The programme of the Conference at El Escorial included 4 main courses of 3-4 hours. Their content is reflected in the four survey papers in this volume (see above). Also included are the ten 45-minute lectures of a more specialized nature.

It is well known that there are close relations between classes of singularities and representation theory via the McKay correspondence and between representation theory and vector bundles on projective spaces via the Bernstein-Gelfand-Gelfand construction. These relations however cannot be considered to be either completely understood or fully exploited. These proceedings document recent developments in the area. The questions and methods of representation theory have applications to singularities and to vector bundles. Representation theory itself, which had primarily developed its methods for Artinian algebras, starts to investigate algebras of higher dimension partly because of these applications. Future research in representation theory may be spurred by the classification of singularities and the highly developed theory of moduli for vector bundles. The volume contains 3 survey articles on the 3 main topics mentioned, stressing their interrelationships, as well as original research papers.

The past several years have witnessed a striking number of important developments in Complex Analysis. One of the characteristics of these developments has been to bridge the gap existing between the theory of functions of one and of several complex variables. The Special Year in Complex Analysis at the University of Maryland, and these proceedings, were conceived as a forum where these new developments could be presented and where specialists in different areas of complex analysis could exchange ideas. These proceedings contain both surveys of different subjects covered during the year as well as many new results and insights. The manuscripts are accessible not only to specialists but to a broader audience. Among the subjects touched upon are Nevanlinna theory in one and several variables, interpolation problems in Cn, estimations and integral representations of the solutions of the Cauchy-Riemann equations, the complex Monge-AmpA]re equation, geometric problems in complex analysis in Cn, applications of complex analysis to harmonic analysis, partial differential equations.

All the papers in this volume are research papers presenting new results. Most of the results concern semi-simple Lie groups and non-Riemannian symmetric spaces: unitarisation, discrete series characters, multiplicities, orbital integrals. Some, however, also apply to related fields such as Dirac operators and characters in the general case.

This book provides an introduction to the theory of existentially closed groups, for both graduate students and established mathematicians. It is presented from a group theoretical, rather than a model theoretical, point of view. The recursive function theory that is needed is included in the text. Interest in existentially closed groups first developed in the 1950s. This book brings together a large number of results proved since then, as well as introducing new ideas, interpretations and proofs. The authors begin by defining existentially closed groups, and summarizing some of the techniques that are basic to infinite group theory (e.g. the formation of free products with amalgamation and HNN-extensions). From this basis the theory is developed and many of the more recently discovered results are proved and discussed. The aim is to assist group theorists to find their way into a corner of their subject which has its own characteristic flavour, but which is recognizably group theory.

From 1-4 April 1986 a Symposium on Algebraic Groups was held at the University of Utrecht, The Netherlands, in celebration of the 350th birthday of the University and the 60th of T.A. Springer. Recognized leaders in the field of algebraic groups and related areas gave lectures which covered wide and central areas of mathematics. Though the fourteen papers in this volume are mostly original research contributions, some survey articles are included. Centering on the Symposium subject, such diverse topics are covered as Discrete Subgroups of Lie Groups, Invariant Theory, D-modules, Lie Algebras, Special Functions, Group Actions on Varieties.

These notes are a record of a course given in Algiers from lOth to 21st May, 1965. Their contents are as follows. The first two chapters are a summary, without proofs, of the general properties of nilpotent, solvable, and semisimple Lie algebras. These are well-known results, for which the reader can refer to, for example, Chapter I of Bourbaki or my Harvard notes. The theory of complex semisimple algebras occupies Chapters III and IV. The proofs of the main theorems are essentially complete; however, I have also found it useful to mention some complementary results without proof. These are indicated by an asterisk, and the proofs can be found in Bourbaki, Groupes et Algebres de Lie, Paris, Hermann, 1960-1975, Chapters IV-VIII. A final chapter shows, without proof, how to pass from Lie algebras to Lie groups (complex-and also compact). It is just an introduction, aimed at guiding the reader towards the topology of Lie groups and the theory of algebraic groups. I am happy to thank MM. Pierre Gigord and Daniel Lehmann, who wrote up a first draft of these notes, and also Mlle. Franr: oise Pecha who was responsible for the typing of the manuscript.

Differential Equations and Group Methods for Scientists and Engineers presents a basic introduction to the technically complex area of invariant one-parameter Lie group methods and their use in solving differential equations. The book features discussions on ordinary differential equations (first, second, and higher order) in addition to partial differential equations (linear and nonlinear). Each chapter contains worked examples with several problems at the end; answers to these problems and hints on how to solve them are found at the back of the book. Students and professionals in mathematics, science, and engineering will find this book indispensable for developing a fundamental understanding of how to use invariant one-parameter group methods to solve differential equations.

Coming Home Your Way offers college and university students returning from an education-abroad experience a wealth of pertinent information, opportunities for meaningful reflection, and practical guidance on making the most of their time abroad. Grounded in research and addressing an array of aspects of education abroad - including intercultural communication, changing relationships, and career impact - Coming Home Your Way will be an invaluable tool for any student planning, experiencing, or returning from a stay abroad. Drawing from theory and research from multiple disciplines, and real-world experiences of students who have studied abroad, the volume addresses key themes critical to understanding reentry, including individual differences in taking in experience, communication patterns and approaches, the reentry transition, the nature of relationships in reentry, bridging reentry and career, and more. Within each chapter are opportunities for self-reflection that allow readers to integrate the ideas presented into their own experience. Compelling short fictional accounts add flavor and detail that bring theory to life. Coming Home Your Way provides a window into the complex experience of intercultural reentry. Reentry from an education-abroad experience can be a period of intense growth, and can feel disruptive and confusing while it's happening. The authors explain and explore these complexities in a conversational style that will engage students, and with the rigor expected by their instructors. Like no other book currently on the market, Coming Home Your Way will give college and university students insight into the challenges and intercultural opportunities that reentry offers.