Comprehensive coverage of the special theory (frames of reference, Lorentz transformation, relativistic mechanics of mass points, more), the general theory (principle of equivalence, Riemann-Christoffel curvature tensor, more) and the unified theory (Weyl's gauge-invariant geometry, Kaluza's five-dimensional theory and projective field theories, more.) Foreword by Albert Einstein.
The Riddle of Gravitation: Revised and Updated Edition by Peter G. Bergmann Nonmathematical introduction to conceptual foundations of both Newton's and Einstein's theories of gravity features updated material on gravity waves, singularities, and other current topics. 88 illustrations. 1968 edition.
