Essential numerical ranges for linear operator pencils
نویسندگان
چکیده
منابع مشابه
The Stability Radius of Linear Operator Pencils
Let T and S be two bounded linear operators from Banach spaces X into Y and suppose that T is Fredholm and the stability number k(T ;S) is 0. Let d(T ;S) be the supremum of all r > 0 such that dimN(T − λS) and codim R(T − λS) are constant for all λ with |λ| < r. It was proved in 1980 by H. Bart and D.C. Lay that d(T ;S) = limn→∞ γn(T ;S) , where γn(T ;S) are some non-negative (extended) real nu...
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ژورنال
عنوان ژورنال: IMA Journal of Numerical Analysis
سال: 2019
ISSN: 0272-4979,1464-3642
DOI: 10.1093/imanum/drz049