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Related papers: Finite simple groups of small essential dimension

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For a finite group $G$, let $\text{rdim}(G)$ denote the smallest dimension of a faithful, complex linear representation of $G$. It is clear that $\text{rdim}(H)\leq \text{rdim}(G)$ for any subgroup $H$ of $G$. We consider $G$ with the…

Group Theory · Mathematics 2022-06-23 Jonathan Cohen

Let $G$ be a finite group. A proper subgroup $H$ of $G$ is said to be large if the order of $H$ satisfies the bound $|H|^3 \ge |G|$. In this note we determine all the large maximal subgroups of finite simple groups, and we establish an…

Group Theory · Mathematics 2014-07-04 S. Hassan Alavi , Timothy C. Burness

We discuss essential dimension of group schemes, with particular attention to infinitesimal group schemes. We prove that the essential dimension of a group scheme of finite type over a field k is at least equal to the difference between the…

Algebraic Geometry · Mathematics 2010-10-26 Dajano Tossici , Angelo Vistoli

We give an upper bound for the essential dimension of a smooth unipotent algebraic group over an arbitrary field. We also show that over a field $k$ which is finitely generated over a perfect field, a smooth unipotent algebraic $k$-group is…

Number Theory · Mathematics 2010-12-15 Nguyen Duy Tan

We show that the classification of simple finite group schemes over an algebraically closed field reduces to the classification of abstract simple finite groups and of simple restricted Lie algebras in positive characteristic. Both these…

Algebraic Geometry · Mathematics 2015-03-13 Filippo Viviani

Let K be an arbitrary field. We will determine explicitly all the nontrivial finite groups of essential dimension one over K.

Algebraic Geometry · Mathematics 2007-05-23 Huah Chu , Shou-Jen Hu , Ming-chang Kang , Jiping Zhang

We rule out a certain $9$-dimensional algebra over an algebraically closed field to be the basic algebra of a block of a finite group, thereby completing the classification of basic algebras of dimension at most $12$ of blocks of finite…

Representation Theory · Mathematics 2020-05-06 Markus Linckelmann , William Murphy

The category of linear algebraic groups admits non-surjective epimorphisms. For simple algebraic groups of rank $2$ defined over algebraically closed fields, we show that the minimal dimension of a closed epimorphic subgroup is $3$.

Group Theory · Mathematics 2023-06-30 Iulian I. Simion , Donna M. Testerman

We define and study the essential dimension of an algebraic stack. We compute the essential dimension of the stacks Mgn and MgnBar of smooth, or stable, n-pointed curves of genus g. We also prove a general lower bound for the essential…

Algebraic Geometry · Mathematics 2007-05-23 Patrick Brosnan , Zinovy Reichstein , Angelo Vistoli

We study the essential dimension of a finite group G over a field K. A generalization of the central extension theorem of Buhler and Reichstein (Compositio Math. 106 (1997) 159-179, Theorem 5.3) is obtained. We also get lower bounds of…

Algebraic Geometry · Mathematics 2007-05-23 Ming-chang Kang

We classify, up to isomorphism and up to equivalence, division gradings (by abelian groups) on finite-dimensional simple real algebras. Gradings on finite-dimensional simple algebras are determined by division gradings, so our results give…

Rings and Algebras · Mathematics 2015-12-23 Adrián Rodrigo-Escudero

We classify, up to equivalence, all finite-dimensional simple graded division algebras over the field of real numbers. The grading group is any finite abelian group.

Rings and Algebras · Mathematics 2015-06-09 Yuri Bahturin , Mikhail Zaicev

This paper reproduces the text of a part of the Author's DPhil thesis. It gives a proof of the classification of non-trivial, finite homogeneous geometries of sufficiently high dimension which does not depend on the classification of the…

Group Theory · Mathematics 2017-01-19 David M. Evans

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

The representation dimension of a finite group $G$ is the minimal dimension of a faithful complex linear representation of $G$. We prove that the representation dimension of any finite group $G$ is at most $\sqrt{|G|}$ except if $G$ is a…

Group Theory · Mathematics 2026-02-18 Alexander Moretó

Bounded-cohomological dimension of groups is a relative of classical cohomological dimension, defined in terms of bounded cohomology with trivial coefficients instead of ordinary group cohomology. We will discuss constructions that lead to…

Group Theory · Mathematics 2015-09-09 Clara Loeh

Finite semisimple group algebras for which all the minimal ideals are easily computable dimension (ECD) are characterized and some lower bounds for the minimum Hamming distance of group codes in these algebras are offered. Examples…

Representation Theory · Mathematics 2024-08-08 E. J. García-Claro

We consider the dimensions of finite type of representations of a partially ordered set, i.e. such that there is only finitely many isomorphism classes of representations of this dimension. We give a criterion for a dimension to be of…

Representation Theory · Mathematics 2012-01-24 Yuriy A. Drozd , Eugene A. Kubichka

Given a finite smooth group scheme $G$ over a field of characteristic $p > 0$, we show that the essential dimension of $G$ at $p$ is $0$ when $p$ does not divide the order of $G$, and $1$ when it does.

Group Theory · Mathematics 2018-03-28 Zinovy Reichstein , Angelo Vistoli

We determine the smallest irreducible Brauer characters for finite quasi-simple orthogonal type groups in non-defining characteristic. Under some restrictions on the characteristic we also prove a gap result showing that the next larger…

Representation Theory · Mathematics 2023-06-22 Kay Magaard , Gunter Malle