Quantum entanglement is a great way of transmitting information over distances almost instantly, but signal loss restricts the effective range to about 100 miles. So you need the equivalent of signal repeaters along the route – and a group of Chinese physicists have developed a method of boosting the signal via a process called ‘entanglement swapping’ which involves entangling photons that are already entangled. The scientists admit that this is a hard concept for them to get their own heads around; scant hope for us laymen, then.