Download or read book The Theory of Subnormal Operators written by John B. Conway and published by American Mathematical Soc.. This book was released on 1991 with total page 454 pages. Available in PDF, EPUB and Kindle. Book excerpt: "In a certain sense, subnormal operators were introduced too soon because the theory of function algebras and rational approximation was also in its infancy and could not be properly used to examine the class of operators. The progress in the last several years grew out of applying the results of rational approximation." from the Preface. This book is the successor to the author's 1981 book on the same subject. In addition to reflecting the great strides in the development of subnormal operator theory since the first book, the present work is oriented towards rational functions rather than polynomials. Although the book is a research monograph, it has many of the traits of a textbook including exercises. The book requires background in function theory and functional analysis, but is otherwise fairly self-contained. The first few chapters cover the basics about subnormal operator theory and present a study of analytic functions on the unit disk. Other topics included are: some results on hypernormal operators, an exposition of rational approximation interspersed with applications to operator theory, a study of weak-star rational approximation, a set of results that can be termed structure theorems for subnormal operators, and a proof that analytic bounded point evaluations exist.
Download or read book Analytic Theory Of Subnormal Operators written by Daoxing Xia and published by World Scientific. This book was released on 2014-12-18 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains an important progress on the theory of subnormal operators in the past thirty years, which was developed by the author and his collaborators. It serves as a guide and basis to students and researchers on understanding and exploring further this new direction in operator theory. The volume expounds lucidly on analytic model theory, mosaics, trace formulas of the subnormal operators, and subnormal tuples of operators on the Hilbert spaces.
Download or read book An Introduction to Models and Decompositions in Operator Theory written by Carlos S. Kubrusly and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: By a Hilbert-space operator we mean a bounded linear transformation be tween separable complex Hilbert spaces. Decompositions and models for Hilbert-space operators have been very active research topics in operator theory over the past three decades. The main motivation behind them is the in variant subspace problem: does every Hilbert-space operator have a nontrivial invariant subspace? This is perhaps the most celebrated open question in op erator theory. Its relevance is easy to explain: normal operators have invariant subspaces (witness: the Spectral Theorem), as well as operators on finite dimensional Hilbert spaces (witness: canonical Jordan form). If one agrees that each of these (i. e. the Spectral Theorem and canonical Jordan form) is important enough an achievement to dismiss any further justification, then the search for nontrivial invariant subspaces is a natural one; and a recalcitrant one at that. Subnormal operators have nontrivial invariant subspaces (extending the normal branch), as well as compact operators (extending the finite-dimensional branch), but the question remains unanswered even for equally simple (i. e. simple to define) particular classes of Hilbert-space operators (examples: hyponormal and quasinilpotent operators). Yet the invariant subspace quest has certainly not been a failure at all, even though far from being settled. The search for nontrivial invariant subspaces has undoubtly yielded a lot of nice results in operator theory, among them, those concerning decompositions and models for Hilbert-space operators. This book contains nine chapters.
Download or read book Operators and Function Theory written by S.C. Power and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 392 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the modern study of Hilbert space operators there has been an increasingly subtle involvement with analytic function theory. This is evident in the analysis of subnormal operators, Toeplitz operators and Hankel operators, for example. On the other hand the operator theoretic viewpoint of interpolation by analytic functions is a powerful one. There has been significant activity in recent years, within these enriching interactions, and the time seemed right for an overview ot the main lines of development. The Advanced Study Institute 'Operators and Function Theory' in Lancaster, 1984, was devoted to this, and this book contains ex panded versions (and one contraction) of the main lecture prog ramme. These varied articles, by prominent researchers, include, for example, a survey of recent results on subnormal operators, recent work of Soviet mathematicians on Hankel and Toeplitz operators, expositions of the decomposition theory and inter polation theory for Bergman, Besov and Bloch spaces, with applic ations for special operators, the Krein space approach to inter polation problems, •• and much more. It is hoped that these proceedings will bring all this lively mathematics to a wider audience. Sincere thanks are due to the Scientific Committee of the North Atlantic Treaty Organisation for the generous support that made the institute possible, and to the London Mathematical Society and the British Council for important additional support. Warm thanks also go to Barry Johnson and the L.M.S. for early guidance, and to my colleague Graham Jameson for much organisational support.
Download or read book SUBNORMAL OPERATORS DILATION THEORY AND THE CLASSES A N DUAL ALGEBRAS written by PATRICK JOHN. SULLIVAN and published by . This book was released on 1986 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: belong to .
Download or read book Weighted Shifts on Directed Trees written by Zenon Jan Jablónski and published by American Mathematical Soc.. This book was released on 2012 with total page 122 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new class of (not necessarily bounded) operators related to (mainly infinite) directed trees is introduced and investigated. Operators in question are to be considered as a generalization of classical weighted shifts, on the one hand, and of weighted adjacency operators, on the other; they are called weighted shifts on directed trees. The basic properties of such operators, including closedness, adjoints, polar decomposition and moduli are studied. Circularity and the Fredholmness of weighted shifts on directed trees are discussed. The relationships between domains of a weighted shift on a directed tree and its adjoint are described. Hyponormality, cohyponormality, subnormality and complete hyperexpansivity of such operators are entirely characterized in terms of their weights. Related questions that arose during the study of the topic are solved as well.
Download or read book Surveys of Some Recent Results in Operator Theory written by Bernard B. Morrel and published by Longman Scientific and Technical. This book was released on 1988 with total page 280 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Operators and Function Theory written by S C Power and published by . This book was released on 1985-04-30 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Subnormal Operators written by John B. Conway and published by Pitman Advanced Publishing Program. This book was released on 1981 with total page 506 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Operator Theory and Complex Analysis written by J. K. Aggarwal and published by Springer Science & Business Media. This book was released on 1993-01-22 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents a set of papers based on the proceedings of the NATO Advanced Research Workshop on Multisensor Fusion for Computer Vision, held in Grenoble, France, in June 1989. The workshop focused on the fusion or integration of sensor information to achieve the optimum interpretation of a scene. The papers cover a broad range of topics, including principles and issues in multisensor fusion, information fusion for navigation, multisensor fusion for object recognition, network approaches to multisensor fusion, computer architectures for multisensor fusion, and applications of multisensor fusion. The authors have documented their own research and, in so doing,have presented the state of the art in the field. Each author is a recognized leader in his or her area in the academic, governmental, or industrial research community. Several contributors present novel points of view on the integration of information. The book gives a representative picture of current progress in multisensor fusion for computer vision among the leading research groups in Europe and North America.
Download or read book Topics in Operator Theory written by Carl M. Pearcy and published by American Mathematical Soc.. This book was released on 1974-12-31 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Deals with various aspects of the theory of bounded linear operators on Hilbert space. This book offers information on weighted shift operators with scalar weights.
Download or read book Polynomially Subnormal Operator Tuples written by Edwin Franks and published by . This book was released on 1991 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Seminormal Operators written by K. Clancey and published by Springer. This book was released on 2006-11-15 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Functional Calculus for Subnormal Operators II written by John B. Conway and published by American Mathematical Soc.. This book was released on 1977 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Let S be a subnormal operator on a Hilbert space [script]H with minimal normal extension [italic]N operating on [italic]K, and let [lowercase Greek]Mu be a scalar valued spectral measure for [italic]N. If [italic]P[infinity symbol]([lowercase Greek]Mu) denotes the weak star closure of the polynomials in [italic]L[infinity symbol]([lowercase Greek]Mu) = [italic]L1[infinity symbol]([lowercase Greek]Mu) then for [script]f in [italic]P[infinity symbol]([lowercase Greek]Mu) it follows that [script]f([italic]N) leaves [script]H invariant; if [script]f([italic]S) is defined as the restriction of [script]f([italic]N) to [script]H then a functional calculus for [italic]S is obtained. This functional calculus is investigated in this paper.
Download or read book Introduction to Operator Theory written by Takashi Yoshino and published by CRC Press. This book was released on 1993-12-05 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt: An introductory exposition of the study of operator theory, presenting an interesting and rapid approach to some results which are not normally treated in an introductory source. The volume includes recent results and coverage of the current state of the field.
Download or read book Subnormal Operators and Representations of Algebras of Bounded Analytic Functions and Other Uniform Algebras written by Thomas L. Miller and published by American Mathematical Soc.. This book was released on 1986 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present memoir lies between operator theory and function theory of one complex variable. Motivated by refinements of the analytic functional calculus of a subnormal operator, the authors are rapidly directed towards difficult problems of hard analysis. Quite specifically, the basic objects to be investigated in this paper are the unital (continuous) algebra homomorphisms [lowercase Greek]Pi : [italic]H[exponent infinity symbol]([italic]G) [rightwards arrow] [italic]L([italic]H), with the additional property that [lowercase Greek]Pi([italic]z) is a subnormal operator.
Download or read book Lectures on Hyponormal Operators written by Mihai Putinar and published by Birkhäuser. This book was released on 2012-12-06 with total page 295 pages. Available in PDF, EPUB and Kindle. Book excerpt: The present lectures are based on a course deli vered by the authors at the Uni versi ty of Bucharest, in the winter semester 1985-1986. Without aiming at completeness, the topics selected cover all the major questions concerning hyponormal operators. Our main purpose is to provide the reader with a straightforward access to an active field of research which is strongly related to the spectral and perturbation theories of Hilbert space operators, singular integral equations and scattering theory. We have in view an audience composed especially of experts in operator theory or integral equations, mathematical physicists and graduate students. The book is intended as a reference for the basic results on hyponormal operators, but has the structure of a textbook. Parts of it can also be used as a second year graduate course. As prerequisites the reader is supposed to be acquainted with the basic principles of functional analysis and operator theory as covered for instance by Reed and Simon [1]. A t several stages of preparation of the manuscript we were pleased to benefit from proper comments made by our cOlleagues: Grigore Arsene, Tiberiu Constantinescu, Raul Curto, Jan Janas, Bebe Prunaru, Florin Radulescu, Khrysztof Rudol, Konrad Schmudgen, Florian-Horia Vasilescu. We warmly thank them all. We are indebted to Professor Israel Gohberg, the editor of this series, for his constant encouragement and his valuable mathematical advice. We wish to thank Mr. Benno Zimmermann, the Mathematics Editor at Birkhauser Verlag, for cooperation and assistance during the preparation of the manuscript.
