Operational quantities characterizing semi-Fredholm operators

Manuel González; Antonio Martinón

Studia Mathematica (1995)

  • Volume: 114, Issue: 1, page 13-27
  • ISSN: 0039-3223

Abstract

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Several operational quantities have appeared in the literature characterizing upper semi-Fredholm operators. Here we show that these quantities can be divided into three classes, in such a way that two of them are equivalent if they belong to the same class, and are comparable and not equivalent if they belong to different classes. Moreover, we give a similar classification for operational quantities characterizing lower semi-Fredholm operators.

How to cite

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González, Manuel, and Martinón, Antonio. "Operational quantities characterizing semi-Fredholm operators." Studia Mathematica 114.1 (1995): 13-27. <http://eudml.org/doc/216176>.

@article{González1995,
abstract = {Several operational quantities have appeared in the literature characterizing upper semi-Fredholm operators. Here we show that these quantities can be divided into three classes, in such a way that two of them are equivalent if they belong to the same class, and are comparable and not equivalent if they belong to different classes. Moreover, we give a similar classification for operational quantities characterizing lower semi-Fredholm operators.},
author = {González, Manuel, Martinón, Antonio},
journal = {Studia Mathematica},
keywords = {operational quantity; semi-Fredholm operator; upper semi-Fredholm operators; lower semi-Fredholm operators},
language = {eng},
number = {1},
pages = {13-27},
title = {Operational quantities characterizing semi-Fredholm operators},
url = {http://eudml.org/doc/216176},
volume = {114},
year = {1995},
}

TY - JOUR
AU - González, Manuel
AU - Martinón, Antonio
TI - Operational quantities characterizing semi-Fredholm operators
JO - Studia Mathematica
PY - 1995
VL - 114
IS - 1
SP - 13
EP - 27
AB - Several operational quantities have appeared in the literature characterizing upper semi-Fredholm operators. Here we show that these quantities can be divided into three classes, in such a way that two of them are equivalent if they belong to the same class, and are comparable and not equivalent if they belong to different classes. Moreover, we give a similar classification for operational quantities characterizing lower semi-Fredholm operators.
LA - eng
KW - operational quantity; semi-Fredholm operator; upper semi-Fredholm operators; lower semi-Fredholm operators
UR - http://eudml.org/doc/216176
ER -

References

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  19. [19] J. Zemánek, Geometric characteristics of semi-Fredholm operators and their asymptotic behaviour, Studia Math. 80 (1984), 219-234. Zbl0556.47008
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