lower and upper bounds for the sequence are given and it is shown to have superexponential growth of strict type $n^n$ for finite free rank greater than 1. It is…

Group Theory · Mathematics 2014-09-30 Alex Bailey , Martin Finn-Sell , Robert Snocken

We present two quite different algorithms to compute the number of elements in the sphere of radius $n$ of Thompson's group $F$ with standard generating set. The first of these requires exponential time and polynomial space, but…

Group Theory · Mathematics 2012-05-16 Murray Elder , Eric Fusy , Andrew Rechnitzer

A group $G$ is said to be equationally Noetherian if every system of equations in $G$ is equivalent to a finite subsystem. We show that all free-by-cyclic groups are equationally Noetherian. As a corollary, we deduce that the set of…

Group Theory · Mathematics 2025-12-04 Monika Kudlinska , Motiejus Valiunas

We review localization with non-Hermitian time evolution as applied to simple models of population biology with spatially varying growth profiles and convection. Convection leads to a constant imaginary vector potential in the…

Disordered Systems and Neural Networks · Physics 2009-10-31 Karin A. Dahmen , David R. Nelson , Nadav M. Shnerb

This paper studies the classes of semigoups and monoids with context-free and deterministic context-free word problem. First, some examples are exhibited to clarify the relationship between these classes and their connection with the…

Group Theory · Mathematics 2019-03-26 Tara Brough , Alan J. Cain , Markus Pfeiffer

We study the averaging of fronts moving with positive oscillatory normal velocity, which is periodic in space and stationary ergodic in time. The problem can be reformulated as the homogenization of coercive level set Hamilton-Jacobi…

Analysis of PDEs · Mathematics 2014-08-12 W. Jing , P. E. Souganidis , H. V. Tran

This note provides an alternate account of Calegari's rationality theorem for stable commutator length in free groups.

Geometric Topology · Mathematics 2016-09-13 Noel Brady , Matt Clay , Max Forester

We derive a lower and an upper bound for the rank of the finite part of operator $K$-theory groups of maximal and reduced $C^*$-algebras of finitely generated groups. The lower bound is based on the amount of polynomially growing conjugacy…

K-Theory and Homology · Mathematics 2017-05-24 Süleyman Kağan Samurkaş

For d=2n+1 a positive odd integer, we consider sequences of arithmetic subgroups of SO_0(d,1) and Spin(d,1) yielding corresponding hyperbolic manifolds of finite volume and show that, under appropriate and natural assumptions, the torsion…

Differential Geometry · Mathematics 2019-06-25 Werner Mueller , Frédéric Rochon

In topic modeling, many algorithms that guarantee identifiability of the topics have been developed under the premise that there exist anchor words -- i.e., words that only appear (with positive probability) in one topic. Follow-up work has…

Machine Learning · Statistics 2016-11-16 Kejun Huang , Xiao Fu , Nicholas D. Sidiropoulos

In this article we give a sufficient and necessary condition to determine wether or not an element of the free group induces a non-trivial element of the free Burnside group of sufficiently large odd exponent. This criterion can be stated…

Group Theory · Mathematics 2019-09-02 Rémi Coulon

A locally compact group G is said to be Hermitian if every selfadjoint element of L^1(G) has real spectrum. Using Halmos' notion of capacity in Banach algebras and a result of Jenkins, Fountain, Ramsay and Williamson we will put a bound on…

Functional Analysis · Mathematics 2013-05-28 Rui Palma

Structure monoids and groups are algebraic invariants of equational varieties. We show how to construct presentations of these objects from coherent categorifications of equational varieties, generalising several results of Dehornoy. We…

Category Theory · Mathematics 2008-02-26 Jonathan A. Cohen

In this paper, we study the sub-Riemannian problem associated with contact structures on connected, simply connected, solvable, non-nilpotent, regular three-dimensional Lie groups. For these groups, the vertical component of the Hamiltonian…

Optimization and Control · Mathematics 2026-02-23 Adriano Da Silva , Lino Grama , Douglas Duarte Novaes , Margarita Quispe Tusco

This work introduces the first in-depth study of h-free and h-full elements in abelian monoids, providing a unified approach for understanding their role in various mathematical structures. Let m be an element of an abelian monoid, with…

Number Theory · Mathematics 2025-06-03 Sourabhashis Das , Wentang Kuo , Yu-Ru Liu

The space $\mathcal{G}_n$ of $n$-marked groups provides a natural framework for studying algebraic and geometric invariants under deformation. In general, the growth rate is not continuous on $\mathcal{G}_n$. In this paper, we investigate…

Group Theory · Mathematics 2026-02-18 Tomoshige Yukita

This is a survey of recent progress in several areas of combinatorial algebra. We consider combinatorial problems about free groups, polynomial algebras, free associative and Lie algebras. Our main idea is to study automorphisms and, more…

Group Theory · Mathematics 2016-09-07 Alexander A. Mikhalev , Vladimir Shpilrain , Jie-Tai Yu

In this paper, we focus on exploiting the group structure for large-dimensional factor models, which captures the homogeneous effects of common factors on individuals within the same group. In view of the fact that datasets in…

Methodology · Statistics 2024-05-14 Yong He , Xiaoyang Ma , Xingheng Wang , Yalin Wang

Let $F$ be a free group of positive, finite rank and let $\Phi\in Aut(F)$ be a polynomial-growth automorphism. Then $F\rtimes_\Phi\mathbb Z$ is strongly thick of order $\eta$, where $\eta$ is the rate of polynomial growth of $\phi$. This…

Group Theory · Mathematics 2020-01-29 Mark Hagen