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BY-NC-ND 3.0 license Open Access Published by De Gruyter December 12, 2009

Translatable radii of an operator in the direction of another operator II

  • Kallol Paul EMAIL logo
From the journal Mathematica Slovaca

Abstract

One of the couple of translatable radii of an operator in the direction of another operator introduced in earlier work [PAUL, K.: Translatable radii of an operator in the direction of another operator, Scientae Mathematicae 2 (1999), 119–122] is studied in details. A necessary and sufficient condition for a unit vector f to be a stationary vector of the generalized eigenvalue problem Tf = λAf is obtained. Finally a theorem of Williams ([WILLIAMS, J. P.: Finite operators, Proc. Amer. Math. Soc. 26 (1970), 129–136]) is generalized to obtain a translatable radius of an operator in the direction of another operator.

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Published Online: 2009-12-12
Published in Print: 2010-2-1

© 2010 Mathematical Institute, Slovak Academy of Sciences

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

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