摘要
本文研究了Hilbert C~*-模上可共轭算子的并联和,推广了矩阵和Hilbert空间上有界线性算子的一些相关结果.通过举例说明:存在一个Hilbert C~*-模H,以及H上的两个可共轭的正算子A和B,使得算子方程A~(1/2)=(A+B)~(1/2)X, X∈■(H)无解,其中■(H)为H上的可共轭算子全体.
The parallel sum for adjointable operators on Hilbert C~*-modules is introduced and studied.Some results known for matrices and bounded linear operators on Hilbert spaces are generalized to the case of adjointable operators on Hilbert C*-modules.It is shown that there exist a Hilbert C~*-module H and two positive operators A,B ∈■(H)such that the operator equation A~(1/2) =(A+B)~(1/2)X,X∈■(H)has no solution,where ■(H)denotes the set of all adjointable operators on H.
引文
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