- Funny, but slightly off. Credit - XKCD
The three body gravitational problem is just a stand-in for the more important ones, really - and even that one has issues, since if you really want to know what a simplified gravitational system (the usual example is sun, jupiter and earth) looks like in a few hundred years, you have to iterate on a very fine time grid. By the time you've got to a couple hundred years out - the math errors give you a completely wrong answer anyway, double floating point is a joke at this level. And then there's the weater problem. Or tell me if a point inside +/-1, -1/+2 is in the mandelbrot set without iterating. I dare ya.
Now, in fusors, we have a many-body problem. Call it 10^18 bodies to be conservative (it's really likely to be more). They are moving around in there from a foot/microsecond and on up. We have all of electrons, D+, D2, D2+, D-, D (at least) in there.
All different E/M ratios, and some repel as well as attract. It's so bad that when I called the fine people at SIMION and asked if they could handle it - they told me to keep my money, no way.
Hopefully, some of the math guys will be properly shamed about this and get to work on something other than how many primes live in a range or some silly group theory and solve this one. We need it!
Of course, there might not be much hope if this http://www.zerohedge.com/news/2014-08-2 ... g-stupider is true. It is what I seem to observe myself.
