The search for a quantum gravity theory, a theory expected to combine the principles of general relativity and quantum theory, has led to some of the most deepest and most difficult conceptual and mathematical questions of modern physics. The present book, addressing these issues in the framework of recent versions of canonical quantization, is the first to present coherently the background for their understanding. Starting with an analysis of the structure of constrained systems and the problems of their quantization, it discusses the canonical formulation of classical relativity from different perspectives and leads to recent applications of canonical methods to create a quantum theory of gravity. The book aims to make accessible the most fundamental problems and to stimulate work in this field.

The book presents state-of-the-art results on the analysis of the Einstein equations and the large scale structure of their solutions. It combines in a unique way introductory chapters and surveys of various aspects of the analysis of the Einstein equations in the large. It discusses applications of the Einstein equations in geometrical studies and the physical interpretation of their solutions. Open problems concerning analytical and numerical aspects of the Einstein equations are pointed out.

Background material on techniques in PDE theory, differential geometry, and causal theory is provided.

Causal relations, and with them the underlying null cone or conformal structure, form a basic ingredient in all general analytical studies of asymptotically flat space-time. The present book reviews these aspects from the analytical, geometrical and numerical points of view. Care has been taken to present the material in a way that will also be accessible to postgraduate students and nonspecialist reseachers from related fields.

Causal relations, and with them the underlying null cone or conformal structure, form a basic ingredient in all general analytical studies of asymptotically flat space-time. The present book reviews these aspects from the analytical, geometrical and numerical points of view. Care has been taken to present the material in a way that will also be accessible to postgraduate students and nonspecialist reseachers from related fields.

The Constraint Equations.- The Penrose Inequality.- The Global Existence Problem in General Relativity.- Smoothness at Null Infinity and the Structure of Initial Data.- Status Quo and Open Problems in the Numerical Construction of Spacetimes.- The Einstein-Vlasov System.- Future Complete U(1) Symmetric Einsteinian Spacetimes, the Unpolarized Case.- Future Complete Vacuum Spacetimes.- The Cauchy Problem on Spacetimes That Are Not Globally Hyperbolic.- Cheeger-Gromov Theory and Applications to General Relativity.- Null Geometry and the Einstein Equations.- Group Actions on Lorentz Spaces, Mathematical Aspects: A Survey.- Gauge, Diffeomorphisms, Initial-Value Formulation, Etc.