This is a visual description of the mathematics of space-time. It sets out to provide a sort of map of the cosmos, as it is now being revealed by the latest theories of quantum physics. But, just as it is not possible to make a true representation of the spherical Earth on a two-dimensional piece of paper, so also the true nature of the curvature of space-time cannot be shown on any kind of map or diagram. Professor Osserman approaches the subject historically, recounting the discoveries of Newton, Gauss and Riemann. He carries the reader through to the most recent developments in physics and astronomy, revealing the continuous interplay between mathematical theory and scientific observation.