The stability radius of an operator of Saphar type

Christoph Schmoeger

Studia Mathematica (1995)

  • Volume: 113, Issue: 2, page 169-175
  • ISSN: 0039-3223

Abstract

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A bounded linear operator T on a complex Banach space X is called an operator of Saphar type if its kernel is contained in its generalized range ⋂ n = 1 ∞ T n ( X ) and T is relatively regular. For T of Saphar type we determine the supremum of all positive numbers δ such that T - λI is of Saphar type for |λ| < δ.

How to cite

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Schmoeger, Christoph. "The stability radius of an operator of Saphar type." Studia Mathematica 113.2 (1995): 169-175. <http://eudml.org/doc/216167>.

@article{Schmoeger1995,
abstract = {A bounded linear operator T on a complex Banach space X is called an operator of Saphar type if its kernel is contained in its generalized range $⋂_\{n=1\}^\{∞\} T^n(X)$ and T is relatively regular. For T of Saphar type we determine the supremum of all positive numbers δ such that T - λI is of Saphar type for |λ| < δ.},
author = {Schmoeger, Christoph},
journal = {Studia Mathematica},
keywords = {operator of Saphar type; kernel},
language = {eng},
number = {2},
pages = {169-175},
title = {The stability radius of an operator of Saphar type},
url = {http://eudml.org/doc/216167},
volume = {113},
year = {1995},
}

TY - JOUR
AU - Schmoeger, Christoph
TI - The stability radius of an operator of Saphar type
JO - Studia Mathematica
PY - 1995
VL - 113
IS - 2
SP - 169
EP - 175
AB - A bounded linear operator T on a complex Banach space X is called an operator of Saphar type if its kernel is contained in its generalized range $⋂_{n=1}^{∞} T^n(X)$ and T is relatively regular. For T of Saphar type we determine the supremum of all positive numbers δ such that T - λI is of Saphar type for |λ| < δ.
LA - eng
KW - operator of Saphar type; kernel
UR - http://eudml.org/doc/216167
ER -

References

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  15. [15] J. Zemánek, The reduced minimum modulus and the spectrum, ibid. 12 (1989), 449-454. Zbl0674.47002

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