"This is a well-written book, edited by Abhay Ashtekar to celebrate 100 years of relativity. It is dedicated to describing how our understanding of space-time structure has evolved since Einstein's path-breaking 1905 paper on special relativity, and how it might further evolve in the next century, and contains, in three parts, contributions from leading researchers, worldwide, who have thought deeply about the nature and consequences of the interplay between geometry and physics that has dominated all the fundamental physics since then."Mathematical Reviews"... is a book of lasting value, serving both as an overview for non-specialists and as a work of reference for specialists ... The book is valuable both as an accessible overview of current research and as a work of reference. I strongly recommend the book for libraries whose users have an interest in gravity research at any level."General Relativity and Gravitation