Suppose the blue portal is instead aligned parallel to and facing the ground. Maybe a 18" off the ground, a little higher than a person is wide. Additionally, the person is standing upright on the track.

In the above scenario, with the ground rushing at the person, does it suddenly "stop," with the person gently falling onto the ground? This is the same problem, I suppose, but from a different perspective.

Now, what if that blue portal is instead only 6" off the ground? Is the person embedded in the ground, or does the universe crash?

[–] name_NULL111653@pawb.social 1 points 1 year ago

I think you would collide with the ground like you were falling face-down, and is there isn't room you'll simply remain half-in half-out. At that point, your front half is still relative to the ground, but the back half is moving with the train, that way your velocity is zero in relation to both portals.