一类拟相似算子的本质谱

Essential Spectrum of Quasisimilar Operators

引进亚控制算子的概念,通过算子谱的精密结构的分析,给出拟相似亚控制算子的本质谱相等的若干条件,所得结果改进和发展了Williams L R的有关结果.

Introducing the concept of hypo-dominant operators, by means of the analysis of the precise constitution of spectrum of operators, this paper gives some conditions for equality of essential spectrum of two quasisimilar hypo-dominant operators, these results improves and generalizes the results of L. R. Williams.