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It is shown that in the units of augmentation one of an integral group ring $\mathbb{Z} G$ of a finite group $G$, a noncyclic subgroup of order $p^{2}$, for some odd prime $p$, exists only if such a subgroup exists in $G$. The corresponding…

Representation Theory · Mathematics 2007-05-23 Martin Hertweck

This article focuses on the study of cut groups, i.e., the groups which have only trivial central units in their integral group ring. We provide state of art for cut groups. The results are compiled in a systematic manner and have also been…

Rings and Algebras · Mathematics 2025-05-15 Seema Chahal , Sugandha Maheshwary

This note studies the Burnside problem for homeomorphism groups of compact connected manifolds. For surfaces, we prove that the identity component of the homeomorphism group is torsion-free precisely when the surface is not the sphere,…

Geometric Topology · Mathematics 2026-04-24 Donggyun Seo

We prove that, given a torsion-free relatively hyperbolic group G with non-relatively-hyperbolic peripherals, isomorphic finite index subgroups of G have the same index. This applies for instance to fundamental groups of finite-volume…

Group Theory · Mathematics 2025-09-05 Nir Lazarovich , Gon Rahamim , Alessandro Sisto

The purpose of this paper is to investigate the finite Frobenius groups with "perfect order classes"; that is, those for which the number of elements of each order is a divisor of the order of the group. If a finite Frobenius group has…

Group Theory · Mathematics 2023-07-13 James McCarron

In this paper we study distortion of various well-known embeddings of finitely generated torsion-free nilpotent groups $G$ into unitriangular groups $UT_n(\mathbb{Z})$. We also provide a polynomial time algorithm for finding distortion of a…

Group Theory · Mathematics 2016-07-11 Funda Gul , Alexei G. Myasnikov , Mahmood Sohrabi

In this article we explore a non-abelian torsion theory in the category of preordered groups: the objects of its torsion-free subcategory are the partially ordered groups, whereas the objects of the torsion subcategory are groups (with the…

Category Theory · Mathematics 2021-04-13 Marino Gran , Aline Michel

There is a natural action of the braid group on the symmetric matrices with units on the diagonal, appearing in various fields as Singularity Theory, Frobenius Manifolds or Isomonodromic deformations of certain classes of linear…

Mathematical Physics · Physics 2007-05-23 Alexandre Stefanov

The Addition Theorem for the algebraic entropy of group endomorphisms of torsion abelian groups was proved in [4]. Later, this result was extended to all abelian groups [3] and, recently, to all torsion finitely quasihamiltonian groups [7].…

Group Theory · Mathematics 2022-09-13 Menachem Shlossberg

To initiate a systematic study on the applications of perfectoid methods to Noetherian rings, we introduce the notions of perfectoid towers and their tilts. We mainly show that the tilting operation preserves several homological invariants…

Commutative Algebra · Mathematics 2025-10-22 Shinnosuke Ishiro , Kei Nakazato , Kazuma Shimomoto

In the present paper, the structure of a finite group $G$ having a nonnormal T.I. subgroup $H$ which is also a Hall $\pi$-subgroup is studied. As a generalization of a result due to Gow, we prove that $H$ is a Frobenius complement whenever…

Group Theory · Mathematics 2018-06-05 M. Yasir Kızmaz

The goal of the present paper is to push forward the frontiers of computations on Farrell-Tate cohomology for arithmetic groups. The conjugacy classification of cyclic subgroups is reduced to the classification of modules of group rings…

K-Theory and Homology · Mathematics 2022-10-20 Bui Anh Tuan , Alexander D. Rahm , Matthias Wendt

We establish structure results for Frobenius kernels of automorphism group schemes for surfaces of general type in positive characteristics. It turns out that there are surprisingly few possibilities. This relies on properties of the famous…

Algebraic Geometry · Mathematics 2023-09-13 Stefan Schröer , Nikolaos Tziolas

If $R$ is a topological ring then $R^{\ast}$, the group of units of $R$, with the subspace topology is not necessarily a topological group. This leads us to the following natural definition: By an \emph{absolute topological ring} we mean a…

Commutative Algebra · Mathematics 2025-05-23 Abolfazl Tarizadeh

We show that for many classical knots one can find generalized torsion in the fundamental group of its complement, commonly called the knot group. It follows that such a group is not bi-orderable. Examples include all torus knots, the…

Algebraic Topology · Mathematics 2019-08-15 Geoff Naylor , Dale Rolfsen

We classify the groups quasi-isometric to a group generated by finite-order elements within the class of one-ended hyperbolic groups which are not Fuchsian and whose JSJ decomposition over two-ended subgroups does not contain rigid vertex…

Geometric Topology · Mathematics 2018-12-19 Emily Stark

We give an analog of Frobenius' theorem about the factorization of the group determinant on the group algebra of finite abelian groups and we extend it into dihedral groups and generalized quaternion groups. Furthermore, we describe the…

Representation Theory · Mathematics 2014-05-09 N. Yamaguchi

The aim of this paper is to study the group of isomorphism classes of torsors of finite flat group schemes of rank 2 over a commutative ring $R$. This, in particular, generalises the group of quadratic algebras (free or projective), which…

Algebraic Geometry · Mathematics 2019-02-20 Ilia Pirashvili

The Grothendieck-Serre conjecture predicts that every generically trivial torsor under a reductive group $G$ over a regular semilocal ring $R$ is trivial. We establish this for unramified $R$ granted that $G^{\mathrm{ad}}$ is totally…

Algebraic Geometry · Mathematics 2025-11-24 Kestutis Cesnavicius , Roman Fedorov

The lattice of subgroups of a group is the subject of numerous results revolving around the central theme of decomposing the group into "chunks" (subquotients) that can then be compared to one another in various ways. Examples of results in…

Quantum Algebra · Mathematics 2016-10-14 Alexandru Chirvasitu , Souleiman Omar Hoche , Paweł Kasprzak