WOODY ALLEN once said, “It is impossible to travel faster than light, and certainly not desirable, as one’s hat keeps blowing off.” But he forgot about a strange type of particle – the tachyon.
Named after the Greek word tachus, meaning swift, tachyons seem to break all the rules. If they exist – and no one has yet proved that they do – they would not only travel faster than light, but backwards in time too.
How does the tachyon manage to break these sacrosanct rules? After all, isn’t the speed of light – 300 million metres per second in a vacuum –…
