I took a long look at one of Heim's papers. OK, I did graduate physics at Caltech, and while I am not a field-theory expert, I know what the math looks like. Heim's papers are full of dense math, but it is gargage, just long algebraic expressions with lots of variabls and numbers. Looks like A/8352+b*113 + (c*3002 - d/200)**2 + ... I've never seen real math that looked like that, I didn't see any differential equations, path integrals, Lie groups, etc. There was no truly sophisticated mathematics in the whole paper, not even calculus. I think the guys was basically one of the many wacky Nazi scientist, like the folks who said planets were hollow.
This is probably also the Nazi antigravity work that I mentioned a few weeks ago, when I got into an argument with a BBC journalist (who thought there was such a thing).