Tube through the Earth

[Captain_Awesome]

@JWT_Kottekoe

Yes, this is exactly my point. There would be a differential in gravity, which is the tidal effect I’ve been talking about. Under the standard assumption, the gravitational force is exactly proportional to the distance along the tube. Thus, the difference in force between your head and your toes is a constant, a few milligrams, it doesn’t matter whether you are at the center of the Earth, the surface, or somewhere in between. The dissipation due to the tides is caused by the time variation of the tidal force. If you have a constant tide, it just stretches things out. It is the act of stretching that requires an input of energy.

But presuming you don’t rotate at the centre of the Earth, wouldn’t the blood slosh back and forth relatively speaking?