Let D be a 2-(v, k, 4) symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut(X) where X ≌ PSL2(q).Then D is a 2-(15,8,4) symmetric design with X = PSL2(9) and ...Let D be a 2-(v, k, 4) symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut(X) where X ≌ PSL2(q).Then D is a 2-(15,8,4) symmetric design with X = PSL2(9) and Xx = PGL2(3) where x is a point of D.展开更多
In this paper,we give transcendence bases of the rational invariants fields of the generalized classical groups and their subgroups B,N and T,and we also compute the orders of them.Furthermore,we give explicit generat...In this paper,we give transcendence bases of the rational invariants fields of the generalized classical groups and their subgroups B,N and T,and we also compute the orders of them.Furthermore,we give explicit generators for the rational invariants fields of the Borel subgroup and the Neron-Severi subgroup of the general linear group.展开更多
Let G be a classical group over an arbitrary field F,acting on an n-dimensional vector space V=V(n,F)over a field F.In this paper,we classify the maximal subgroups of G,which normalizes a solvable subgroup N of GL(L,F...Let G be a classical group over an arbitrary field F,acting on an n-dimensional vector space V=V(n,F)over a field F.In this paper,we classify the maximal subgroups of G,which normalizes a solvable subgroup N of GL(L,F)not lying in F^(*)1_(V).展开更多
Let G be a classical group over an arbitrary field F,acting on an n-dimensional F-space V=V(n,F).All those maximal subgroups of G are classified each of which normalizes a solvable subgroup N of GL(V/F)not lying in F^...Let G be a classical group over an arbitrary field F,acting on an n-dimensional F-space V=V(n,F).All those maximal subgroups of G are classified each of which normalizes a solvable subgroup N of GL(V/F)not lying in F^(*)1v.展开更多
This is the second part of a pedagogical introduction to the theory of buildings of Jacques Tits.We de ne a(B,N)pair and construct a building out of it.Then we give a description of Chevalley groups,their(B,N)pair and...This is the second part of a pedagogical introduction to the theory of buildings of Jacques Tits.We de ne a(B,N)pair and construct a building out of it.Then we give a description of Chevalley groups,their(B,N)pair and the associated buildings.We illustrates this theory with many examples from classical groups.展开更多
Let F_(q)be a finite field of any characteristic and GL(n,F_(q))be the general linear group over F_(q).Suppose W denotes the standard representation of GL(n,F_(q)),and GL(n,F_(q))acts diagonally on the direct sum of W...Let F_(q)be a finite field of any characteristic and GL(n,F_(q))be the general linear group over F_(q).Suppose W denotes the standard representation of GL(n,F_(q)),and GL(n,F_(q))acts diagonally on the direct sum of W and its dual space W^(∗).Let G be any subgroup of GL(n,F_(q)).Suppose the invariant field F_(q)(W)G=F_(q)(f1,f2,…,fk),where f1,f2,…,fk in F_(q)[W]G are homogeneous invariant polynomials.We prove that there exist homogeneous polynomialsl1,l2,…,ln in the invariant ring F_(q)[W⊕W^(∗)]G such that the invariant field F_(q)(W⊕W^(∗))G is generated by{f1,f2,…,fk,l1,l2,…,ln}over F_(q).展开更多
基金Supported by the National Natural Science Foundation of China(11071081)
文摘Let D be a 2-(v, k, 4) symmetric design and G be a flag-transitive point-primitive automorphism group of D with X ≥G ≤Aut(X) where X ≌ PSL2(q).Then D is a 2-(15,8,4) symmetric design with X = PSL2(9) and Xx = PGL2(3) where x is a point of D.
文摘In this paper,we give transcendence bases of the rational invariants fields of the generalized classical groups and their subgroups B,N and T,and we also compute the orders of them.Furthermore,we give explicit generators for the rational invariants fields of the Borel subgroup and the Neron-Severi subgroup of the general linear group.
文摘Let G be a classical group over an arbitrary field F,acting on an n-dimensional vector space V=V(n,F)over a field F.In this paper,we classify the maximal subgroups of G,which normalizes a solvable subgroup N of GL(L,F)not lying in F^(*)1_(V).
基金funded by Scientific Research Project of Beijing Educational Committee(No.KM202110028004).
文摘Let G be a classical group over an arbitrary field F,acting on an n-dimensional F-space V=V(n,F).All those maximal subgroups of G are classified each of which normalizes a solvable subgroup N of GL(V/F)not lying in F^(*)1v.
文摘This is the second part of a pedagogical introduction to the theory of buildings of Jacques Tits.We de ne a(B,N)pair and construct a building out of it.Then we give a description of Chevalley groups,their(B,N)pair and the associated buildings.We illustrates this theory with many examples from classical groups.
基金This research was partially supported by the NNSF of China(No.11301061).
文摘Let F_(q)be a finite field of any characteristic and GL(n,F_(q))be the general linear group over F_(q).Suppose W denotes the standard representation of GL(n,F_(q)),and GL(n,F_(q))acts diagonally on the direct sum of W and its dual space W^(∗).Let G be any subgroup of GL(n,F_(q)).Suppose the invariant field F_(q)(W)G=F_(q)(f1,f2,…,fk),where f1,f2,…,fk in F_(q)[W]G are homogeneous invariant polynomials.We prove that there exist homogeneous polynomialsl1,l2,…,ln in the invariant ring F_(q)[W⊕W^(∗)]G such that the invariant field F_(q)(W⊕W^(∗))G is generated by{f1,f2,…,fk,l1,l2,…,ln}over F_(q).