One of the problems with QM and QFM in general, is summing infinite series approximately (perturbation theory) ... and if one quantizes the gravitational field ... then normal series techniques don't work (if the graviton is a spin 2 particle anyway) but this lecturer seems outstanding ... what do you think? I never really got good infinite series theory from either math classes or from QM classes.

My primary interest isn't quantum gravity ... but modular arithmetic, but I could see a tie-in and am really interested in seeing what this guy can teach me.