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We associate to each finite presentation of a group G a compact CW-complex that is a 3-manifold in the complement of a point, and whose fundamental group is isomorphic to G. We use this complex to define a notion of genus for G and give…

Group Theory · Mathematics 2011-12-01 Iain Aitchison , Lawrence Reeves

We characterize finite groups G generated by orthogonal transformations in a finite-dimensional Euclidean space V whose fixed point subspace has codimension one or two in terms of the corresponding quotient space V/G with its quotient…

Geometric Topology · Mathematics 2017-11-02 Christian Lange

Let $G$ be a finitely generated group. We prove that the $n$-fold tensor product $G^{\otimes n}$ is finite (resp. polycyclic) if and only $G$ is finite (resp. polycyclic). Further, assuming that $G$ is finitely presented, we show that…

Group Theory · Mathematics 2025-10-28 R. Bastos , G. Ortega

We exhibit a family of metrizable manifolds such that any finite group appears as the fundamental group of one of them. These spaces are especially interesting as they can be easily visualized, as opposed to classical examples of spaces…

Algebraic Topology · Mathematics 2024-11-12 Luca Tanganelli Castrillón

In this note we introduce the notion of a transcendental group, that is, a subgroup $G$ of the topological group $\mathbb{C}$ of all complex numbers such that every element of $G$ except $ 0$ is a transcendental number. All such topological…

General Topology · Mathematics 2021-12-24 Sidney A. Morris

We prove for residually finite groups the following long standing conjecture: the number of twisted conjugacy classes of an automorphism of a finitely generated group is equal (if it is finite) to the number of finite dimensional…

Group Theory · Mathematics 2012-05-01 Alexander Fel'shtyn , Evgenij Troitsky

Finite group theorists have established many formulas that express interesting properties of a finite group in terms of sums of characters of the group. An obstacle to applying these formulas is lack of control over the dimensions of…

Representation Theory · Mathematics 2016-12-07 Shamgar Gurevich , Roger Howe

In this paper we describe a class of highly entangled subspaces of a tensor product of finite dimensional Hilbert spaces arising from the representation theory of free orthogonal quantum groups. We determine their largest singular values…

Mathematical Physics · Physics 2019-02-27 Michael Brannan , Benoit Collins

A Coxeter group admits infinite-dimensional irreducible complex representations if and only if it is not finite or affine. In this paper, we provide a construction of some of those representations for certain Coxeter groups using some…

Representation Theory · Mathematics 2025-03-25 Hongsheng Hu

We classify irreducible unitary representations of the group of all infinite matrices over a $p$-adic field ($p\ne 2$) with integer elements equipped with a natural topology. Any irreducible representation passes through a group $GL$ of…

Representation Theory · Mathematics 2021-08-24 Yury A. Neretin

This expository article revolves around the question to find short presentations of finite simple groups. This subject is one of the most active research areas of group theory in recent times. We bring together several known results on…

Group Theory · Mathematics 2020-05-19 Yash Arora , Anupam Singh

We will determine all infinite $2$-locally finite groups as well as infinite $2$-groups with planar subgroup graph and show that infinite groups satisfying the chain conditions containing an involution do not have planar embeddings. Also,…

Group Theory · Mathematics 2014-03-04 Mehdi Rajabian , Mohammad Farrokhi Derakhshandeh Ghouchan , Ahmad Erfanian

Equationally compact subgroups of countable groups were introduced by Banaschewski. For all known cases the orbit closure of such a subgroup is a countable subset in the space of subgroups and has finite Cantor-Bendixson rank. We show that…

Group Theory · Mathematics 2016-08-19 Gabor Elek , Konrad Krolicki

In this paper we show that there exists an uncountable family of finitely generated simple groups with the same positive theory as any non-abelian free group. In particular, these simple groups have infinite $w$-verbal width for all…

A large class of positive finite presentations of the braid groups is found and studied. It is shown that no presentations but known exceptions in this class have the property that equivalent braid words are also equivalent under positive…

Geometric Topology · Mathematics 2007-05-23 Jae Woo Han , Ki Hyoung Ko

We study groups having the property that every non-abelian subgroup contains its centralizer. We describe various classes of infinite groups in this class, and address a problem of Berkovich regarding the classification of finite $p$-groups…

Group Theory · Mathematics 2016-06-07 Costantino Delizia , Heiko Dietrich , Primoz Moravec , Chiara Nicotera

Necessary and sufficient conditions for a group to possess a faithful irreducible representation are investigated

Representation Theory · Mathematics 2016-11-01 Fernando Szechtman , Anatoliy Tushev

We construct a finitely presented non-amenable group without free non-cyclic subgroups thus providing a finitely presented counterexample to von Neumann's problem. Our group is an extension of a group of finite exponent n >> 1 by a cyclic…

Group Theory · Mathematics 2007-05-23 A. Yu. Olshanskii , M. V. Sapir

A finite group $G$ is called *uniformly generated*, if whenever there is a (strictly ascending) chain of subgroups $1<\langle x_1\rangle<\langle x_1,x_2\rangle <\cdots<\langle x_1,x_2,\dots,x_d\rangle=G$, then $d$ is the minimal number of…

Group Theory · Mathematics 2019-05-31 S. P. Glasby

To any family of languages LAN, let us associate the class, denoted $\pi(\text{LAN})$, of finitely generated groups that admit a group presentation whose set of relators forms a language in LAN. We show that the class of L-presented groups,…

Group Theory · Mathematics 2025-08-26 Laurent Bartholdi , Leon Pernak , Emmanuel Rauzy
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