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Related papers: Essential Dimension of Small Finite Groups

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We prove that the essential dimension of the spinor group Spin_n grows exponentially with n; in particular, we give a precise formula for this essential dimension when n is not divisible by 4. We use this result to show that the number of…

Algebraic Geometry · Mathematics 2017-02-22 Patrick Brosnan , Zinovy Reichstein , Angelo Vistoli

For a finite group $G$ let $\sigma(G)$ (the "sum" of $G$) be the least number of proper subgroups of $G$ whose set-theoretical union is equal to $G$, and $\sigma(G)=\infty$ if $G$ is cyclic. We say that a group $G$ is $\sigma$-elementary if…

Group Theory · Mathematics 2011-12-30 Martino Garonzi

We present a characterization of the finite groups in which all real classes have prime powers size.

Group Theory · Mathematics 2022-12-06 Lorenzo Bonazzi

We summarize what is currently known about ed$(G)$ and RD$(G)$ for finite groups $G$ over $\mathbb{C}$ (i.e. in characteristic 0). In Appendix A, we also give an argument which improves the known bound on RD(PSL$(2,\mathbb{F}_{11})$).

Algebraic Geometry · Mathematics 2023-12-08 Alexander J. Sutherland

Given a finite group $G$, we denote by $L(G)$ the subgroup lattice of $G$ and by ${\rm Isolated}(G)$ the set of isolated subgroups of $G$. In this note, we describe finite groups $G$ such that $|{\rm Isolated}(G)|=|L(G)|-k$, where…

Group Theory · Mathematics 2021-11-30 Marius Tărnăuceanu

This paper studies effective separability for subgroups of finitely generated nilpotent groups and more broadly effective subgroup separability of finitely generated nilpotent groups. We provide upper and lower bounds that are polynomial…

Group Theory · Mathematics 2018-10-02 Jonas Deré , Mark Pengitore

One of the important open problems in the theory of central simple algebras is to compute the essential dimension of $\operatorname{GL}_n/\mu_m$, i.e., the essential dimension of a generic division algebra of degree $n$ and exponent…

Group Theory · Mathematics 2015-04-01 Shane Cernele , Zinovy Reichstein , Athena Nguyen

In this paper we prove that free solvable groups have finite Krull dimension. In fact, this is true for much wider class of solvable groups, termed rigid groups. Along the way we study the algebraic structure of the limit solvable groups…

Group Theory · Mathematics 2008-08-22 A. Myasnikov , N. Romanovskiy

This paper investigates the critical group of a faithful representation of a finite group. It computes the order of the critical group in terms of the character values, and gives some restrictions on its subgroup structure. It also computes…

Combinatorics · Mathematics 2016-10-14 Christian Gaetz

We find upper bounds for the essential dimension of various moduli stacks of $\sln$-bundles over a curve. When $n$ is a prime power, our calculation computes the essential dimension of the stack of stable bundles exactly and the essential…

Algebraic Geometry · Mathematics 2009-08-04 Ajneet Dhillon , Nicole Lemire

By using the structure and some properties of extraspecial and generalized/almost extraspecial $p$-groups, we explicitly determine the number of elements of specific orders in such groups. As a consequence, one may find the number of cyclic…

Group Theory · Mathematics 2024-05-08 Mihai-Silviu Lazorec

A finite semifield $D$ is a finite nonassociative ring with identity such that the set $D^*=D\setminus\{0\}$ is closed under the product. In this paper we obtain a computer-assisted description of all 64-element finite semifields, which…

Rings and Algebras · Mathematics 2008-08-08 I. F. Rúa , Elías F. Combarro , J. Ranilla

We use a recent advance in birational geometry to prove new lower bounds on the essential dimension of some finite groups.

Algebraic Geometry · Mathematics 2018-03-28 Zinovy Reichstein

We characterize finite $p$-groups $G$ of order up to $p^7$ for which the group of central automorphisms fixing the center element-wise is of minimum possibe order.

Group Theory · Mathematics 2015-03-17 Deepak Gumber , Mahak Sharma

An $integral$ of a group $G$ is a group $H$ whose derived group (commutator subgroup) is isomorphic to $G$. This paper discusses integrals of groups, and in particular questions about which groups have integrals and how big or small those…

Group Theory · Mathematics 2018-08-24 João Araújo , Peter J. Cameron , Carlo Casolo , Francesco Matucci

We prove that for geometrically finite groups cohomological dimension of the direct product of a group with itself equals 2 times the cohomological dimension dimension of the group.

Group Theory · Mathematics 2022-04-28 Alexander Dranishnikov

In this paper we develop the theory of essential dimension of group schemes over an integral base. Shortly we concentrate over a local base. As a consequence of our theory we give a result of invariance of the essential dimension over a…

Algebraic Geometry · Mathematics 2017-09-08 Dajano Tossici

We give an explicit bound on orders of finite subgroups of Cremona group of rank three over $\mathbb{Q}$.

Algebraic Geometry · Mathematics 2026-02-09 Alexandr Zaitsev

In this paper we obtain significant bounds for the number of maximal subgroups of a given index of a finite group. These results allow us to give new bounds for the number of random generators needed to generate a finite $d$-generated group…

Group Theory · Mathematics 2023-03-14 A. Ballester-Bolinches , R. Esteban-Romero , P. Jiménez-Seral

We classify all finite groups with five relative commutativity degrees. Also, we give a partial answer to our previous conjecture on a lower bound of the number of relative commutativity degrees of finite groups.

Group Theory · Mathematics 2019-12-11 Mohammad Farrokhi Derakhshandeh Ghouchan