Last year, a quantum computer from Google managed to solve a problem that would have taken a traditional computer 10,000 years in just 200 seconds. One problem was that it was a specially designed problem that had no practical use. But now researchers from Chalmers have built a quantum computer that can solve a practical problem - at least a small part of the problem.
The quantum computer has found the optimal route for aircraft so that the aircraft can be used as efficiently as possible. This is a problem that quickly becomes very complex as the number of planes and destinations grows. Traditional computers quickly find it difficult to manage the enormous choices available to calculate the possible routes for hundreds of aircraft and destinations.
A quantum computer could calculate all possible routes at once using an algorithm called the Quantum Approximate Optimization Algorithm (QAOA) . The researchers have now shown that QAOA works on their quantum computer and that the quantum computer thus has a practical area of use.
Shows the practical benefit
Now, this computer will not revolutionize the aviation industry directly. It has only two quantum bits and can only calculate the routes for two aircraft. But the idea was primarily to prove that a quantum computer can be used to solve practical problems.
- We have shown that we have the ability to solve real problems on our quantum processor. We still have few quantum pieces, but they work well. Our plan has been to first make everything work very well on a small scale, before we scale up, says the experimentalist Jonas Bylander who is one of the leaders of Chalmers quantum computer construction.
Researchers are now working to expand the quantum computer. They are currently trying to reach five quantum pieces and in 2021 they expect to reach at least 20 quantum pieces. According to the researchers' simulations, 25 quantum bits would be enough to solve optimization problems for up to 278 aircraft and then the quantum computer would begin to be of practical use.