Time machines

"Time Machines explores the history of time travel in fiction; the fundamental scientific concepts of time, spacetime, and the fourth dimension; the speculations of Einstein, Richard Feynman, Kurt Godel, and others; scientific hypotheses about the direction of time, reversed time, and multidimensional time; time-travel paradoxes, and much more." "Time Machines is highly readable even for those with no physics background. The text contains no equations or higher calculus: All the mathematics are contained in appendices that require nothing beyond differential and integral calculus. Time…