Also if you dig a hole through Earth (Which is impossible.) what the hell would happen if you jumped down that hole? Would you float in the center?
At the core, everywhere is up.
But, theoretically, if you jumped down the hole, supposing you don't die from the molten metal, you would have the perpetual energy make you go up and down until friction stops you and you basically get stuck at the center.
theoretically
EDIT:
the molten metal would probably slow you down A LOT, unless you blocked that off somehow. same with the solid core, you'd have to get past that