The stability radius of a quasi-Fredholm operator
نویسندگان
چکیده
منابع مشابه
The Stability Radius of Fredholm Linear Pencils
Let T and S be two bounded linear operators from Banach spaces X into Y and suppose that T is Fredholm and dimN(T − λS) is constant in a neighborhood of λ = 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 is a consequence of more general results due to H. Bart and D.C. Lay (1980) that d(T ;S) = limn→∞ γn(T ;S) , wher...
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ژورنال
عنوان ژورنال: Proceedings of the American Mathematical Society
سال: 1998
ISSN: 0002-9939,1088-6826
DOI: 10.1090/s0002-9939-98-04253-1