In a breakthrough study, physicists manage to ‘reverse time’ using a quantum computer
An international team of scientists led by researchers at the Moscow Institute of Physics and Technology demonstrated the possibility of time reversal in a development that contradicts the basic laws of physics, Newsweek reported on Wednesday. The researchers were assisted by colleagues in Switzerland and the United States.
Lead researcher Dr Gordey Lesovik, who heads the Laboratory of the Physics of Quantum Information at the Moscow Institute of Physics and Technology, said, “We have artificially created a state that evolves in a direction opposite to that of the thermodynamic arrow of time.”
The thermodynamic arrow of time refers to the Second Law of Thermodynamics, which states that “disorder” only increases with time, and can never decrease. A direction opposite to this, previously unknown, would mean that the object moves back from a state of chaos to order.
In a study published in the journal
Scientific Reports on March 13, the scientists experimentally showcased time reversal by sending a qubit from a more complex state to a simpler one using an algorithm on an IBM quantum computer. A qubit, or quantum bit, is the basic unit of quantum information. It is the quantum version of a computer binary bit, which can be a one or a zero.
The quantum physicists decided to check if time could spontaneously reverse itself, at least for an individual particle, and for a tiny fraction of a second. As a result, they examined a single electron in empty interstellar space.
“Suppose the electron is localised when we begin observing it. This means that we are pretty sure about its position in space,” said the study’s co-author Andrey Lebedev from the Moscow Institute of Physics and Technology. “The laws of quantum mechanics prevent us from knowing it with absolute precision, but we can outline a small region where the electron is localised.”