Asked by: Kay Brooks, Durham
Surprisingly, Einstein’s Theory of Relativity has no problem with particles that travel faster than light – known as tachyons. They just happen to have some very weird properties, like so-called imaginary mass and an ability to travel through time.
Indeed, tachyons are so weird that physicists are mortified if they ever pop up in their theories. Fortunately, the only claim to have detected tachyons, made in 1974 by physicists in Australia, has never been replicated and is now thought to be spurious.
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