'Returning to the past is possible'

US quantum physicists theorize that humans can completely build a time machine to change the past.

Artwork: dailypictures.net.

For decades scientists have always thought about the ability to instantaneously move the quantum state of single atoms from one place to another. According to the Telegraph, a group of quantum physics experts at the Massachusetts Institute of Technology in the United States confirmed that with the principles of instantaneous quantum movement and an effect called "postselection", they can make atoms move turn back time.

"It's possible to bring particles (and, in theory, people) from the future into the past , " said Professor Seth Lloyd, the research leader.

Postselection is an important part of quantum computer science. In traditional computers, if one wants to find the solution of an equation, the computer has to try each solution one by one until the correct result is found. In quantum computers, due to the strange behavior of particles that are smaller than atoms (subatomic), the process of finding the solution is simplified by simultaneously testing all solutions and choosing the right result.

Lloyd and his team say, by combining instant teleportation and postselection, humans can bring objects back in time.

In addition, for subatomic particles, there is still a problem to be concerned. In the process of moving back in time, particles can self-destruct, making them unable to reach their destination.

Professor Lloyd claims that these problems will not appear in his method due to the nature of quantum states. Even so, Lloyd's theory cannot lead to the birth of a time machine or something like that. The team only hopes their work will help public opinion better understand physics.