Lower signalizer lattices in alternating and symmetric groups

نویسندگان

  • Michael Aschbacher
  • Robert M. Guralnick
  • M. Aschbacher
چکیده

We prove that the subgroup lattices of finite alternating and symmetric groups do not contain so-called lower signalizer lattices in the class D. This result is one step in a program to show that the lattices in the class D are not isomorphic to an interval in the subgroup lattice of any finite group. In 1980 in [13], Palfy and Pudlak proved that the following two statements are equivalent: (1) Each nonempty finite lattice is isomorphic to an interval in the lattice of subgroups of a finite group. (2) Each finite lattice is isomorphic to the lattice of congruences of some finite algebra. Given a group G and a subgroup H of G, write OG.H/ for the lattice of overgroups ofH in G, and define a finite subgroup interval lattice to be a lattice of the form OG.H/ for some finite group G and subgroup H of G. In the thirty years since [13] appeared, the question of whether each finite lattice is a finite subgroup interval lattice has remained open and of significant interest. The general consensus seems to be that the answer is negative, and indeed that finite subgroup interval lattices constitute a small subclass of the class of all finite lattices. Early work on the question centered on so-called M-lattices, the lattices of depth 2. Probably the high point of this effort is the reduction (in 1997 by Baddeley and Lucchini in [10]) of the existence of M-lattices as finite group interval lattices, to various questions about finite simple groups. Each finite lattice ƒ has a greatest member1 and least member 0. Set ƒ D ƒ 10;1o. Given a positive integerm, write.m/ for the lattice of subsets of an m-set. Given finite latticesƒ1 andƒ2, writeƒ1 ƒ2 for the latticeƒ such thatƒ This work was partially supported by NSF DMS-0504852 and NSF DMS-0969009. Brought to you by | California Institute of Technology (California Institute of Technology) Authenticated | 172.16.1.226 Download Date | 5/25/12 4:50 PM

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A signalizer functor theorem for groups of finite Morley rank

There is a longstanding conjecture, due to Gregory Cherlin and Boris Zilber, that all simple groups of finite Morley rank are simple algebraic groups. Towards this end, the development of the theory of groups of finite Morley rank has achieved a good theory of Sylow 2-subgroups. It is now common practice to divide the Cherlin-Zilber conjecture into different cases depending on the nature of the...

متن کامل

Asymmetric Rectangular Waveform in Stimulation with High Frequency Alternating Current Reduces the Threshold for Neural Conduction Block

Introduction Abnormal neural impulses in the nervous system may lead to various diseases and disabilities. High frequency alternating currents (HFAC) has been used to block the propagation of such impulses and improve the symptoms or disabilities. The technique is safe, reversible, and relatively selective, and its reliability, the optimum stimulation parameters, and elimination of the onset re...

متن کامل

Algebraic Properties of Intuitionistic Fuzzy Residuated Lattices

In this paper, we investigate more relations between the symmetric residuated lattices $L$ with their corresponding intuitionistic fuzzy residuated lattice $tilde{L}$. It is shown that some algebraic structures of $L$ such as Heyting algebra, Glivenko residuated lattice and strict residuated lattice are preserved for $tilde{L}$. Examples are given for those structures that do not remain the sam...

متن کامل

Labelling the character tables of symmetric and alternating groups

Let X be a character table of the symmetric group Sn. It is shown that unless n = 4 or n = 6, there is a unique way to assign partitions of n to the rows and columns of X so that for all λ and ν, Xλν is equal to χ(ν), the value of the irreducible character of Sn labelled by λ on elements of cycle type ν. Analogous results are proved for alternating groups, and for the Brauer character tables of...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 2012