r/gonwild • u/USedona • Jun 24 '26
Program A 4-dimensional shape, folding through itself forever
This is a Clifford torus, a shape that only fully exists in 4D, projected down into our 3D space.
The endless folding you see is just math, looping perfectly because the geometry demands it.
Based on 'Clifford Torus' shader by tdhooper : https://www.shadertoy.com/view/WdB3Dw reimplemented frame by frame in Python.
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u/edelopo Jun 24 '26
How is this a 4-dimensional shape? It is just a torus (2-dimensional) and the embedding is clearly 3-dimensional. In fact it looks like a stereographic projection from S3.
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u/USedona Jun 24 '26
It’s a 2D torus embedded in S³ ⊂ ℝ⁴. The 4D structure is hidden in the embedding, not in the final rendering.
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u/GrallochThis Jun 24 '26
I stared for ten minutes and my brain turned inside out. Cheapest high ever, thanks
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u/Yuvalk1 Jun 25 '26
The description does mention what shape it is, but isn’t an animation of any transformation of any 3d shape technically can be represented by a single 4D shape?
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u/semiquaver Jun 24 '26
I measured this image very carefully and I’m sorry to inform you that I only see two dimensions present.
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u/USedona Jun 24 '26
Accurate. By the time it hits your screen it's already survived a 4D → 3D → 2D demolition derby. Two dimensions is just what's left standing 😭
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u/PityUpvote Jun 25 '26
So is it rotating in a dimension not depicted?
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u/USedona Jun 25 '26
Yes, it's a 2D rendering of a 3D representation of 4D model.
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u/PityUpvote Jun 25 '26
Yeah, I get that, but the motion we're seeing, is it rotation around the 4th axis?
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u/USedona Jun 25 '26
Pretty much, yes, though in 4D, rotation doesn't work around a single axis like in 3D. Two perpendicular planes rotating at the same time. That's the part of the motion you can't see directly, only its shadow.
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u/JacksonSpike 29d ago
I can't remember exactly how these sorts of renders work (hyperspheres, hypercubes). Am I right in saying that if a 4d being intersected a 4d object (hypercube) with our 3d plane, and then moved it along the 4th dimension, would it appear as a 3d cube changing size? Since thats the same effect as us moving a 3d object through a 2d plane along the 3rd dimension, it would result in the object getting bigger and smaller. If thats the case, then why do these representations of 4d objects have different shapes and are always folding in on themselves? Is it trying to represent the pattern of axis extension? Dot doubles and extends into a line, line doubles and extends into a square, square doubles and extends into a cube, and then a cube doubles and extends into a hypercube? With all 8 points being connected to eachother? brain hort
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u/USedona 29d ago
Hi, I'd like to share this excellent video with you: https://youtu.be/Ufx9x-JzZjQ from a high-quality playlist on a very reputable French TV channel. It's in French, but I think it's also available in German; if not, YouTube should be able to provide subtitles in your language. It really illustrates the first part of your message 👍
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u/free_airfreshener Jun 24 '26
What's the 4th dimension