4 papers
Non-commutative positive kernels and their matrix evaluations
Dmitry S. Kalyuzhny\uı-Verbovetzki\uı, Victor Vinnikov
We show that a formal power series in non-commuting indeterminates is a positive non-commutative kernel if and only if the kernel on -tuples of matrices of any size obtaine…
On the {Bessmertny\uı} Class of Homogeneous Positive Holomorphic Functions on a Product of Matrix Halfplanes
Dmitry S. Kalyuzhny\uı-Verbovetzki\uı
We generalize our earlier results from \cite{K} on the Bessmertny\uı class of operator-valued functions holomorphic in the open right poly-halfplane which admit representation as a…
Multivariable -contractions
Dmitry S. Kalyuzhny\uı-Verbovetzki\uı
We suggest a new version of the notion of -dilation () of an -tuple of bounded linear operators on a common Hilbert space. We say that $\mathb…
Carathéodory interpolation on the non-commutative polydisk
Dmitry S. Kalyuzhny\uı-Verbovetzki\uı
The Carathéodory problem in the -variable non-commutative Herglotz--Agler class and the Carathéodory--Fejér problem in the -variable non-commutative Schur--Agler class are po…