一类无界算子矩阵的本质谱
THE ESSENTIAL SPECTRUM OF SOME UNBOUNDED BLOCK OPERATOR MATRICES

本文研究了次对角占优的无界算子矩阵M=（CADB）的左本质谱和本质谱.利用分析方法和分块算子的性质，得到了整个算子矩阵的本质谱（左本质谱）与其内部元素的本质谱（左本质谱）之间的关系.
In this paper, we consider the left essential spectrum and essential spectrum of off-diagonally dominant unbounded block operator matrices M=(CADB). By means of analysis method and basic properties of operator matrices, we obtain the relationship between the essential spectrum and essential spectrum of block operator matrices with their entries