Inspired at an impressionable age by the work of science fiction writers H.G.Wells and Arthur C Clarke, Paul Davies has thought long and hard about ways to travel in time. Here, the best-selling popular science writer finally reveals how it can be done - without breaking the laws of physics and without causing any earth-shattering paradoxes. Since time is money, time travel is a costly business. But with the help of a handy black hole, or better a wormhole, and a bit of luck, Davies' guide illustrates how this new mode of travel could yet be a viable option. 'An entertaining tour around a fascinating topic, conducted by a world-class physicist' - Sunday Telegraph.