There is no physical law to prevent time travel nothing in physics to say it is impossible. So who is to say it can't be done? In Build Your Own Time Machine, acclaimed science writer Brian Clegg takes inspiration from his childhood heroes, Doctor Who and H. G. Wells, to explain the nature of time. How do we understand it and why measure it the way we do? How did the theories of one man change the way time was perceived by the world? Why wouldn't H. G. Wells's time machine have worked? And what would we need to do to make a real one? Build Your Own Time Machine explores the amazing possibilities of quantum entanglement, superluminal speeds, neutron star cylinders and wormholes in space. Brian Clegg applies the most famous of Einstein's theories, special and general relativity, to explain the real science of time travel and discover how possible it really is.