These notes present very recent results on compact K hler-Einstein manifolds of positive scalar curvature. A central role is played here by a Lie algebra character of the complex Lie algebra consisting of all holomorphic vector fields, which can be intrinsically defined on any compact complex manifold and becomes an obstruction to the existence of a K hler-Einstein metric. Recent results concerning this character are collected here, dealing with its origin, generalizations, sufficiency for the existence of a K hler-Einstein metric and lifting to a group character. Other related topics such as extremal K hler metrics studied by Calabi and others and the existence results of Tian and Yau are also reviewed. As the rudiments of K hlerian geometry and Chern-Simons theory are presented in full detail, these notes are accessible to graduate students as well as to specialists of the subject.

Over the past 2O years classical Hodge theory has undergone several generalizations of great interest in algebraic geometry. The papers in this volume reflect the recent developments in the areas of: mixed Hodge theory on the cohomology of singular and open varieties, on the rational homotopy of algebraic varieties, on the cohomology of a link, and on the vanishing cycles; L -realization of the intersection cohomology for the cases of singular varieties and smooth varieties with degenerating coefficients; applications of cubical hyperresolutions and of iterated integrals; asymptotic behavior of degenerating variations of Hodge structure; the geometric realization of maximal variations; and variations of mixed Hodge structure. N

The last book XIII of Euclid's Elements deals with the regular solids which therefore are sometimes considered as crown of classical geometry. More than two thousand years later around 1850 Schl fli extended the classification of regular solids to four and more dimensions. A few decades later, thanks to the invention of group and invariant theory the old three dimensional regular solid were involved in the development of new mathematical ideas: F. Klein (Lectures on the Icosa hedron and the Resolution of Equations of Degree Five, 1884) emphasized the relation of the regular solids to the finite rotation groups. He introduced complex coordinates and by means of invariant theory associated polynomial equations with these groups. These equations in turn describe isolated singularities of complex surfaces. The structure of the singularities is investigated by methods of commutative algebra, algebraic and complex analytic geometry, differential and algebraic topology. A paper by DuVal from 1934 (see the References), in which resolutions play an important rele, marked an early stage of these investigations. Around 1970 Klein's polynomials were again related to new mathematical ideas: V. I. Arnold established a hierarchy of critical points of functions in several variables according to growing com plexity. In this hierarchy Kleinls polynomials describe the "simple" critical points."

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This book introduces the reader to modern algebraic geometry. It presents Grothendieck's technically demanding language of schemes that is the basis of the most important developments in the last fifty years within this area. A systematic treatment and motivation of the theory is emphasized, using concrete examples to illustrate its usefulness. Several examples from the realm of Hilbert modular surfaces and of determinantal varieties are used methodically to discuss the covered techniques. Thus the reader experiences that the further development of the theory yields an ever better understanding of these fascinating objects. The text is complemented by many exercises that serve to check the comprehension of the text, treat further examples, or give an outlook on further results. The volume at hand is an introduction to schemes. To get startet, it requires only basic knowledge in abstract algebra and topology. Essential facts from commutative algebra are assembled in an appendix. It will be complemented by a second volume on the cohomology of schemes.

Bei der Herausgabe der KLEINschen Vorlesung uber die hyper- geometrische Funktion erschienen nur zwei Wege gangbar: Entweder eine durchgreifende Umarbeitung, auch im grossen, oder eine moglichst weitgehende Erhaltung der ursprunglichen Form. Vor allem auch aus historischen Grunden wurde der letztere Weg beschritten. Daher ist die Anordnung des Stoffes erhalten geblieben; e,s ist nur, von kleinen Anderungen abgesehen, ein Exkurs uber homogene Schreibweise aus der KLEINschen Vorlesung uber lineare Differentialgleichungen ein- gefugt, ferner sind die Schlussbemerkungen zur geometrischen Theorie im Falle komplexer Exponenten als durch die Arbeiten von F. SCHILLING uberholt, weggelassen. Aus dem obengenannten Grunde sind beispiels- weise auch Entwicklungen beibehalten worden, die heute schon dem Anfanger gelaufig sind (etwa die Ausfuhrungen uber stereographische Projektion). In Rucksicht auf moglichste Erhaltung der KLEINschen Darstellung sind ferner Hinweise des Herausgebers auf inzwischen ge- machte Fortschritte der Wissenschaft vom Texte getrennt als Anmerkun- gen am Schluss zusammengestellt. Diese Hinweise erheben aber in keiner Weise den Anspruch auf Vollstandigkeit. Bei der nicht zu um- gehenden Revision des Textes im einzelnen ist, dem oben angegebenen Gesichtspunkt entsprechend, moglichste Wahrung des personlichen KLEINschen Stils angestrebt. ubrigens habe ich darauf Bedacht genommen, auch dem A nlanger die Lekture durch Anmerkungen und durch Nachweise der KLEINschen Zitate zu erleichtern. Denn zweifellos bieten gerade diese Vorlesungen eine treffliche Erganzung und Weiterfuhrung dessen, was der Studierende mittleren Semesters an Geometrie und Funktionentheorie kennen- gelernt hat.