3 citations · 3 across the 6 of their papers we have counts for
6 papers
On the diversity of twisted commuting operators
Zbigniew Burdak
Operators are called twisted commuting if the deformation from commutativity is determined by a unitary operator, including multiplication by a unimodular constant. The aim of the…
The Taylor spectrum of pairs of isometries
Zbigniew Burdak, Patryk Pagacz
In the paper we fully describe Taylor spectrum of pairs of isometries given by diagrams. In most cases both isometries in such pairs have non-trivial shift part and its Taylor spec…
An operator theory approach to the evanescent part of a two-parametric weak-stationary stochastic process
Zbigniew Burdak, Marek Kosiek, Patryk Pagacz +1
A new approach to the evanescent part of a two-dimensional weak-stationary stochastic process with the past given by a half-plane is proceed. The classical result due to Helson and…
The decomposition theorems in Baer -rings
Zbigniew Burdak, Marek Kosiek, Patryk Pagacz +1
We show a general decomposition theorem in Baer *-rings. As a consequence the vast majority of decompositions known in the algebra of bounded Hilbert space operators are generalize…
Invariant subspaces of and preserving compatibility
Zbigniew Burdak, Marek Kosiek, Patryk Pagacz +1
Operators of multiplication by independent variables on the space of square summable functions over the torus and its Hardy subspace are considered. Invariant subspaces where the o…
On the unitary part of isometries in commuting, completely non doubly commuting pairs
Zbigniew Burdak, Marek Kosiek, Marek Słociński
There are considered isometries on a Hilbert space. By the Wold theorem any isometry can be decomposed into a unitary operator and a unilateral shift. For a pair of isometries, eve…