26 citations · 92 across the 35 of their papers we have counts for
43 papers
Dilation and Model Theory for Pairs of Commuting Contractions
Joseph A. Ball, Haripada Sau
This manuscript is an effort to extend the Sz.-Nagy--Foias dilation and model theory for a single contraction to the case of commuting pair of contractions. Fundamental to the Sz.-…
Functional Models for Commuting Hilbert-space Contractions
Joseph A. Ball, Haripada Sau
We develop a Sz.-Nagy--Foias-type functional model for a commutative contractive operator tuple having equal to a completel…
Dilation theory and functional models for tetrablock contractions
Joseph A. Ball, Haripada Sau
A classical result of Sz.-Nagy asserts that a Hilbert space contraction operator can be dilated to a unitary $\cU$. A more general multivariable setting for these ideas is the…
Models for q-commutative tuples of isometries
Joseph A. Ball, Haripada Sau
A pair of Hilbert space linear operators is said to be -commutative, for a unimodular complex number , if . A concrete functional model for -co…
Interpolation in multivariable de Branges-Rovnyak spaces
Joseph A. Ball, Vladimir Bolotnikov, Sanne ter Horst
We study a general metric constrained interpolation problem in a de Branges-Rovnyak space associated with a contractive multiplier between two Fock spaces al…
Free noncommutative hereditary kernels: Jordan decomposition, Arveson extension, kernel domination
Joseph A. Ball, Gregory Marx, Victor Vinnikov
We discuss a (i) quantized version of the Jordan decomposition theorem for a complex Borel measure on a compact Hausdorff space, namely, the more general problem of decomposing a g…