Operators with disconnected spectra are dense
نویسندگان
چکیده
منابع مشابه
Truncation method for operators with disconnected essential spectrum
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[1.0.2] Remark: The same argument applied to T shows that σ(T) is inside the closed ball of radius |T|op. By the elementary identity T − λ = (T − λ) · (Tn−1 + Tn−2λ+ . . .+ Tλn−2 + λn−2) (T − λ)−1 exists for |λ| > |T|op, that is, for |λ| > |Tn| op . That is, σ(T ) is inside the closed ball of radius infn≥1 |Tn| op . The latter expression is the spectral radius of T . This notion is relevant to ...
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ژورنال
عنوان ژورنال: Bulletin of the American Mathematical Society
سال: 1972
ISSN: 0002-9904
DOI: 10.1090/s0002-9904-1972-12981-1