This book is an account of the theory of Hardy spaces in one dimension, with emphasis on
some of the exciting developments of the past two decades or so. The last seven of the ten …

Page 1 Operators, Functions, and Systems: An Easy Reading Volume 1: Hardy, Hankel, and
Toeplitz Nikolai K. Nikolski Mathematical Surveys and Monographs Volume 92 American …

We consider approximation of L p functions by Hardy functions on subsets of the circle for
1≦p<∞. After some preliminaries on the possibility of such an approximation which are …

We will study two function algebras QC and QA which arise when one looks at function
theory on the unit disc in (3 from the point of view of functional analysis. Denote bounded …

In 1965 Gohberg and Krein showed that this infimum is attained when X is a Hilbert space
(see [16], Chap. II, Section 7, especially the proof of Cor. 7.1). However, they did not state …

Douglas and Rudin proved that any unimodular function on the unit circle T can be uniformly
approximated by quotients of inner functions. We extend this result to the operator-valued …

Under a certain assumption of $ f $ and $ g $ in ${L^\infty} $ which is considered by
Sarason, a strong separation theorem is proved. This is available to study a Douglas …

Toeplitz Operators Page 1 Operator Theory: Advances and Applications, Vol. 207, 125–133 c©
2010 Springer Basel AG Toeplitz Operators Sheldon Axler Abstract. This article discusses Paul …

Decompositions of the Maximal Ideal Space of $L^\infty$ Page 1 TRANSACTIONS OF THE
AMERICAN MATHEMATICAL SOCIETY Volume 282, Number 1, March 1984 …

Given an L 2 function f on the unit circle T, we put Φ f (z):= P (| f| 2)(z)−| P f (z)| 2, z∈ D,
where D is the open unit disk and P is the Poisson integral operator. The Garsia norm‖ f …