You know time travel movies talk about how altering the timeline can cause chaos, implode the universe, yadda yadda?
Well, we should probably go ahead and codify those into laws soon, because scientists have just used a quantum computer to effectively reverse time.
ALSO READ:?Time Travel Isn't Just A Dream But Possible Thanks To Complicated Math, Believes Researcher
Ok ok, so they haven't swung reality backwards or anything, but they have demonstrated a phenomenon that goes against the laws of physics. Allow me to explain.
Researchers from the Moscow Institute of Physics and Technology. Along with colleagues from Switzerland and the US, built their "time machine" using a fairly rudimentary quantum computer. In regular computers, information is stored in bits, which is represented as a 0 or a 1. In quantum computing, qubits can be 0, 1, or even both simultaneously.
Anyway, so they designed an experiment called an "evolution program" that basically causes these ordered qubits to change into increasingly complex patterns of zeroes and ones. However, they also had another program designed to modify the state of the quantum computer in such a way that the experiment evolved backwards.
ALSO READ:?China Has Built The World's 1st Quantum Computer, And It's 24,000 Times Faster Than Competitors
Basically, the chaos of the qubits rewound to their starting states and became ordered once more. To someone watching, it would have been like time rewinding.
That's in direct violation of the second law of thermodynamics, which governs how order progresses to chaos. It's like how a pile of dead leaves would scatter if the wind blew at it. If you recorded a video of that and played it backward, it would look completely strange.
And yet, that's exactly what this experiment achieved, by calculating the exact kind of gust needed to blow scattered leaves into a neat pile.
"We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time,"said Dr Gordey Lesovik, lead researcher at the Laboratory of the Physics of Quantum Information at the Moscow Institute of Physics & Technology (MIPT).
Their system was able to perform this metaphorical time reversal with a success rate of 85 percent when using two qubits. When working with three however, it had a 50 percent error rate. However, the researchers believe this error rate isn't insurmountable, they just need more sophisticated hardware.
Just how exactly they'd be able to use apply this sort of experiment to practical uses however is anyone's guess.