Most laws in physics work both forward and backward. An important exception, however, is the second set of thermodynamics. It states that in a closed system, the disorder continues to increase. Closely related to this is the concept of the time arrow. As a result, time only runs in one direction: from the past to the future. An example of this may have been experienced in your own kitchen before. A cup falling on the floor shatters into its component parts. The reverse is not possible. It is not worth it to leave the broken pieces: they will not reassemble on their own.
The Qbits in the quantum computer have three states
But at least in a quantum computer, Gordey Lesovik of the Moscow Institute of Physics and Technology and his team have succeeded in actually reversing time. The cloud-usable quantum computer was used for commercial purposes by IBM. The units within the computer are called Qbits. Their state can be described as "one", "zero" or a third form of overlay. In the course of the experiment, the Qbits were initially set to zero. Subsequently, the development first followed the conditions of thermodynamics: The Qbits assumed random states of "zero" or "one". So the disorder increased. However, a special program based on Schrödinger's complex conjugation ensured that the development was reversed.
The error rate is still relatively high
The disorder thus decreased again and the Qbits took the initial state. Or to stay in the picture with the cup: the items actually sit back together. For systems with two Qbits, the trick worked in 85 percent of cases. With three Qbits, however, errors occurred more frequently. Again, however, a reversal of the timeline could be achieved in half of the cases. The researchers also assume that the advancement in quantum computers will also reduce the number of errors. Conversely, the discovery that has now been made helps to better understand how quantum computers work – and could in turn contribute to their further development.