We all have moments when we wish we could travel back in time and rectify past mistakes, but time travel is littered with issues and paradoxes that go deep to the root of our understanding of physics. Not only does time travel trouble the minds of scientists like Stephen Hawking, it also forms the basis of many of our favourite Sci-Fi stories such as Star Trek, Doctor Who and Back to the Future. So is it possible to travel through time? Have we ever built a time machine? Only time will tell...
Time travel, telepathy, free energy… science-fiction pipe dreams, right? Not according to scientists who are stretching the laws of physics to the brink. Paul Parsons says to hell with the horizon.