Undeterred by the second law of thermodynamics, a team of international scientists set out to invert the scattering of an electron to its original state, thus reversing time.
An international team of scientists managed to return a particle briefly to its past state, according to a peer-review article published Wednesday on Nature’s journal Scientific Reports
To achieve the time reversal, the research team from the Moscow Institute of Physics and Technology, ETH Zurich, and the U.S. Department of Energy (DOE) ran a simulation applying an algorithm for IBM's public quantum computer.
As the authors explain in the quantum world, one scattered particle takes on a fractured quality, spreading in multiple directions. To reverse its quantum evolution would be like reversing the rings created when a stone is thrown into a pond. This, in turn, would mean breaking the second law of thermodynamics, which states that the total entropy (disorder) of an isolated system can never decrease over time; or can it?
Undeterred by the universal law and encouraged by this question, the team set out to implement an experiment which simulated an electron scattering by a two-level quantum system and its related evolution in time.
The electron went from a localized, or "seen" state, to a scattered one. Then the algorithm was applied to throw the process in reverse. As the simulation ran, they watched the particle return to its initial state, "in other words, move back in time, if only by a tiny fraction of a second."
Various tests delivered the same result 85 percent of the time, supporting their conclusions even further. "We did what was considered impossible before," senior scientist Valerii Vinokur from the DOE expressed, as they literally reversed entropy in a closed system.
However, don’t pack your bags just yet as their experiment is nowhere near a "time machine."
The MIT Technology Review quickly published Thursday a rebuttal to these findings. Their argument, supported by the expertise of other quantum scientists, is that as it is a simulation, the team only ran it backward thus creating the idea of time reversal, as done when pressing rewind on a video.
In the original publication, experts do not claim that this is time traveling, but explain that the finding may eventually enable better methods of error correction on quantum computers, where accumulated glitches generate heat and beget new ones.
As quantum error correction is a burgeoning field of research a system that could effectively jump back and clean up errors as it works could could bring the next phase for global computing. Yet the authors added that "as of this moment, it's very hard to imagine all the implications this can have" but are "optimistic, that it will be many."