THE conundrum posed by Einstein’s Theory of Relativity that allows space-time to loop back on itself, theoretically allowing time-travel to the past, has been resolved, according to two physicists.

Quantum theory, which describes small particles as both waves and matter, yields probabilities on the location of these particles, the particles appearing – in layman’s terms – where the waves interfere with each other constructively.

Daniel Greenberger, of New York, and Karl Svozil, of Vienna, solved the equations for waves going backwards in time and found they always interfered destructively.

This means the particles do not appear and the conundrum does not arise.

“If you go back quantum mechanically, you would only see alternatives consistent with the world you left behind,” Greenberger said.

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