设H为复的无限维可分Hilbert空间,B(H)为H上有界线性算子的全体.若σ(T)/σw(T)=πoo(T),则称T∈B(H)满足Weyl定理,其中σ(T)和σw(T)分别表示算子T的谱和Weyl谱,πroo(T)={λ∈isoσ(T):0〈dimN(T一入Ⅰ)〈∞};当δ(T)\δw(T)Cπoo(T)时,称T∈B(H)满足Browder定理.本文利用算子的广义Kato分解性质,刻画了算子在微小紧摄动下单值延拓性质(SVEP)与Weyl型定理之间的关系.
Let H be an infinite dimensional separable complex Hilbert space and B(H) be the algebra of all bounded linear operators on H. T E B(H) satisfies Weyl's theorem if o-(T)/o%(T) ---- zr00(T), where (T) and σw(T) denote the spectrum and the Weyl spectrum of T respectively, zr00(T) = {A 6 isoa(T) : 0 〈dimN(T- AI) 〈 ∞}. If σ(T)/σω(T)∈πroo(T), T is called satisfying Browder's theorem. In this paper, using the property of generalized Kato decomposition, we explore the relation between the single-valued extension property and Weyl's theorem under small compact perturbations.