An easy to understand collection of the ideas of one of the greatest scientists of the twentieth century including the idea he is most known for, the theory of relativity Redesigned inside and out to have a fresh, appealing look, this new edition of a classic Crown Trade Paperback is a collection of Einstein’s own popular writings on his work and describes the meaning of his main theories in a way virtually everyone can understand.

Robert Geroch builds on Einstein’s work with commentary that addresses the ideas at the heart of the theory, bringing a modern understanding of relativity to the text. He elucidates how special relativity is a reconciliation of the contradictions between the nature of light and the principle of relativity; he expands on Einstein’s treatment of the geometry of space-time and the fundamental notion of an “event”; he explains in detail, but without technical language, the equivalence of inertial and gravitational mass, a cornerstone of general relativity.