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Scientists reversed time using quantum computer

Have you ever imagined the infused tea flowing back into the tea bag or a volcano from “erupting” in reverse? We cannot imagine about these things because we have learned about the second law of thermodynamics which states that the total entropy of an isolated system can never decrease over time. A group of researcher scientist from Russia teamed up with the scientist from the U.S. and Switzerland in order to challenge this fundamental law of energy.

The study’s lead author Gordey Lesovik who heads the Laboratory of the Physics of Quantum Information Technology at MIPT states that “This research is one of the series which adds up to violating the second law of thermodynamics which is closely associated with the notion of arrow of time that puts in position the one way direction of time from past to future.”

The physicists tried to understand if time could reverse itself for a tiny fraction of a second for a particle. They tried to do this by two methods – first by experimenting the electron in empty interstellar space.

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Andrey Lebedev co-author from MIPT and ETH Zurich stated that “If we consider an electron in space and we begin to observe it, we can come to know the position of it. If not the position but at least the area can be decided since the laws of quantum mechanics don’t allow us to understand the exact position of the electron.”

The physicist then adds “The evolution of electron can be explained by Schrödinger’s equation. However, it makes no distinction between the past and the future, the region of space containing the electron will spread out very quickly. The uncertainty of the electron’s position is growing.”

Quantum mechanics travelling wavefunctions

Quantum mechanics travelling wavefunctions (Credit: Maschen/ wikimedia)

Valerii Vinokur, a co-author of the paper, from the Argonne National Laboratory, U.S. adds to the discussion that “Mathematically, it means that under a certain condition of transformation called complex conjugation, the equation will describe a smeared electron localizing back into a small region of space over the same time period. However, this is only possible theoretically and not practically.”

The second method of experimentation was done with the help of quantum computing instead of electrons, made out of two or three basic elements called superconducting qubits. They have four stages of the experiment.

The four stages are as follows:

  • Stage 1: Order
    In the first stage, like the electron was imagined to be localized in space, here, the qubit is initialized in a stage called the zero stage.
  • Stage 2: Degradation
    Similar to the electron being smeared out over an increasingly large region of space, the qubits leave the zero stage and become a complex pattern of zeros and ones.
  • Stage 3: Time Reversal
    In this stage similar to the electron being induced to fluctuation by microwave, here, a special program modifies the state of the quantum computer in such a way that it would then evolve “backward”, from chaos toward order.
  • Stage 4: Regeneration
    Again the evolution program starts from stage 2. Provided that the “kick “ has been launched successfully. The program reverses the state of qubits back into the past.
    It was observed that where two qubits were involved, the success rate was around 85 percent, but where 3 qubits or more than 3 qubits were involved more errors happened and it resulted in only 50 percent of the success rate.

Published Researchhttps://www.nature.com/articles/s41598-019-40765-6

About the author: Kshitij Kumar Moderator
Kshitij has always been passionate about Science and Technology. He is a Mechanical Engineering graduate from IIT Jodhpur. Kshitij has worked in many fields of Science and Marketing. Along with managing backend and technicalities of the website, he is also one of our editors and marketing managers. Kshitij was the one who came up with the idea of connecting people interested in Science and built a team which is now ScienceHook.

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