It's been awhile... You sever seen a slow-mo of a water balloon being hit by something? There's a wave that kinda travels through it.
Apparently, lightning strikes do the same thing to the electrostatic sphere. One of the super interesting things here is that, if you measure the speed of 'wave', from, say, Altanta to Sydney, the apparent speed is FTL.... but if you measure the distance as through the Earth instead of across its surface, it works out.
It's also why (apparently) spark gap radio works in caves and tunnels.
It's been awhile, and my understanding wasn't great the first time, but.... no? Spark gap radio works in caves, but not in space. EM waves == photons, right? That's Marconi radio.
Apparently, lightning strikes do the same thing to the electrostatic sphere. One of the super interesting things here is that, if you measure the speed of 'wave', from, say, Altanta to Sydney, the apparent speed is FTL.... but if you measure the distance as through the Earth instead of across its surface, it works out.
It's also why (apparently) spark gap radio works in caves and tunnels.