This book gives a unified treatment of a variety of mathematical systems
generating densities, ranging from one-dimensional discrete time
transformations through continuous time systems described by
integro-partial-differential equations. Examples have been drawn from a
variety of the sciences to illustrate the utility of the techniques
presented. This material was organized and written to be accessible to
scientists with knowledge of advanced calculus and differential
equations. In various concepts from measure theory, ergodic theory, the
geometry of manifolds, partial differential equations, probability
theory and Markov processes, and chastic integrals and differential
equations are introduced. The past few years have witnessed an explosive
growth in interest in physical, biological, and economic systems that
could be profitably studied using densities. Due to the general
inaccessibility of the mathematical literature to the non-mathematician,
there has been little diffusion of the concepts and techniques from
ergodic theory into the study of these "chaotic" systems. This book
intends to bridge that gap.