Premium
Certain Norm Related Quantities of Unbounded Linear Operators
Author(s) -
Labuschagne L. E.
Publication year - 1992
Publication title -
mathematische nachrichten
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.913
H-Index - 50
eISSN - 1522-2616
pISSN - 0025-584X
DOI - 10.1002/mana.19921570111
Subject(s) - mathematics , operator norm , linear operators , operator theory , norm (philosophy) , dual norm , continuous linear operator , pure mathematics , normed vector space , algebra over a field , mathematical analysis , political science , law , bounded function
Certain norm related functions of linear operators are considered in the very general setting of not necessarily continuous linear operators in normed spaces. These are shown to be closely related to the theory of precompact, strictly cosingular and a class of Φ − type operators in addition to having applications to perturbation theory. We also obtain some basic continuity and precompactness properties of linear operators in normed spaces which are expressed in terms of the functions under consideration.