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991.
992.
993.
AbstractWe previously classified three-dimensional zeropotent algebras over an algebraically closed field of any characteristic except for two. The exceptional case of characteristic two is special because some of the previous transformation matrices to verify isomorphism are unavailable. In this paper, we give new transformation matrices peculiar to characteristic two and then achieve classification in the exceptional case. We thus accomplish a classification of three-dimensional zeropotent algebras over an algebraically closed field of any characteristic. 相似文献
994.
AbstractIt is shown that a finite-dimensional formally real simple Jordan algebra is completely determined by the relation of Jordan-orthogonality.Communicated by Prof. Alberto Elduque 相似文献
995.
设α是可数离散群G和H的半直积G■_σH在冯·诺依曼代数M上的作用,则β_h=α_((e,h))AdU_h定义了群H在冯·诺依曼代数交叉积M■_αG上的作用β.本文证明了交叉积冯·诺依曼代数M■_α(G■_σH)与(M■_αG)■_βH是*-同构的,因此在一定条件下,冯·诺依曼代数的交叉积满足结合律. 相似文献
996.
Ali Ghaffari 《数学学报(英文版)》2008,24(7):1089-1096
In this paper, among other things, the author studies the weak^*-closed left translation invariant complemented subspace of semigroup algebras and group algebras. Also, the author studies the relationships between projections and amenability. 相似文献
997.
998.
We characterize the surjective additive maps compressing the spectral function Δ(·) between standard operator algebras acting on complex Banach spaces, where Δ(·) stands for any one of nine spectral functions σ(·), σl(·), σr(·),σl(·) ∩ σr(·), δσ(·), ησ(·), σap(·), σs(·), and σap(·) ∩ σs(·). 相似文献
999.
Liaqat Ali Khan 《Journal of Mathematical Analysis and Applications》2008,343(1):141-150
In this paper, we consider the notion of module homomorphisms in the general topological module setting and establish their linearity and continuity under some suitable conditions. We also introduce the strict and uniform topologies on the modules of continuous linear homomorphisms and study their various properties. 相似文献
1000.
Ali Ghaffari 《Semigroup Forum》2008,76(1):95-106
Let S be a foundation locally compact topological semigroup. Two new topologies τ
c
and τ
w
are introduced on M
a
(S)*. We introduce τ
c
and τ
w
almost periodic functionals in M
a
(S)*. We study these classes and compare them with each other and with the norm almost periodic and weakly almost periodic functionals.
For f∈M
a
(S)*, it is proved that T
f
∈ℬ(M
a
(S),M
a
(S)*) is strong almost periodic if and only if f is τ
c
-almost periodic. Indeed, we have obtained a generalization of a well known result of Crombez for locally compact group to
a more general setting of foundation topological semigroups. Finally if P(S) (the set of all probability measures in M
a
(S)) has the semiright invariant isometry property, it is shown that the set of τ
w
-almost periodic functionals has a topological left invariant mean. 相似文献