quantum annealer

A quantum annealer is like a smart oven: it searches for the lowest point in an energy landscape to find the answer. But many constrained problems, like "pick exactly three items"—can't be loaded directly into such an oven. They have to be translated into unconstrained quadratic formulas, usually by adding penalties.

A metallurgical workshop piled high with aluminum scrap looks like an orchestra out of tune before a concert: each instrument is off-key in its own way. Offcuts of airplane wings, crushed cans, shavings from milling machines: each 'instrument' has its own metallicity, nonlinearly influencing the final 'melody' of strength and thermal conductivity.

Quantum annealing works like a smart way to find a path through a maze: instead of checking every dead end, it uses quantum effects to find the exit faster. But this maze has a quirk: the numbers that describe the walls and corridors must be roughly the same size.

A quantum computer holds atoms in light traps, like marbles in dimples. To read out the answer, you need to photograph each atom and determine whether it's glowing or not. Previously, analyzing such an image took so long that the computer sat idle. Now, engineers have created a specialized board that looks at the photo and instantly finds all the atoms.

A quantum bit, or qubit, is like a coin spinning on a table, able to be both heads and tails at once. For the computer to know what came up, you have to stop the coin and look. Previously, this stopping was done with a delay: data was read out, taken to a regular computer for processing, and only then was the result known.