AbstractAn analogue of Krein's extension theorem is proved for operator-valued positive definite functions on free groups. The proof gives also the parametrization of all extensions by means of a generalized type of Szegö parameters. One singles out a distinguished completion, called central, which is related to quasi-multiplicative positive definite functions. An application is given to factorization of noncommutative polynomials
In this paper we give an analogue of Krein’s formula on the description of generalized resolvents of...
AbstractIt is proved that if a group of unitary operators and a local semigroup of isometries satisf...
This article studies the properties of positive definite, radial functions on free groups following ...
AbstractAn analogue of Krein's extension theorem is proved for operator-valued positive definite fun...
AbstractLet Ω be a locally compact abelian ordered group. We say that Ω has the extension property i...
This monograph deals with the mathematics of extending given partial data-sets obtained from experim...
The Krein-von Neumann and the Friedrichs extensions of a nonnegative linear operator or relation (i....
The family of all extensions of a nonclosable hermitian positive linear functional defined on a dens...
. A characterization for a commutative family of operators to have a unitary power dilation is given...
The aim of this paper is to unify the points of view of three recent and independent papers (Ventura...
The Friedrichs extension and the Krein extension of a positive operator in a Krein space are charact...
Positive definite functions arise in various areas in pure and applied mathematics, such as orthogon...
In this book the authors develop a theory of free noncommutative functions, in both algebraic and an...
In [K1] M.G.Krein studied positive definite extensions to the whole real axis of a continuous positi...
We consider approximation methods defined by translates of a positive definite function on a compact...
In this paper we give an analogue of Krein’s formula on the description of generalized resolvents of...
AbstractIt is proved that if a group of unitary operators and a local semigroup of isometries satisf...
This article studies the properties of positive definite, radial functions on free groups following ...
AbstractAn analogue of Krein's extension theorem is proved for operator-valued positive definite fun...
AbstractLet Ω be a locally compact abelian ordered group. We say that Ω has the extension property i...
This monograph deals with the mathematics of extending given partial data-sets obtained from experim...
The Krein-von Neumann and the Friedrichs extensions of a nonnegative linear operator or relation (i....
The family of all extensions of a nonclosable hermitian positive linear functional defined on a dens...
. A characterization for a commutative family of operators to have a unitary power dilation is given...
The aim of this paper is to unify the points of view of three recent and independent papers (Ventura...
The Friedrichs extension and the Krein extension of a positive operator in a Krein space are charact...
Positive definite functions arise in various areas in pure and applied mathematics, such as orthogon...
In this book the authors develop a theory of free noncommutative functions, in both algebraic and an...
In [K1] M.G.Krein studied positive definite extensions to the whole real axis of a continuous positi...
We consider approximation methods defined by translates of a positive definite function on a compact...
In this paper we give an analogue of Krein’s formula on the description of generalized resolvents of...
AbstractIt is proved that if a group of unitary operators and a local semigroup of isometries satisf...
This article studies the properties of positive definite, radial functions on free groups following ...
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