I put a particle of GPMP in the middle of a grid of CLNE, with ctypes EXOT, ELEC, HYGN, and a few NEUT, to adjust the rate of dispersion. It had the effect I'd hoped for, creating nova-like explosive surges. It also did something I had no reason to expect. When there is an explosion, the GPMP particle moves. It jumps, dances, wiggles - then settles down for a while in its new place. I used the Find function to observe it. I also painted it, to make sure it was the same particle, not re-created by some mysterious divine TPT power. I did see it multiply once.

So - has this been observed before? Why/how is it doing it? Something to do with Newtonian gravity? Bug? Feature? I'm just nuts? (no, I know that!)

Yup, I just figured that out! I should know better LOL