Praise for Lillian Lieber and "The Einstein Theory of Relativity" Oh, what a delightful book! This is the clearest explanation of relativity availableand the most fun. It s great to have it available again. Whether or not you re a scientist, you will relish this book. Walter Isaacson, author of "Einstein: His Life and Universe" A clear and vivid exposition of the essential ideas and methods of the theory of relativitycan be warmly recommended especially to those who cannot spend too much time on the subject. Albert Einstein If you know high-school math, are not afraid of equations, and want to find out what Einstein really said, read Lillian Lieber s book. She will lead you through special and general relativity, helping you at every step to understand the essential equations, including tensors, with amazing clarity and conciseness. This uniquely charming book remains as vivid as ever and even more helpful, thanks to the excellent new foreward and notes by David Derbes and Robert Jantzen. Peter Pesic, author of "Abel s Proof: An Essay on the Sources and Meaning of Mathematical Unsolvability" and "Sky in a Bottle" Does the nature of time fascinate you? Does gravity seem a mysterious subject? Are you interested in learning just what it is that Einstein actually did that made him so famous? Then this wonderful book is just the thing. I read the original 1945 edition when I was a high-school student in the 1950s, and it had a tremendous impact on me. I predict the same experience for you, or perhaps a young friend, with this new, updated edition. Paul J. Nahin, author of "Time Machines," "Oliver Heaviside," and "Dr. Euler s Fabulous Formula"