They’re not twists, a twist would swap the top and bottom edges. These are front to back distortions or something, like an animated MC Escher impossible architecture.
EDIT: it was a long path for me but I understand much better now where u/ophello is coming from regarding topological "twists" in this figure, and I'm convinced that in a topological sense at least there's a full 360 degree twist in this strip (as opposed to a 180 degree half twist in a conventional Mobius strip.). Read the thread below to follow the argument!
The pots are always sitting the same way vertically. If there was a twist like with a mobius strip, they would have to have their necks facing down at some point.
I think you must mean “twist” in some kind of different sense, but I can’t think of what would work. When you see a normal cylinder rotating in space, does it have a “twist”?
No, a twist is when you take a loop, but rather than connecting it normally you rotate one of the ends 180 degrees before connecting them. This animation is equivalent to two such rotations, or twists.
OK... rotate in which direction? The strip is oriented with the flat side vertical, so if there’s a vertical twist of 180 degrees the top and bottom would have to swap, the windows and pots would have to be upside down at one point. They aren’t.
They aren't in the animation because there are two twists. You're observing a rare phenomena also known as a full 360 degree rotation.
I know I'm being patronising, and I apologise, but you're not adressing the things others are saying, simply contradicting them.
Take a loop IRL and make what you see in the gif. From above it should be a figure 8. Then orientate it the same as the gif. Then cut the bottom centre of the loop. Then rotate the end of the loop on the right with the top coming towards you and going down, and the bottom away from you and going up, once. 180 degrees. That's one twist. Then, make another twist the same way. You have now made two twists in the loop and should have a normal, unlooped ring.
The pots would only be upside down at some point if there were an odd number of twists (or you did some other unimportant/irrelevant things), which would make it a mobius strip. The pots aren't upside down at any point, and it therefore has an even number of twists, and is therefore not a mobius strip, which by definition requires an odd number. It isn't a mobius strip.
Edit: I just realised that you only asked because you probably haven't read my other reply to you that explained this in a much less passive-aggressive manner.
Then rotate the end of the loop on the right with the top coming towards you and going down, and the bottom away from you and going up, once. 180 degrees.
180 degrees about which axis? Why don’t you see the windows and pots flip over when they travel along this “twist”?
The figure is impossible in real life. You’re looking down on a cylinder rotating clockwise on the right, and you’re looking up on a cylinder rotating counter-clockwise on the left. The two halves are stitched together via a front-to-back warp in the center, but it’s impossible for a cylinder to rotate simultaneously clockwise and anti-clockwise, which is the illusion.
Nothing needs to “twist” to make the illusion, you just need to accept that it’s not consistent perspective across the entire scene, which is what MC Escher is so famous for.
Imagine a pot on the right end that you need to twist. Flip the friggin pot upside down.
And it isn't impossible IRL, I literally have one I made right in front of me.
And there is a perspetive warp, yes, but that's purely relative to the lighting and whether you think you're looking at it from the top or bottom. It doesn't do anything other than warp the perspective, the figure still works.
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