设A和B是无限维Banach空间X上的准算子代数且ψ:A→B是一个保单位的线性双射。证明了如果对任意的A,B∈A且AB=0,有ψ(A。B)=ψ(A)。ψ(B)成立,则对任意A,B∈A,要么ψ(AB)=ψ(A)ψ(B),要么ψ(AB)=ψ(B)ψ(A)。
Let A and B be standard operator algebras on an infinite dimensional Banach space X and ψ: A →B be a preserve unit linear bijection. We prove that if ψ(A oB) =ψ(A) o ψ(B) holds for all A,B ∈ ,A with AB =0, then for all A,B ∈Aeither ψ(AB) =ψ(A)ψ(B) or ψ(AB) =ψ(B)ψ(A) holds.