三角矩阵代数上的保交换可加映射

本文研究了三角矩阵代数上保持交换性的可加映射的结构.利用最近Marcoux与Sourour发表在[Linear Alg.Appl.288(1999),89-104]上的一个结果,我们证明了任意域F上的三角矩阵代数Tn(F)(n＞2)上的可加满射ψ双向保交换当且仅当ψ是Tn(F)上一个可加泛函与Tn(F)上某个环自同构或环反自同构之和.     

关于域上上三角矩阵的诱导映射

令F是一个域,T_n(F)是F上所有n×n上三角矩阵的集合.本文分别给出了矩阵保相似性及保交换性的定义,并使用矩阵技术和初等方法,得到了T_n(F)的保相似性及保交换性的诱导映射的一般形式,并且给出了例子,来解释一些结果之间的关系.     

交换半环上三角矩阵代数的自同构

证明了如果尺是含有恒等元的交换半环，那么R上的n阶上三角矩阵代数的自同构都是内自同构．     

上三角矩阵的线性交换映射的表示

设Trn(R)表示定义在实数域R上的n×n阶上三角矩阵的集合,φ是定义Trn(R)上线性映射.如果对任意X∈Trn(R)有Xφ(X)=φ(X)X成立,称φ是线性交换映射.本文利用初等的矩阵计算方法描述了当φ(I)=I时,线性交换映射φ的表示形式,而且给出了φ的Frobenius范数‖φ(X)‖F的估计.     

交换半环上三角矩阵代数的Jordan同构

探讨交换半环上的上三角矩阵代数的Jordan同构.证明如果R是一个交换半环且R中仅有幂等元0与1,那么从R上的上三角矩阵代数Tn(R)到R上的任意代数的每一个Jordan同构要么是一个同构要么是一个反同构.     

三角代数上的交换零点Jordan可导映射

给出了三角代数上交换零点Jordan可导映射的结构.作为应用,得到了套代数上交换零点Jordan可导映射的具体形式.     

交换环上上三角矩阵代数在全矩阵代数中的扩代数及其若当导子

设R是任意含么交换环,2是R的可逆元.M(n,R)表示R上所有n×n级矩阵形成的代数,T(n,R)表示R上所有n×n级上三角矩阵形成的代数.决定了T(n,R)在M(n,R)中的扩代数,并具体刻画了这些扩代数的若当导子.     

三角代数上的交换零点ξ-Lie可导映射

设u是数域F上的一个三角代数,δ是u上的一个线性映射,ξ∈F且ξ≠1证明了:如果对任意的x,y∈u且xy=yx=0有δ([x,y]_ξ)=[δ(x),y]_ξ+[x,δ(y)]_ξ,则在u上存在一个导子Φ和一个中心元λ使得对任意的x∈u,有δ(x)=Φ(x)+λx.     

交换环上的严格上三角代数上的双导子

Let Nn（R）be the algebra consisting of all strictly upper triangular n × n matrices over a commutative ring R with the identity.An R-bilinear map φ ：Nn（R）×Nn（R）→ Nn（R）is called a biderivation if it is a derivation with respect to both arguments.In this paper,we define the notions of central biderivation and extremal biderivation of Nn（R）,and prove that any biderivation of Nn（R）can be decomposed as a sum of an inner biderivation,central biderivation and extremal biderivation for n ≥ 5.     

On classical adjoint-commuting mappings between matrix algebras

Let F be a field and let m and n be integers with m,n?3. Let M_n denote the algebra of n×n matrices over F. In this note, we characterize mappings ψ:M_n→M_m that satisfy one of the following conditions:

1.

|F|=2 or |F|>n+1, and ψ(adj(A+αB))=adj(ψ(A)+αψ(B)) for all A,B∈M_n and α∈F with ψ(I_n)≠0.

2.

ψ is surjective and ψ(adj(A-B))=adj(ψ(A)-ψ(B)) for every A,B∈M_n.

Here, adjA denotes the classical adjoint of the matrix A, and I_n is the identity matrix of order n. We give examples showing the indispensability of the assumption ψ(I_n)≠0 in our results.     

(Strongly) Gorenstein injective modules over upper triangular matrix Artin algebras

Let \(\Lambda = \left( {\begin{array}{*{20}{c}} A&M \\ 0&B \end{array}} \right)\) be an Artin algebra. In view of the characterization of finitely generated Gorenstein injective Λ-modules under the condition that M is a cocompatible (A,B)-bimodule, we establish a recollement of the stable category \(\overline {Ginj\left( \Lambda \right)} \). We also determine all strongly complete injective resolutions and all strongly Gorenstein injective modules over Λ.     

Involutions for upper triangular matrix algebras

In this paper we describe completely the involutions of the first kind of the algebra UT_n(F) of n×n upper triangular matrices. Every such involution can be extended uniquely to an involution on the full matrix algebra. We describe the equivalence classes of involutions on the upper triangular matrices. There are two distinct classes for UT_n(F) when n is even and a single class in the odd case.Furthermore we consider the algebra UT₂(F) of the 2×2 upper triangular matrices over an infinite field F of characteristic different from 2. For every involution *, we describe the *-polynomial identities for this algebra. We exhibit bases of the corresponding ideals of identities with involution, and compute the Hilbert (or Poincaré) series and the codimension sequences of the respective relatively free algebras.Then we consider the *-polynomial identities for the algebra UT₃(F) over a field of characteristic zero. We describe a finite generating set of the ideal of *-identities for this algebra. These generators are quite a few, and their degrees are relatively large. It seems to us that the problem of describing the *-identities for the algebra UT_n(F) of the n×n upper triangular matrices may be much more complicated than in the case of ordinary polynomial identities.     

Polynomial functions on upper triangular matrix algebras

There are two kinds of polynomial functions on matrix algebras over commutative rings: those induced by polynomials with coefficients in the algebra itself and those induced by polynomials with scalar coefficients. In the case of algebras of upper triangular matrices over a commutative ring, we characterize the former in terms of the latter (which are easier to handle because of substitution homomorphism). We conclude that the set of integer-valued polynomials with matrix coefficients on an algebra of upper triangular matrices is a ring, and that the set of null-polynomials with matrix coefficients on an algebra of upper triangular matrices is an ideal.     

Derived equivalences between triangular matrix algebras

In this paper, we study derived equivalences between triangular matrix algebras using certain classical recollements. We show that special properties of these recollements actually characterize triangular matrix algebras and describe methods to construct tilting modules and tilting complexes inducing derived equivalences between them.     

On injective Jordan semi-triple maps of matrix algebras

We show that every injective Jordan semi-triple map on the algebra M_n(F) of all n × n matrices with entries in a field F (i.e. a map Φ:M_n(F)→M_n(F) satisfying

Φ(ABA)=Φ(A)Φ(B)Φ(A)     

Ternary mappings of triangular algebras

Aequationes mathematicae - We take a categorical approach to describe ternary derivations and ternary automorphisms of triangular algebras. New classes of automorphisms and derivations of...     

Similarity preserving linear maps on upper triangular matrix algebras

In this note we consider similarity preserving linear maps on the algebra of all n × n complex upper triangular matrices T_n. We give characterizations of similarity invariant subspaces in T_n and similarity preserving linear injections on T_n. Furthermore, we considered linear injections on T_n preserving similarity in M_n as well.     

Lattice-ordered triangular matrix algebras

In this article we give some necessary and sufficient conditions for a lattice-ordered semigroup algebra to be isomorphic to a lattice-ordered triangular matrix algebra.