POSITIVITY AND STRICT CONTRACTIVITY OF FUNCTIONS OF OPERATORS

Authors
GURVITS L RODMAN L
Citation
L. Gurvits et L. Rodman, POSITIVITY AND STRICT CONTRACTIVITY OF FUNCTIONS OF OPERATORS, Integral equations and operator theory, 28(1), 1997, pp. 17-27
Citations number
9
Categorie Soggetti
Mathematics, Pure",Mathematics,Mathematics
Journal title
Integral equations and operator theory → ACNP
ISSN journal
0378620X
Volume
28
Issue
1
Year of publication
1997
Pages
17 - 27
Database
ISI
SICI code
0378-620X(1997)28:1<17:PASCOF>2.0.ZU;2-H
Abstract
Caratheodory class functions f(z) are described having the property th at the selfadjoint part of f(A) is positive definite for every contrac tion A whose spectral radius is less than 1. Analogous results are obt ained for bounded analytic functions in the unit disc, and for the Nev anlinna class. Applications to Markov chains are indicated.