The article doesn't mention, but also one of the million dollar Millennium Prizes is to do with exactly this. Except for a few very special circumstances (high

The article doesn't mention, but also one of the million dollar Millennium Prizes is to do with exactly this. Except for a few very special circumstances (high energy collisions), we can't get any real answers from Quantum Chromodynamics (QCD) about the nucleus that actually agree with reality - we can barely get any answers at all. The problem is that these equations use what mathematicians, somewhat disdainfully, like to call "formal mathematics". That is to say that they are just a bunch of rules for manipulating symbols on paper that don't really make sense. More like numerology than real mathematics. No one knows if the rules make any sense at all. If you follow the rules in a different order, for example, you get different answers, and no one knows what it means. The "formal" equations are more based on physical understanding and not the usual solidly based "real" mathematics. It is kind of like how people started using complex numbers before they understood why they worked. They knew the square root of minus 1 was nonsense, and yet you get the right answer, but no one knew why. Today it is a similar situation with QCD (except you can hardly get any answers at all). So if you solve this problem (either in the positive or negative) you get 1 million dollars.