Scientists build quantum superposition machine of possible future

In the movie 2018 Avengers: war in the infiniteIn one scene, Dr. Strange was looking for 14 million possible futures to look for a single scenario in which the heroes would be victorious. Perhaps he would have had more ease with the help of a quantum computer. A team of researchers from Nanyang Technological University in Singapore (NTU Singapore) and Griffith University in Australia has built a prototype quantum device capable of generating all possible futures in a simultaneous quantum superposition.

"When we think of the future, we are faced with a vast array of possibilities," says NTU Singapore Assistant Professor Mile Gu, who led the development of the quantum algorithm on which the prototype is based. "These opportunities are growing exponentially as we move forward – for example, even if we only have two choices per minute, there are 14 million possible futures in less than half an hour. less than a day, their number exceeds the number of atoms in the universe. "However, what he and his research group have understood, is that a quantum computer can examine all possible futures by placing them in a quantum superposition, similar to the famous Schrödinger cat, both alive and dead.

To carry out this project, they joined the experimental group led by Professor Geoff Pryde of Griffith University. Together, the team has developed a specially designed quantum photonics information processor in which the potential future outcomes of a decision process are represented by the locations of photons – quantum particles of light. They then demonstrated that the state of the quantum device was a superposition of multiple future potentials, weighted by their probability of realization.

"The operation of this device is inspired by Nobel laureate Richard Feynman," said Dr. Jayne Thompson, a member of the Singapore team. "When Feynman started studying quantum physics, he realized that when a particle moves from point A to point B, it does not necessarily follow a single path. instead, it crosses all possible paths connecting the points simultaneously, and our work extends this phenomenon and exploits them to model future statistics. "

The machine has already demonstrated an application: to measure how much our preference for a specific choice in the present has an impact on the future. "Our approach is to synthesize a quantum superposition of all possible futures for each bias." Farzad Ghafari, a member of the experimental team, explains: "By interfering these overlays with each other, we can totally avoid looking at each possible future individually." In fact, many artificial intelligence algorithms (AI The current ones learn by seeing how small changes in their behavior can lead to different future outcomes, so our techniques can enable quantum enhanced AIs to learn the effect of their actions much more efficiently. "

The team notes that even if their current prototype simulates at most 16 futures simultaneously, the underlying quantum algorithm can in principle evolve without limit. "That's what makes the pitch so exciting," Pryde said. "That's a lot like the classic computers of the 1960s. Although few can imagine the many uses of conventional computers in the 1960s, we still do not know what quantum computers can do." Each discovery of a new application provides new impetus for their technological development ".