Although Einstein’s theories suggest that nothing can travel faster than the speed of light, two scientists have extended his equations to show what would happen if faster-than-light travel were possible. In effect, they propose that the universe is divided into two worlds – one where everything moves slower than the speed of light and the other where everything travels faster than the speed of light. The laws of physics in the two different worlds act quite differently.

Special relativity, proposed by Albert Einstein in 1905, showed how concepts like speed are all relative: A moving observer will measure the speed of an object to be different than a stationary observer will and the faster you go, the more time seems to slow down (time dilation). Yet special relativity breaks down if two people’s relative velocity, the difference between their respective speeds, approaches the speed of light. Neither Einstein’s theory nor the new extended theory can explain what happens when travel reaches the precise speed-of-light velocity. Both theories break down at that point.

The extended theory however, explains what happens when you travel *faster* than the speed of light, where weird things begin to happen like say, mass at infinite velocity becomes zero. Still, the scientists believe faster-than-light travel is quite possible.

“The actual business of going through the speed of light is not defined. The theory we’ve come up with is simply for velocities greater than the speed of light. I think it’s only a matter of time. Human ingenuity being what it is, it’s going to happen, but maybe it will involve a transportation mechanism entirely different from anything presently envisaged.”

James Hill and Barry Cox’s paper was published Oct. 3 in the journal Proceedings of the Royal Society A: Mathematical and Physical Sciences.