JUST A MILLIMETRE AWAY from you, there could be another universe. You can't see it, smell it or reach out and touch it. You could only get to it by travelling in a direction that is forbidden. Because we are all prisoners, trapped in a nether dimension that physicists call the braneworld. If they are to be believed, there's far more to our Universe than meets the eye, or even the most powerful telescopes. According to their theories, the familiar three dimensions that contain all the stars and galaxies we see could actually be a membrane - a brane for ...