Sure, but most PIC methods are centered at their element or local domain. (You can likely even do the same with ewald/nbody). I definitely agree with you though

Sure, but most PIC methods are centered at their element or local domain. (You can likely even do the same with ewald/nbody). I definitely agree with you though if you need high accuracy on position when everything is on the same huge grid. A simulation that computes bulk properties by simulating particles directly is very rare. At least for me. Observable like temperature, electric/magnetic field strength, stress, velocity, etc are much more common outputs. These often all vary over many order of magnitude across a domain. Working with continuum mechanics, performing large inverted solves on matrices in fixed precision, or heck, even an FFT sounds terrifying to guard against overflow.