Completely continuous operators on a Hilbert space or even on a Banach space have received considerable attention in the last fifty years. Their study was usually confined to special completely continuous operators or to the discovery of properties common to all of them (for instance, that every such operator admits a proper invariant subspace). On the other hand, interest in spaces of completely continuous operators is comparatively new. Some results of this type may be found implicit in the early work of E. SCHMIDT. Other results are "generally known" and cannot be found explicitly in...

This monograph deals with the application of the method of the extremal metric to the theory of univalent functions. Apart from an introductory chapter in which a brief survey of the development of this theory is given there is therefore no attempt to follow up other methods of treatment. Nevertheless such is the power of the present method that it is possible to include the great majority of known results on univalent functions. It should be mentioned also that the discussion of the method of the extremal metric is directed toward its application to univalent functions, there being no space...

Der hier vorliegende Bericht ist der zweite Teil des Ergebnisberichtes uber additive Zahlentheorie und behandelt, wie schon im Vorwort des ersten Teils erwahnt, spezielle Mengen nichtnegativer ganzer Zahlen. Fur die Untersuchung solcher Mengen genugt zumeist schon die Kennt nis gewisser Struktureigenschaften, so dass die gewonnenen Resultate in der Regel gleich fur ganze Klassen von Mengen Gultigkeit haben. Dieser Gesichtspunkt ist namentlich fur die Abschnitte 18, 19 und 20 massgebend. - Entsprechend der Entwicklung allgemeiner Begriffs bildungen und Satze innerhalb der additiven...

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Bereits seit langerer Zeit hat sich die additive Zahlentheorie als gesonderter Zweig innerhalb der Zahlentheorie herausgebildet; aber erst in den letzten Jahrzehnten hat dieses Gebiet neue Antriebe erhalten. In der klassischen additiven Zahlentheorie waren die Untersuchungs objekte im wesentlichen solche Fragestellungen, die an ganz spezielle Zahlenmengen geknupft sind, wie etwa das GOLDBAcHsche oder das WARINGSche Problem. Diese bei den Probleme waren es aber auch, die den Anstoss zu einer neuen Entwicklung in der additiven Zahlentheorie gaben, als 1930 SCHNIRELMANN in seiner fundamentalen...

Die Einflihrung der idealen Rander in der Theorie der Riemannschen FIachen solI der Erweiterung der Satze aus der Funktionentheorie auf den Fall der beliebigen Riemannschen Flachen dienen, und zwar jener Satze, die sich auf die relativen Rander der schlicht en Gebiete beziehen, wie z. B. das Dirichletsche Problem, das Poissonsche Integral, die Satze von FATOU-NEVANLINNA, BEURLING, PLESSNER, RIEsz. AuBer dem bieten sie ein wertvolles Untersuchungsmittel - mit einer starken intuitiven Basis - flir verschiedene Probleme der Riemannschen Flachen und ermoglichen eine einfachere und durchsichtigere...

The main purpose of the present work is to present to the reader a particularly nice category for the study of homotopy, namely the homo topic category (IV). This category is, in fact, - according to Chapter VII and a well-known theorem of J. H. C. WHITEHEAD - equivalent to the category of CW-complexes modulo homotopy, i.e. the category whose objects are spaces of the homotopy type of a CW-complex and whose morphisms are homotopy classes of continuous mappings between such spaces. It is also equivalent (I, 1.3) to a category of fractions of the category of topological spaces modulo homotopy,...

This monograph is areport on the present state of a fairly coherent collection of problems about which a sizeable literature has grown up in recent years. In this literature, some of the problems have, as it happens, been analyzed in great detail, whereas other very similar ones have been treated much more superficially. I have not attempted to improve on the literature by making equally detailed presentations of every topic. I have also not aimed at encyclopedic completeness. I have, however, pointed out some possible generalizations by stating a number of questions; some of these could...

The most immediate one-dimensional variation problem is certainly the problem of determining an arc of curve, bounded by two given and having a smallest possible length. The problem of deter points mining and investigating a surface with given boundary and with a smallest possible area might then be considered as the most immediate two-dimensional variation problem. The classical work, concerned with the latter problem, is summed up in a beautiful and enthusiastic manner in DARBOUX'S Theorie generale des surfaces, vol. I, and in the first volume of the collected papers of H. A. SCHWARZ. The...

nullane de tantis gregibus tibi digna videtur? rara avis in terra nigroque simillima cygno. Juvenal Sat. VI 161, 165. 1966-JNC visits AN at CornelI. An idea emerges. 1968-JNC is at V. c. L. A. for the Logic Year. The Los Angeles ma- script appears. 1970-AN visits JNC at Monash. 1971-The Australian manuscript appears. 1972-JNC visits AN at Cornell. Here is the result. We gratefully acknowledge support from Cornell Vniversity, Vni- versity of California at Los Angeles, Monash Vniversity and National Science Foundation Grants GP 14363, 22719 and 28169. We are deeply indebted to the many people...