Quantum Chess Takes the Game to a New (Sub-Atomic) Level

At last, poor Schroedinger's cat will have something with which to entertain itself while trapped in that box.

At Queen's University in Kingston, Ontario, a computer science professor and student have teamed up to create "quantum chess." The game echoes the behavior of particles on a quantum level, including superimposition, where an object can be in multiple states at once. Just as that kitty-cat can be both alive and dead, a single piece in quantum chess can be a knight and a pawn and a queen. The player has no way of knowing what state the piece will assume until they use it, forcing it to "collapse" into a single state.

Selim Akl, computer science professor, decided to create the game to take away the advantage computers have over their human opponents. Computers are able to calculate all possible moves and their outcomes in classic chess; this version evens the playing field -- or board, as it were -- by expanding those possible outcomes to near-infinity.

"I thought of a game that provides the same kind of unpredictability to both players," Akl said. "The computer cannot possibly search all the possibilities because we can show there are an uncountable number of them."

Alice Wismath, a fourth-year computer science undergrad, took Akl's ideas and created the computer game version, bringing in her own set of rules to make the game playable. The object of the game is to capture the unchanging king piece (as opposed to a mere checkmate), and pieces only change states when on the black tiles of the board.

Quantum chess was first proposed in Akl's paper in the special September issue of Parallel Processing Letters, and was recently put to the test in a tournament at Queen's University.

Ernesto Posse, a postdoctoral researcher who's been playing "classic" chess for 15 years, was one of the winners: "You only know what a piece really is once you touch the piece. Basically, planning ahead is impossible."

Posse claims it was luck that helped him win. After all: "you try to apply some ideas of normal chess, but they rarely work out," as he says.


From CBC via Neatorama. Photo from Kristyn Wallace/Queen's University.