As a partner to Volume 1: Dimensional Continuous Models, this monograph provides a self-contained introduction to algebro-geometric solutions of completely integrable, nonlinear, partial differential-difference equations, also known as soliton equations. The systems studied in this volume include the Toda lattice hierarchy, the Kac-van Moerbeke hierarchy, and the Ablowitz-Ladik hierarchy. An extensive treatment of the class of algebro-geometric solutions in the stationary as well as time-dependent contexts is provided. The theory presented includes trace formulas, algebro-geometric initial value problems, Baker-Akhiezer functions, and theta function representations of all relevant quantities involved. The book uses basic techniques from the theory of difference equations and spectral analysis, some elements of algebraic geometry and especially, the theory of compact Riemann surfaces. The presentation is constructive and rigorous, with ample background material provided in various appendices. Detailed notes for each chapter, together with an exhaustive bibliography, enhance understanding of the main results.

Quantum mechanics and the theory of operators on Hilbert space have been deeply linked since their beginnings in the early twentieth century. States of a quantum system correspond to certain elements of the configuration space and observables correspond to certain operators on the space. This book is a brief, but self-contained, introduction to the mathematical methods of quantum mechanics, with a view towards applications to Schroedinger operators. Part 1 of the book is a concise introduction to the spectral theory of unbounded operators. Only those topics that will be needed for later applications are covered. The spectral theorem is a central topic in this approach and is introduced at an early stage. Part 2 starts with the free Schroedinger equation and computes the free resolvent and time evolution. Position, momentum, and angular momentum are discussed via algebraic methods. Various mathematical methods are developed, which are then used to compute the spectrum of the hydrogen atom. Further topics include the nondegeneracy of the ground state, spectra of atoms, and scattering theory. This book serves as a self-contained introduction to spectral theory of unbounded operators in Hilbert space with full proofs and minimal prerequisites: Only a solid knowledge of advanced calculus and a one-semester introduction to complex analysis are required. In particular, no functional analysis and no Lebesgue integration theory are assumed. It develops the mathematical tools necessary to prove some key results in nonrelativistic quantum mechanics. Mathematical Methods in Quantum Mechanics is intended for beginning graduate students in both mathematics and physics and provides a solid foundation for reading more advanced books and current research literature. This new edition has additions and improvements throughout the book to make the presentation more student friendly.

In diesem Lehrbuch werden die mathematischen Grundlagen exakt und dennoch anschaulich und gut nachvollziehbar vermittelt. Sie werden durchgehend anhand zahlreicher Musterbeispiele illustriert, durch Anwendungen in der Informatik motiviert und durch historische Hintergrunde oder Ausblicke in angrenzende Themengebiete aufgelockert. Am Ende jedes Kapitels befinden sich Kontrollfragen, die das Verstandnis testen und typische Fehler bzw. Missverstandnisse ausraumen. Zusatzlich helfen zahlreiche Aufwarmubungen (mit vollstandigem Losungsweg) und weiterfuhrende Ubungsaufgaben das Erlernte zu festigen und praxisrelevant umzusetzen. Dieses Lehrbuch ist daher auch sehr gut zum Selbststudium geeignet. Erganzend wird in eigenen Abschnitten das Computeralgebrasystem Mathematica vorgestellt und eingesetzt, wodurch der Lehrstoff visualisiert und somit das Verstandnis erleichtert werden kann.

In diesem Lehrbuch werden die mathematischen Grundlagen exakt und dennoch anschaulich und gut nachvollziehbar vermittelt. Sie werden durchgehend anhand zahlreicher Musterbeispiele illustriert, durch Anwendungen in der Informatik motiviert und durch historische Hintergrunde oder Ausblicke in angrenzende Themengebiete aufgelockert. Am Ende jedes Kapitels befinden sich Kontrollfragen, die das Verstandnis testen und typische Fehler bzw. Missverstandnisse ausraumen. Zusatzlich helfen zahlreiche Aufwarmubungen (mit vollstandigem Loesungsweg) und weiterfuhrende UEbungsaufgaben das Erlernte zu festigen und praxisrelevant umzusetzen. Dieses Lehrbuch ist daher auch sehr gut zum Selbststudium geeignet. Erganzend wird in eigenen Abschnitten das Computeralgebrasystem Mathematica vorgestellt und eingesetzt, wodurch der Lehrstoff visualisiert und somit das Verstandnis erleichtert werden kann.

This volume contains twenty contributions in the area of mathematical physics where Fritz Gesztesy made profound contributions. There are three survey papers in spectral theory, differential equations, and mathematical physics, which highlight, in particular, certain aspects of Gesztesy's work. The remaining seventeen papers contain original research results in diverse areas reflecting his interests. The topics of these papers range from stochastic differential equations; operators on graphs; elliptic partial differential equations; Sturm-Liouville, Jacobi, and CMV operators; semigroups; to inverse problems.