Proper vs. coordinate acceleration

[bob012345]

Indeed, that's correct. Jump off the building, and you won't feel much as long as you are in free fall. The trouble only comes, when you hit the ground, but that's not a contradiction to the GR picture of free fall since at the moment you hit the ground you are no longer in free fall but subject to other interactions (mostly electromagnetic) ;-)).

To experience the correctness of the GR picture of free fall rather go to the IRS (rumor has it NASA offers the possibility some time in the future if you are willing to pay the price ;-)) than jumping off your window.

Thanks, I understand the terminology better now thanks to MTW.

 

[A.T.]

Fine. Jump off a building and don't worry about because your just in free fall along a geodesic which by definition has no proper acceleration. Good luck with that.

There are literally pop songs explaining that:

 

[Ibix]

There are literally pop songs explaining that

Unfortunately, only peer-reviewed songs are acceptable sources for PF.