So I was in the shower today...

[Radical Raccoon]

First, thank you for that. And...that you brought up the earthquake bit is ridiculous. Just because there could be a light gas in the center of the earth does not mean that earthquakes will travel through to the other side of the world, because earthquake shock waves dissapate quickly enough that they don't pass out of the crust of the EArth.

Are you sure?

Shockwaves from earthquakes do indeed pass all the way through the earth. It's something they should have taught you way back in like 7th or 8th grade.

Here's a little overview: http://en.wikipedia.org/wiki/Seismology
It's kind of short, so if you don't believe it just do a search in google for something like "seismology core."