In a development that also represents a major advance in our understanding of quantum computers, by using electrons and the unusual world of quantum mechanics, researchers were able to turn back time in an experiment that is the equivalent of causing a broken rack of pool balls to go back into place.
Although scientists have yet to replicate the futuristic scenes of The Jetsons or the 1985 sci-fi classic Back to the Future, researchers from Moscow's Institute of Physics and Technology partnered with scientists in the US and Switzerland to "experimentally demonstrate time reversal - sending a qubit from a more complicated state to a simpler one", writes Newsweek. The study comes out March 13 in Scientific Reports.
(Web Desk) - Scientists have reversed the direction of time with a quantum computer, in a breakthrough study that seems to contradict the basic laws of physics.
"We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time", said Lesovik. The scientists' experiment challenged the second law of thermodynamics, which dictates the direction of events from the past to the future and involves the transition of energy within a system from usable to unusable, The Daily Mail reported. What makes the latter look so absurd is our intuitive understanding of the second law of thermodynamics: An isolated system either remains static or evolves toward a state of chaos rather than order.
It was as if the balls scattered randomly around a pool table went into reverse and packed themselves back into their original pyramid formation.
Quantum physicists from MIPT chose to check if time could spontaneously reverse itself at least for an individual particle and for a tiny fraction of a second. In this way, they follow the laws of quantum mechanics, which are less clear-cut than the classical world humans inhabit.
An electron's physical position is defined by uncertainty, meaning that instead of being a concrete "point" it is a fuzzy state of probabilities smeared across a region of space. Although this phenomenon is not observed in nature, it could theoretically happen due to a random fluctuation in the cosmic microwave background permeating the universe.
A qubit is a unit of information described by a "one", a "zero", or a mixed "superposition" of both states.
It may not quite be the Tardis, but scientists have built what could loosely be described as a time machine.
In the experiment an "evolution program" was launched which caused the qubits to become an increasingly complex changing pattern of zeros and ones.
The scientists then ran a different program, which tells the computer to run "backward". An obviously far-fetched analogy for the billiards example would be someone giving the table a perfectly calculated kick. Next, the evolution pattern would be kickstarted from the second state again and rewind the qubits to their original state and the past.
Nearly in 85% of cases, the two-qubit quantum computer returned back into the initial state.
To put this concept to the test, the scientists formulated two separate hypothesis: Time reversal would require supersystem manipulation to occur and "in most cases", would not likely take place in nature.
The error rate is expected to drop as scientists improve the devices used to be more sophisticated, the researchers behind the discovery said.
Interestingly, the time reversal algorithm itself could prove useful for making quantum computers more precise.