In the quantum chess computer game created by undergraduate computer science student Alice Wismath, a piece that should be a knight could simultaneously also be a queen, a pawn or something else. The player doesn't know what the second state might be or which of the two states the piece will choose when it is moved.[...]
Wismath also chose new rules to make the game workable with its quantum twist. For example, her version of quantum chess requires a player to capture the king, which never changes to another piece, instead of merely delivering a checkmate. Also, pieces change states only when they land on black squares.
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