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. If one number is huge and another is tiny, the quantum computer's hardware starts making mistakes.
Scientists took three known ways to 'even out' the numbers before running. The first is like cutting overly long connections into several pieces. The second is replacing numbers with integers in a limited range. The third is adding 'penalties' for values that are too large. Each method was tested on a real D-Wave Advantage quantum computer.
The first method—'lengthening connections'—worked best. It reduced the spread of numbers and made the answers more accurate. The other two methods had only a small effect. It also turned out that some numbers can be left alone: the process of preparing the problem for the quantum computer already reduces their spread.
This means that before running a problem on a quantum annealer, it's worth spending a little time 'grooming' the numbers. Then the machine will make fewer mistakes and more often give the right answer. It's like before a long road trip, we don't just fill up the gas tank but also check the tire pressure.
The D-Wave Advantage quantum computer operates at a temperature of about 0.015 kelvin — colder than outer space.
In the TV series 'Devs,' a quantum computer helps solve problems that ordinary machines can't, but even there, the numbers have to be prepared in advance.