The visual examples at the bottom feel very impressive. I haven't diced fully in, but it feels like there's points where they need to be, that represent the simulation well.

Where-as the previous grids couldn't adapt to the problem.

Neat to see!

I wonder if this could be applied to electromagnetic simulations. Common systems in that field have even more serious problems with gridding.

For anyone interested they released the code about a decade later: https://arepo-code.org/getting-started