Bøger i Teubner-Texte Zur Mathematik serien

The present Teubner-Text contains the contributions from the International Workshop "Analysis in Domains and on Manifolds with Singularities", Breitenbrunn, Germany, 30. April-5. May 1990. In recent years the analysis on manifolds with singularities became more and more interesting, not only because of the progress in solving corresponding singular problems in partial differential equations but also of the new relations to other parts of mathematics such as geometry, topology and mathematical physics. Other motivations come from concrete models in engineering and applied sciences which lead to partial differential equations in domains with a piece-wise smooth geometry (conical points, edges, comers, ... , higher singularities), piece-wise smooth data or boundary and transmission conditions, degenerate coefficients, and so on. There are natural relations to the numerical analysis where also the asymptotics of solutions close to the singularities playa role. As for the smooth cases it is necessary to develop structure principles and unified theories that cover as much as possible the huge variety of concrete situations, often being treated by individual papers under very specific assumptions.

It was the last book the outstanding mathematician, mechanician and lecturer S. G. Mikhlin took an active part in writing. Having been completed during his lifetime, this book could not be published in Russia due to well­ know difficulties. Since that time new results in integral equations of elasticity theory have appeared. The works of W. Wendland and his school on numerical methods of solving boundary integral equations, the works of I. Chudinovich on inves­ tigation of non-stationary integral equations, the works of S. Kuznetsov con­ nected with the construction of the fundamental solutions for anisotropic me­ dia and others deserve special mentioning. The authors recognize that though the book is devoted to integral equations of elasticity theory, its contents do not cover all possible directions in this field. So the book does not contain the investigations of pseudo-differential equations of three-dimensional prob­ lems of elasticity theory, connected with the works of R. Goldstein, I. Klein, G. Eskin; the questions of solving by integral transformations (I. Ufland, L. Slepian, B. Buda. e:v); the theory of symbols of pseudo-differential operators on non-smooth surfaces developed in the works of B. Plamenevski et al. and the new methods of numerical solution of pseudo-differential equations as developed by a school of V. Mazya. The present book gives the classical methods of potential theory in elas­ ticity and their development and also the solution of a number of problems which here are published in English for the first time.

Dieses Lehrbuch zu dem Gebiet der angewandten reellen Analysis stellt ma­ thematische Methoden vor, die für das heutige Verständnis der Theorie nicht­ linearer hyperbolischer Erhaltungsgleichungen von Bedeutung sind, aber auch in anderen Gebieten Anwendung finden. Es umfaßt sowohl klassische Themen der Analysis als auch insbesondere Methoden aus den letzten zwanzig Jahren, die noch nicht in der Lehrbuchliteratur eingehend behandelt werden. Das Buch ist an Studierende gerichtet, die am Anfang des Hauptstudiums stehen und denen die Grundlagen der Analysis, gewöhnliche Differentialglei­ chungen sowie die Funktionalanalysis bekannt sind. Es ist versucht worden, möglichst viel im Text oder den Anhängen darzustellen und zu entwickeln. Vorlesungen zur Maßtheorie und über Partielle Differentialgleichungen werden nicht vorausgesetzt. In einigen Fällen mußte allerdings für den Beweis von Aussagen auf einschlägige Literatur verwiesen werden, um den Umfang des Buches in vertretbarem Rahmen zu halten. Eine umfassende Abhandlung des Themas ist nicht möglich, da die Theorie 'der nichtlinearen hyperbolischen Erhaltungsgleichungen ein Gebiet der parti­ ellen Differentialgleichungen ist, in dem selbst fundamentale Konzepte noch nicht ausgereift sind. Es gibt nur Teilgebiete, in denen eine abgerundete Dar­ stellung von Resultaten möglich ist.

The present Teubner-Text contains invited surveys and shorter communications con­ nected with the International Conference "Function Spaces, Differential Operators and Non­ linear Analysis", which took place in Friedrichroda (Thuringia, Germany) from September 20-26, 1992. The main subjects are weil reflected by the table of contents. 55 mathematicians attended the conference, many of them from eastern countries. We take the opportunity to thank DFG for financial support, which enabled us to invite mathematicians from the former socialist countries, and especially from the former Soviet Union, and which gave us the pos­ sibility to maintain and to strengthen our contacts to these centers of the theory of function spaces and its application to PDE's, \li'DE's and approximation theory. The organization of the conference as weil as the final preparation of this text was mostly done by our co-workers in Jena. We wish to thank all of them for the generaus support they gave us far beyond their duties (whatever this means in connection with the organization of a conference). The final preparation of this text was mainly done by Dr. M. Malarski. Fur­ thermore Dr. M. Geisler, Ms. D. Haroske and Dr. W. Sicke! converted some manuscript in readable papers on TEX-standard Ievel. We wish to thank them for doing this time-consuming work. Jena, May 13, 1993 H.-J. Schmeisser H. Triebe! Contents Survey Articles 9 I Herbert Amann Nonhomogeneaus Linear and Quasilinear Elliptic and Parabolic Boundary Value Pr- lems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Gerard Bourdaud The Functional Calculus in Sobolev Spaces . . . . . . . . . . . . . . . . . . . 127 . . . . .

The theory of lattices, initiated by Dedekind in the past centu­ ry, and revived in the thirties by Garrett Birkhoff, F. Klein-Barmen, ore, and von Neumann, is only in our time coming into its own. The fledgling theory was handicapped by a contingent historical circumstance. The peculiarities of mathematical personality of the founders made lattice theory less welcome to the mathematical public of the time than it otherwise might have been. Thus Dedekind was wi­ dely thought in his time to be far too abstract for his own good, and some of his peers, notably Kronecker, did not hesitate to state their loud and clear disapproval. Later on, the tempers of Garrett Birkhoff and John von Neumann clashed with those of some of the "mainstream"' mathematicians of their time. Norman Levinson once related to me the following anecdote about von Neumann. Invited to deliver the weekly mathematics colloquium at Harvard sometime in the thirties, he chose the subject of his current interest, namely, continuous geometries. At the end of the lecture, as the public was streaming out, G. H. Hardy, who was at the time visiting Cambridge, was overheard whispering to G. D. Birkhoff (Gar­ rett's father): "He is quite clearly a very brilliant man, but why does he waste his time on this stuff?" I myself, when still an assistant professor, was once stopped in the hall of M. I. T.

This book is devoted to the estimation of dimension-like characteristics (Hausdorff dimension, fractal dimension, Lyapunov dimension, topological entropy) for attractors(mainly global B-attractors) of ordinary differential equations, time-discrete systems and dynamical systems on finite-dimensional manifolds. The contraction under flows ofparameter-dependent outer measures is shown by introducing varying Lyapunov functions or metric tensors in the calculation of singular values. For the attractors of the Henon and Lorenz systems, exact formulae for the Lyapunov dimension are derived.