activity
20102022
most citedCrouzeix's Conjecture and related problems

16 citations · 33 across the 11 of their papers we have counts for

collaborators

18 papers

math.FA2022

Decomposable Blaschke products of degree

Asuman Güven Aksoy, Francesca Arici, M. Eugenia Celorrio +1

We study the decomposability of a finite Blaschke product of degree into degree- Blaschke products, examining the connections between Blaschke products, the ellipt…

math.FA2021

Blaschke Products, Level Sets, and Crouzeix's Conjecture

Kelly Bickel, Pamela Gorkin

We study several problems motivated by Crouzeix's conjecture, which we consider in the special setting of model spaces and compressions of the shift with finite Blaschke products a…

math.CV2020

Interpolation in Model Spaces

Pamela Gorkin, Brett D. Wick

In this paper we consider interpolation in model spaces, with a Blaschke product. We study unions of interpolating sequences for two sequences that are far…

math.FA2020★ 16 cited

Crouzeix's Conjecture and related problems

Kelly Bickel, Pamela Gorkin, Anne Greenbaum +3

In this paper, we establish several results related to Crouzeix's conjecture. We show that the conjecture holds for contractions with eigenvalues that are sufficiently well-separat…

math.FA2018

Numerical Range and Compressions of the Shift

Kelly Bickel, Pamela Gorkin

The numerical range of a bounded, linear operator on a Hilbert space is a set in that encodes important information about the operator. In this survey paper, we first…

math.FA2018

Applications of Envelopes

Kelly Bickel, Pamela Gorkin, Trung Tran

Intuitively, an envelope of a family of curves is a curve that is tangent to a member of the family at each point. Here we use envelopes of families of circles to study objects fro…

math.FA2017

Norms of truncated Toeplitz operators and numerical radii of restricted shifts

Pamela Gorkin, Jonathan R. Partington

This paper gives a new approach to the calculation of the numerical radius of a restricted shift operator by linking it to the norm of a truncated Toeplitz operator (TTO), which ca…

math.CV2017

Compressions of the Shift on the Bidisk and their Numerical Ranges

Kelly Bickel, Pamela Gorkin

We consider two-variable model spaces associated to rational inner functions on the bidisk, which always possess canonical -invariant subspaces A particul…

math.CV2015

Thin Sequences

Pamela Gorkin, Brett. D. Wick

We look at thin interpolating sequences and the role they play in uniform algebras, Hardy spaces, and model spaces.

math.FA2015★ 8 cited

Inner functions and operator theory

Isabelle Chalendar, Pamela Gorkin, Jonathan R. Partington

This tutorial paper presents a survey of results, both classical and new, linking inner functions and operator theory. Topics discussed include invariant subspaces, universal opera…

math.CV2014★ 2 cited

Thin Sequences and Their Role in Model Spaces and Douglas Algebras

Pamela Gorkin, Brett D. Wick

We study thin interpolating sequences and their relationship to interpolation in the Hardy space and the model spaces , where is an inner…

math.CV2014★ 6 cited

Thin sequences and the Gram matrix

Pamela Gorkin, Sandra Pott, John E. McCarthy +1

We provide a new proof of Volberg's Theorem characterizing thin interpolating sequences as those for which the Gram matrix associated to the normalized reproducing kernels is a com…

math.CV2013

Thin Sequences and Their Role in Theory, Model Spaces, and Uniform Algebras

Pamela Gorkin, Sandra Pott, Brett D. Wick

In this paper we revisit some facts about thin interpolating sequences in the unit disc from three perspectives: uniform algebras, model spaces, and spaces. We extend the not…

math.CV2011

The group of invariants of an inner function with finite spectrum

Isabelle Chalendar, Pamela Gorkin, Jonathan R. Partington

This paper determines the group of continuous invariants corresponding to an inner function with finitely many singularities on the unit circle ; that is, the continuous ma…

math.FA2010

Numerical ranges of contractions

Chafiq Benhida, Pamela Gorkin, Dan Timotin

A conjecture of Halmos proved by Choi and Li states that the closure of the numerical range of a contraction on a Hilbert space is the intersection of the closure of the numerical…

math.FA2010

Pervasive Algebras and Maximal Subalgebras

Pamela Gorkin, Anthony G. O'Farrell

A uniform algebra on its Shilov boundary is {\em maximal} if is not and there is no uniform algebra properly contained between and . It is {\em essenti…

math.FA2010★ 1 cited

Orbits of non-elliptic disc automorphisms

Eva A. Gallardo-Gutiérrez, Pamela Gorkin, Daniel Suárez

Motivated by the Invariant Subspace Problem, we describe explicitly the closed subspace generated by the limit points in the norm of the orbit of a thin Blaschke produc…

math.CV2010

Approximation by polynomials and Blaschke products having all zeros on a circle

David W. Farmer, Pamela Gorkin

We show that a nonvanishing analytic function on a domain in the unit disc can be approximated by (a scalar multiple of) a Blaschke product whose zeros lie on a prescribed circle e…