4 papers
Nevanlinna counting functions and pull-back measures on maximal ideal space of
Yong-Xin Gao, Yuxia Liang, Ze-Hua Zhou
In this paper we give precise characterizations of the relation between the Nevanlinna counting function and pull-back measure of an analytic self-map of the unit disk near the bou…
Nearly invariant subspaces for shift semigroups
Yuxia Liang, Jonathan R. Partington
Let be a -semigroup on an infinite dimensional separable Hilbert space; a suitable definition of near invariance of a subspace is pre…
Nearly invariant subspaces for operators in Hilbert spaces
Yuxia Liang, Jonathan R. Partington
For a shift operator with finite multiplicity acting on a separable infinite dimensional Hilbert space we represent its nearly invariant subspaces in terms of invarian…
Representing kernels of perturbations of Toeplitz operators by backward shift-invariant subspaces
Yuxia Liang, Jonathan R. Partington
It is well known that the kernel of a Toeplitz operator is nearly invariant under the backward shift . This paper shows that kernels of finite-rank perturbations of Toeplitz o…