Derangements in Simple and Primitive Groups
نویسندگان
چکیده
We investigate the proportion of fixed point free permutations (derangements) in finite transitive permutation groups. This article is the first in a series where we prove a conjecture of Shalev that the proportion of such elements is bounded away from zero for a simple finite group. In fact, there are much stronger results. This article focuses on finite Chevalley groups of bounded rank. We also discuss derangements in algebraic groups and in more general primitive groups. These results have applications in questions about probabilistic generation of finite simple groups and maps between varieties over finite fields.
منابع مشابه
Bounds on the Number and Sizes of Conjugacy Classes in Finite Chevalley Groups with Applications to Derangements
We present explicit upper bounds for the number and size of conjugacy classes in finite Chevalley groups and their variations. These results have been used by many authors to study zeta functions associated to representations of finite simple groups, random walks on Chevalley groups, the final solution to the Ore conjecture about commutators in finite simple groups and other similar problems. I...
متن کاملBrandt extensions and primitive topologically periodic inverse topological semigroups
In this paper we find sufficient conditions on primitive inverse topological semigroup S under which: the inversion inv : (H(S)) (H(S)) is continuous; we show that every topologically periodic countable compact primitive inverse topological semigroups with closed H-classes is topologically isomorphic to an orthogonal sum P i2= Bi (Gi) of topological Brandt extensions Bi (Gi) of countably compac...
متن کاملPrime order derangements in primitive permutation groups
Let G be a transitive permutation group on a finite set Ω of size at least 2. An element of G is a derangement if it has no fixed points on Ω. Let r be a prime divisor of |Ω|. We say that G is r-elusive if it does not contain a derangement of order r, and strongly r-elusive if it does not contain one of r-power order. In this note we determine the r-elusive and strongly r-elusive primitive acti...
متن کاملCorrelation between condyle morphology and disk position of disc displacement in patients with TMJ internal derangements by magnetic resonance imaging
Background and Aims :The most frequent cause of TMJ dysfunction is internal derangement which that largely involves the function of the articular disc. Anterior disc displacement (ADD) is one of the major findings in TMJ internal derangement. Since the importance of knowledge of its etiology and also The role of all structural indicators association with TMD was not evaluated, in this researc...
متن کاملFlag-transitive Point-primitive symmetric designs and three dimensional projective special linear groups
The main aim of this article is to study (v,k,λ)-symmetric designs admitting a flag-transitive and point-primitive automorphism group G whose socle is PSL(3,q). We indeed show that the only possible design satisfying these conditions is a Desarguesian projective plane PG(2,q) and G > PSL(3,q).
متن کامل