上三角算子矩阵的Kato本质谱摄动

On the perturbation of the Kato essential spectra for upper triangular operator matrices

令σek(T)=σe(T)∪σk(T)为算子T的Kato本质谱,其中σe(T)和σk(T)分别表示算子T的本质谱以及Kato谱。研究了Hilbert空间H⊙K上的上三角算子矩阵MC=[0ACB]的Kato本质谱摄动。

Let σek（T）=σe（T）∪σk（T） be the Kato essential spectra for bounded linear operator T,where σe（T） and σk（T） denote the Kato spectrum and essential spectrum for T respectively.The perturbations of the Kato essential for an upper triangular operator matrices such as MC=[AC0B] acting on a Hilbert space H⊙K are studied.