[the_cosmos]

Yeah, I did mistake what you were trying to say. We’re just coming at this from two different sides... physics does have the convention that absolute zero potential is defined at infinity. I was looking at it strictly from a practical circuit perspective, where 'zero' is just wherever we stick the ground probe, and we only ever calculate for the relative deltas. And we generally don't have wires that can make it to the interplanetary medium or the edge of the infinite ground plane :)

[wat10000]

Space is only ~60 miles away, that's not that much wire. Getting one end up there is left as an exercise for the electrician....

I think it all ties together. Ground potential as in sticking things in the actual ground is in practice pretty much the same as that theoretical potential at infinity, because space has enough charged particles flying around to equalize the imbalance. But it doesn't really matter from a practical perspective when making circuits.