 We'll now discuss the modification of the previous experiment. For safety reasons, Alice has been replaced by a crash test dummy, who is also called Alice. Now both use the insurance money from the last experiment to build a new garage, but his new one is made from adamantium, which is completely unbreakable. He and Alice decide to repeat the same experiment. So as before, Alice gets into her and drives really really quickly to the garage. As before, from Bob's reference frame, she becomes length contracted and easily spits into the garage, at which point Bob slams shut the door. Now however, Alice's car cannot break through the garage, and once it reaches the opposite wall, it will come to a halt. So in Bob's frame, since it's no longer moving, it will expand back to its original length, but since it can't break through the garage, it'll just crumple, leaving behind a cube-shaped limo. But what about from Alice's reference frame? Now as before, Alice sees the garage flying towards her at speed v, and the garage is length contracted, so it's too short for the limo to fit in. Now however, Alice will bump up against the end wall of the garage, and she won't be able to break through. And so it looks like she'll just come to a halt like this, and Bob won't be able to shut the garage door, meaning we won't get a cube-shaped limo at the end. Now this is a physical outcome. Does the limo end up crumpled to a cube inside a garage where the door has been shut, or does it end up in a situation like this?