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Related papers: On minimal non-sofic and $\omega$-non-sofic groups

200 papers

Motivated by intuitive properties of physical quantities, the notion of a non-anomalous semigroup is formulated. These are totally ordered semigroups where there are no `infinitesimally close' elements. The real numbers are then defined as…

History and Overview · Mathematics 2016-07-21 Damon Binder

We define a class of finite groups based on the properties of the closed twins of their power graphs and study the structure of those groups. As a byproduct, we obtain results about finite groups admitting a partition by cyclic subgroups.

Group Theory · Mathematics 2024-12-23 Daniela Bubboloni , Nicolas Pinzauti

Every finite non-abelian group of order $n$ has a non-central element whose centralizer has order exceeding $n^{1/3}$. The proof does not rely on the classification of finite simple groups, yet it uses the Feit-Thompson theorem.

Group Theory · Mathematics 2020-07-23 Daniel Palacín

Let $A$ and $G$ be finite groups such that $A$ acts coprimely on $G$ by automorphisms. We provide a complete classification of a finite group $G$ in which every maximal $A$-invariant subgroup containing the normalizer of some $A$-invariant…

Group Theory · Mathematics 2024-08-05 Jiangtao Shi , Fanjie Xu

We study finite p-groups G of coclass upto 4 for which the group Aut_z(G) of all central automorphisms of G is of minimal possible order. As a consequence, we obtain very short and elementary proofs of main results of Sharma and Gumber [7].

Group Theory · Mathematics 2015-03-17 Deepak Gumber , Hemant Kalra

The existence of a countably compact group without non-trivial convergent sequences in ZFC alone is a major open problem in topological group theory. We give a ZFC example of a Boolean topological group G without non-trivial convergent…

General Topology · Mathematics 2018-12-27 Dmitri Shakhmatov , Víctor Hugo Yañez

For each nonnegative integer m we show that any closed, oriented topological four-manifold with fundamental group Z_{4m+2} and odd intersection form, with possibly seven exceptions, either admits no smooth structure or admits infinitely…

Geometric Topology · Mathematics 2024-06-14 R. Inanc Baykur , Andras I. Stipsicz , Zoltan Szabo

Let $\mathcal G$ denote the space of finitely generated marked groups. For any finitely generated group $G$, we construct a continuous, injective map $f$ from the space of subgroups $Sub(G)$ to $\mathcal G$ that sends conjugate subgroups to…

Group Theory · Mathematics 2024-03-27 D. Osin

We determine the structure of the finite groups with the property that every cyclic subgroup is the intersection of maximal subgroups, comparing this property with the one where all proper subgroups are intersections of maximal subgroups.

Group Theory · Mathematics 2025-08-07 Andrea Lucchini

Let G be an abelian group. For a subset A of G, Cyc(A) denotes the set of all elements x of G such that the cyclic subgroup generated by x is contained in A, and G is said to have the small subgroup generating property (abbreviated to SSGP)…

General Topology · Mathematics 2018-12-27 Dmitri Shakhmatov , Víctor Hugo Yañez

A Hausdorff topological group G is minimal if every continuous isomorphism f: G --> H between G and a Hausdorff topological group H is open. Significantly strengthening a 1981 result of Stoyanov, we prove the following theorem: For every…

General Topology · Mathematics 2009-11-21 Dikran Dikranjan , Anna Giordano Bruno , Dmitri Shakhmatov

In this paper we prove that every non-central subnormal subgroup of the multiplicative group of a weakly locally finite division ring contains free non-cyclic subgroups.

Rings and Algebras · Mathematics 2013-04-09 Bui Xuan Hai , Nguyen Kim Ngoc

In this paper we prove two new results about closed semigroups in the family of solvable groups H_{mn} that are semidirect products of R^m and R^n, and for which the structure homomorphism maps nontrivially into the center of Aut(R^n). The…

Group Theory · Mathematics 2013-12-31 Kevin Lui , Viorel Nitica , Siddharth Venkatesh

We show that the fundamental group of every enumeratively rationally connected closed symplectic manifold is finite. In other words, if a closed symplectic manifold has a non-zero Gromov-Witten invariant with two point insertions, then it…

Symplectic Geometry · Mathematics 2025-08-28 Alex Pieloch

For a convergence group equipped with an expanding coarse-cocycle, we construct finitely generated free subsemigroups, which we call $\textit{Bishop--Jones}$ $\textit{semigroups}$, of critical exponent arbitrarily close to but strictly less…

Group Theory · Mathematics 2025-03-11 Aleksander Skenderi

We provide new computations in bounded cohomology: A group is boundedly acyclic if its bounded cohomology with trivial real coefficients is zero in all positive degrees. We show that there exists a continuum of finitely generated…

Group Theory · Mathematics 2022-10-24 Francesco Fournier-Facio , Clara Loeh , Marco Moraschini

A countable group G is called k-linear sofic (for some 0 <k \le 1) if finite subsets of G admit "approximate representations" by complex invertible matrices in the normalized rank metric, so that non-identity elements are k-away from the…

Group Theory · Mathematics 2025-04-02 Keivan Mallahi-Karai , Maryam Mohammadi Yekta

We carry out a study of groups $G$ in which the index of any infinite subgroup is finite. We call them restricted-finite groups and characterize finitely generated not torsion restricted-finite groups. We show that every infinite…

Group Theory · Mathematics 2023-05-02 B. Taeri , M. R. Vedadi

The study of finite subgroups of a simple algebraic group $G$ reduces in a sense to those which are almost simple. If an almost simple subgroup of $G$ has a socle which is not isomorphic to a group of Lie type in the underlying…

Group Theory · Mathematics 2018-09-05 Alastair J. Litterick

We prove that there exist finitely presented, residually finite groups that are profinitely rigid in the class of all finitely presented groups but not in the class of all finitely generated groups. These groups are of the form $\Gamma…

Group Theory · Mathematics 2025-04-15 M. R. Bridson , A. W. Reid , R. Spitler