Re: Would an object dropped through a hole in the earth oscillate forever?

yes it would, provided 

1.there was no energy loss from the object

2. the gravitational field was exactly symmetric and time invariant

 now we know that there would probably be air in that hole, and energy 
would be dissipated due to aerodynamic drag even if had no physical contact 
with the sides.


it would definitely be a kind of perpetual motion, but i don't see the 
significance because the total energy of the object + earth system would 
remain constant, so that you could not extract work out of the system 
without making it stop eventually.