Embeddings ofU 3(8),Sz(8) and the Rudvalis group in algebraic groups of typeE 7

Oblatum 5-XII-1991 & 24-II-1993     

GF（2）—modules for Sz（q）wrCt

LetVbeavectorspaceoverfieldK=GF(q),whereq=2",nodd.ThethereexistsinGL(V)somesubgroupH,whichisisomorphictoSz(q),andtheactionofHonVderivessomeirreduciblemodulestructureforH-LetF=GF(2),thenVcanbeseenasanFH-mod-ule,Vremainsirreducible,andVissaidtobeanaturalFH-module.Thenotionofnaturalmodule'forSz(q)canbegeneralizedtothewrethproductSz(q)wed(thedefinitionforthewreathproduct,seeLlj'9'l9),Thenotationsandterminol-ogyinthispaper'exceptforfewexceptions,areeitherstandardoeasiluaccessiblefromL2j'…     

Two maximal subgroups of E8(2)

We show that E₈(2) has a unique conjugacy class of subgroups isomorphic to PSp₄(5) and a unique conjugacy class of subgroups isomorphic to PSL₃(5). There normalizers are maximal subgroups of E₈(2) and are, respectively, isomorphic to PGSp₄(5) and Aut(PSL₃(5)).     

Embeddings of the groupL(2,13) in groups of lie typeE 6

In this paper we show there is exactly one conjugacy class of subgroups ofE ₆(ℂ) isomorphic toL(2, 13) with each of the characters 13+14 and 1+12+14 on a 27-dimensional module forE ₆. The one with character 13+14 is a subgroup of the irreducible closed subgroup of typeG ₂. There is a unique conjugacy class for each of the three algebraic conjugate characters 1+12+14. Our arguments have applications to fields of characteristic prime to |L(2, 13)|. Dedicated to John Thompson for his keen interest in broad areas of mathematics and in mathematicians     

Embeddings and hyperplanes of the Lie incidence geometry of type E7,1

This paper continues a program to show that for most of the standard Lie incidence geometries, all geometric hyperplanes arise from a necessarily absolutely universal embedding, by addingE _7,1 to the list. It follows from [5, 12] that any projective embedding of this point line geometry is a homomorphic image of the one afforded by the 56-dimensional module for the groupE ₇(K).This work was supported by a grant from the National Science Foundation.     

Embeddings of Un(q2) and symmetric strongly regular graphs

In the geometric setting of the embedding of the unitary group U_n(q²) inside an orthogonal or a symplectic group over the subfield GF(q) of GF(q²), q odd, we show the existence of infinite families of transitive two‐character sets with respect to hyperplanes that in turn define new symmetric strongly regular graphs and two‐weight codes. © 2009 Wiley Periodicals, Inc. J Combin Designs 18: 248–253, 2010     

Suzuki群Sz(q)与2-(v,k,1)区组设计

§ 1　IntroductionA2 -( v,k,1 ) design D=( Ω,B) is a system consisting of a finite setΩ ofv points anda collection Bofk-subsets ofΩ ,called blocks,such thatany 2 -subsetofΩ is contained inexactly one block.We shall always assume that2 相似文献   

The Suzuki Groups Sz(q) and 2-(v,k,1) Designs

A 2-(v,k,1) design D=(Ω, B) is a systemconsisting of a finite set Ω of vpoints and a collection B of k-subsets of Ω, calledblocks,such that any 2-subset of Ω is contained in exactly one block.We shall always assume that 2相似文献   

The Suzuki Groups Sz(q)and 2-(v, k, 1) Designs

A 2-(v,k, l) design D=(Ω,B) is a system consisting of a finite set Ω of v points and acollection B of k-subsets of Ω, called blocks, such that any 2-subset of Ω is contained in exactlyone bled. We shall always assume that 2 < k < v.Let G S AutD be a group of automorphisms of a 2-(v, k, 1) design D. G is said to be blocktransitive (block primitive) on D if G is transitive (primitive, respectively) on B. G is said tobe point transitive (point primitive) on D if G is transitive (primiti…     

SUZUKI GROUPS Sz（q） AND 2-（v,k, 1） BLOCK DESIGNS

It is proved that if D be a 2-(v,k,1) design with G≤Aut D block primitive then G does not have a Suzuki group Sz(q) as the socle.     

一个关于球面和环面上嵌入图的近-三角剖分嵌入的内插定理(I)

一个近-三角剖分嵌入是指一个曲面上的嵌入图使得几乎所有的面都是三角形,至多只有一个可能的例外.文中作者证明了如下结论:如果一个图G 在球面S₀(或环面S₁)上有近-三角剖分嵌入,那么G在每一个可定向曲面S_k有近-三角剖分嵌入,其中k=h,h+1,\cdots ,\lfloor\frac{\beta(G)}{2}\rfloor$, 而h=0(或1)并且β(G)是图G的Betti数.特别地,G是上可嵌入的.     

Embeddings of Sλ(2, 4, v)

It is shown that the necessary condition for a given S_λ(2,4,u) to be embedded in some S_λ(2,4,v) as a subdesign, namely v ≥ 3u + 1, is also sufficient for the case of λ = 6. Combining this with the previously known results gives the same sufficiency for any positive integer λ. © 1994 John Wiley & Sons, Inc.     

Embeddings ofC(Δ) andL 1[0, 1] in Banach lattices

It is proved that ifE is a separable Banach lattice withE′ weakly sequentially complete,F is a Banach space andT:E→F is a bounded linear operator withT′F′ non-separable, then there is a subspaceG ofE, isomorphic toC(Δ), such thatT _G is an isomorphism, whereC(Δ) denotes the space of continuous real valued functions on the Cantor discontinuum. This generalizes an earlier result of the second-named author. A number of conditions are proved equivalent for a Banach latticeE to contain a subspace order isomorphic toC(Δ). Among them are the following:L ¹ is lattice isomorphic to a sublattice ofE′;C(Δ)′ is lattice isomorphic to a sublattice ofE′; E contains an order bounded sequence with no weak Cauchy subsequence;E has a separable closed sublatticeF such thatF′ does not have a weak order unit. The research of both authors was partially supported by the National Science Foundation, NSF Grant No MPS 71-02839 A04.