根据值域的稠密性和闭性,可将有界线性算子的点谱和剩余谱进一步细分为1,2-类点谱和1,2-类剩余谱.针对3×3阶上三角算子矩阵,采用分析方法和空间分解方法分别刻画了可能1,2-类点谱和可能1,2-类剩余谱.
According to the denseness and closedness of range of an operator, its point spectrum and residual spectrum are split into 1, 2-point-spectrum and 1, 2-residualspectrum, respectively. For 3 ×3 upper triangular operator matrices, the possible point spectra and possible residual spectra, ∪D D,E,F σ*,i( MD,E,F ) (* =p, r; i : 1, 2), are given by means of the analysis method and block operator technique,