This knocks me out.
Suppose, theoretically, you could dig a tunnel from one point on the earth all the way through the center of the earth and out the opposite side. Suppose further that you jumped into said tunnel. Gravity would pull you at high speed (very high speed) to the center, but then the same gravity would cause you to decelerate until you coasted comfortably to the surface of the other side of the earth.
The whole trip would last exactly 42 minutes!
In addition, it doesn’t matter which two cities on earth you connected with this tunnel, the trip would still take 42 minutes!
It’s all in the physics.
Ties my cruller in knots, that does.