Kappeler, T., University of Zurich, Switzerland; Poschel, J., University of Zurich, Switzerland

KdV & KAM

2003 XIII, 279 p. Hardcover
3-540-02234-1

In this text the authors consider the Korteweg-de Vries (KdV) equation (ut = - uxxx + 6uux) with periodic boundary conditions. Derived to describe long surface waves in a narrow and shallow channel, this equation in fact models waves in homogeneous, weakly nonlinear and weakly dispersive media in general.

Viewing the KdV equation as an infinite dimensional, and in fact integrable Hamiltonian system, we first construct action-angle coordinates which turn out to be globally defined. They make evident that all solutions of the periodic KdV equation are periodic, quasi-periodic or almost-periodic in time. Also, their construction leads to some new results along the way.

Subsequently, these coordinates allow us to apply a general KAM theorem for a class of integrable Hamiltonian pde's, proving that large families of periodic and quasi-periodic solutions persist under sufficiently small Hamiltonian perturbations.

The pertinent nondegeneracy conditions are verified by calculating the first few Birkhoff normal form terms -- an essentially elementary calculation.

Contents:

1. The Beginning. 2. Classical Background. 3. Birkhoff Coordinates. 4. Perturbed KdV Equations. 5. The KAM Proof. 6. Kuksin's Lemma. 7. Background Material. 8. Psi-Functions and Frequencies. 9. Birkhoff Normal Forms. 10. Some Technicalities. References. Index. Notation

Series: Ergebnisse der Mathematik und ihrer Grenzgebiete. 3. Folge / A Series of Modern Surveys in Mathematics. Vol.. 45

Lam, T.Y., University of California, Berkeley, CA, USA

Exercises in Classical Ring Theory, 2nd ed

2003 Approx. 330 p. Hardcover
0-387-00500-5

" This useful book, which grew out of the author's lectures at Berkeley, presents some 400 exercises of varying degrees of difficulty in classical ring theory, together with complete solutions, background information, historical commentary, bibliographic details, and indications of possible improvements or generalizations. The book should be especially helpful to graduate students as a model of the problem-solving process and an illustration of the applications of different theorems in ring theory. The author also discusses "the folklore of the subject: the 'tricks of the trade' in ring theory, which are well known to the experts in the field but may not be familiar to others, and for which there is usually no good reference". The problems are from the following areas: the Wedderburn-Artin theory of semisimple rings, the Jacobson radical, representation theory of groups and algebras, (semi)prime rings, (semi)primitive rings, division rings, ordered rings, (semi)local rings, the theory of idempotents, and (semi)perfect rings. Problems in the areas of module theory, category theory, and rings of quotients are not included, since they will appear in a later book. "
(T. W. Hungerford, Mathematical Reviews)

Contents: * Preface * Notes to the Reader * Wedderburn-Artin Theory * Jacobson Radical Theory * Introduction to Representation Theory * Prime and Primitive Rings * Introduction to Division Rings * Ordered Structures in Rings * Local Rings, Semilocal Rings, and Idempotents, Perfect and Semiperfect Rings * Name Index * Subject Index

Series: Problem Books in Mathematics.

Boroczky, K. J. ; Kollar, J. ; Szamuely, T. (Eds.)

Higher Dimensional Varieties and Rational Points

2003 Approx. 300 p. Hardcover
3-540-00820-9

Exploring the connections between arithmetic and geometric properties of algebraic varieties has been the object of much fruitful study for a long time, especially in the case of curves. The aim of the Summer School and Conference on "Higher Dimensional Varieties and Rational Points" held in Budapest, Hungary during September 2001 was to bring together students and experts from the arithmetic and geometric sides of algebraic geometry in order to get a better understanding of the current problems, interactions and advances in higher dimension. The lecture series and conference lectures assembled in this volume give a comprehensive introduction to students and researchers in algebraic geometry and in related fields to the main ideas of this rapidly developing area.

Contents:

C. Araujo and J. Kollar: Rational Curves on Varieties.
J.-L. Colliot-Thelene: Points rationnels sur les fibrations.
O. Debarre: Fano Varieties.
B. Hassett: Density of Rational Points on K3 Surfaces and their Symmetric Products.
J. Kollar: Rationally Connected Varieties and Fundamental Groups.
S. J. Kovacs: Families of Varieties of General Type: The Shafarevich Conjecture and Related Problems.
Y. Tschinkel: Fujita's Program and Rational Points.

Series: Bolyai Society Mathematical Studies. Vol.. 12

Georgiadou, M., Stuttgart

Constantin Caratheodory
Mathematics and Politics in Turbulent Times

2003 Approx. 630pp. Hardcover
3-540-44258-8

With breathtaking detail, Maria Georgiadou sheds light on the work and life of Constantin Caratheodory, who until now has been ignored by historians. In her thought-provoking book, Georgiadou maps out the mathematician?s oeuvre, life and turbulent historical surroundings. Descending from the Greek elite of Constantinople, Caratheodory graduated from the military school of Brussels, became engineer at the Assiout dam in Egypt and finally dedicated a lifetime to mathematics and education. He significantly contributed to: calculus of variations, the theory of point set measure, the theory of functions of a real variable, pdes, and complex function theory. An exciting and well-written biography, once started, difficult to put down.

Contents: 1. Origin and the formative years.- 2. Academic Career in Germany.- 3. The Asia Minor Project.- 4. A Scholar of World Reputation.- 5. National Socialism and War.- 6. The Last years.

Manski, C. F., Northwestern University, Evanston, IL, USA

Partial Identification of Probability Distributions

2003 XII, 178 p. Hardcover
0-387-00454-8

Sample data alone never suffice to draw conclusions about populations. Inference always requires assumptions about the population and sampling process. Statistical theory has revealed much about how strength of assumptions affects the precision of point estimates, but has had much less to say about how it affects the identification of population parameters. Indeed, it has been commonplace to think of identification as a binary event ? a parameter is either identified or not ? and to view point identification as a precondition for inference. Yet there is enormous scope for fruitful inference using data and assumptions that partially identify population parameters. This book explains why and shows how. The book presents in a rigorous and thorough manner the main elements of Charles Manski's research on partial identification of probability distributions. One focus is prediction with missing outcome or covariate data. Another is decomposition of finite mixtures, with application to the analysis of contaminated sampling and ecological inference. A third major focus is the analysis of treatment response. Whatever the particular subject under study, the presentation follows a common path. The author first specifies the sampling process generating the available data and asks what may be learned about population parameters using the empirical evidence alone. He then ask how the (typically) setvalued identification regions for these parameters shrink if various assumptions are imposed. The approach to inference that runs throughout the book is deliberately conservative and thoroughly nonparametric.

Contents: Missing Outcomes * Instrumental Variables * Conditional Prediction with Missing Data * Contaminated Outcomes * Regressions, Short and Long * Response-Based Sampling * Analysis of Treatment Response * Monotone Treatment Response * Monotone Instrumental Variables * The Mixing Problem

Series: Springer Series in Statistics.