Gamers outperform computer at quantum task

Humans show they have something to offer in coping with counterintuitive realm of quantum physics

someone playing the Quantum Moves game

QUANTUM GAMERS  Human intuition has spawned new strategies for quantum computation, thanks to a video game.


Editor’s note: On July 22, 2020, Nature retracted the study described in this article at the authors’ request. “We, the authors, are regretfully retracting this article owing to an error in our computer code that means the quantitative results reported are not valid,” the team writes in the retraction. The error was pointed out by a researcher unaffiliated with the original study.

Human intuition might seem useless in the weird world of quantum mechanics. It’s a peculiar realm in which particles can be in multiple places at once and can tunnel through barriers that should be impenetrable. But, scientists report in a paper published online April 13 in Nature, in a quantum-inspired game, humans bested computers.

“To me it is more than surprising — it is really mind-blowing,” says physicist Tommaso Calarco of Ulm University in Germany, who was not involved in the study.

The researchers, led by physicist Jacob Sherson of Aarhus University in Denmark, based their game on a quantum computer made up of atoms trapped in a grid pattern, and enticed gamers into finding the optimal way to shuttle atoms back and forth. In this type of quantum computer, scientists must move the atoms quickly and precisely in order to make calculations. Unbeknownst to the gamers, they were helping researchers edge closer to the “quantum speed limit”set by the laws of physics at the smallest scales, which caps the speed of such calculations.

In the game, known as Quantum Moves, atoms are represented by colored liquid contained in a well. The player controls another well, using it to collect and move the liquid. But this is no normal fluid: make a wrong move and it spreads out into an uncontrollably sloshing quantum mess.

Story continues after animation

CARRY WATER In Quantum Moves, players drag a well to transport a fluid, representing an atom in a quantum computer, to a target location (purple box). If the player makes a wrong move, the fluid spreads uncontrollably across the screen. ScienceAtHome

The players outperformed the scientists’ computer algorithm, coming up with strategies the computer missed. The researchers then fed the human strategies back into their algorithm to improve the results, thereby drawing closer to the quantum speed limit.

Sherson was surprised at the players’ success. “Maybe we have a tendency to make it too academic and too scary, this world of quantumness,” he says. “What our games do is they sort of force you to form a quantum intuition.”

Sherson now hopes to recruit more Quantum Moves players to help him better understand how humans form their strategies. Computer and mobile versions of the game are available online.

Physics writer Emily Conover has a Ph.D. in physics from the University of Chicago. She is a two-time winner of the D.C. Science Writers’ Association Newsbrief award.

More Stories from Science News on Quantum Physics