摘要
称有界线性算子T∈L(X)满足性质(gz),如果T的上半B-Weyl谱在T的谱集中的补集恰好为T的逼近点谱中孤立的特征值全体.本文首先讨论了性质(gz)与其它广义Weyl型定理之间的关系;然后利用新定义的谱集σ_2(T)与Drazin谱之间的关系,给出了Banach空间中有界线性算子T及其函数演算满足性质(gz)的等价刻画;最后利用所得结论讨论了弱-H(P)类算子的性质(gz).
A bounded linear operator T ∈ L(X) defined on a Banach space X satisfies property(gz), if the complement in the spectrum σ(T) of the upper semi-B-Weyl spectrumσ_(SBF)~-_+(T) is the set of all isolated points of the approximate point spectrum σ_a(T) which are eigenvalues. In this note, we first study the conditions between property(gz) and other generalized Weyl-type theorem, then establish for a bounded linear operator and the calculus defined on a Banach space the sufficient and necessary conditions for which property(gz)holds by means of the condition between the new spectrum σ_2(T) and the Drazin spectrum.In addition, using the main result, property(gz) of the class of weak-H(P) is considered.
引文
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