To solve optimization problems, just add lasers: An ODD device known as an optical ising machine could untangle tricky logistics

Last December, a glitch in the crew-scheduling system for American Airlines threatened to disrupt thousands of flights over the holiday season. The error allowed pilots to drop flights without requiring another pilot to cover for them, imperiling as many as 15,000 trips. And while the airline managed to spot the problem and staff the flights, the snafu was a reminder of how much we depend on computers to schedule the vast array of services and functions on which our societies have become completely dependent. All major airlines, for example, use sophisticated scheduling-optimization algorithms to assign crews to planes. And while the American Airlines incident was not caused directly by the failure of one of these algorithms, the end result was much the same. Such a failure would make it likely that hundreds of thousands of people would be stranded or seriously inconvenienced while the airline sought a solution.