Perspective in 4d

  • Thread starter pierce15
  • Start date
  • #1
315
2
Hello,

This might be a bit of a stupid question, but if there were a universe of 4 spatial dimensions and photons behaved in the same way as in ours, would a 4D "hyper-alien" be able to see 4D perspective with only 2 hypershpherical eyes, or would it require more?

In case my question isn't clear, people who are born blind in one eye are not able to see 3D perspective- everything they see looks like a 2D picture. Having 2 eyes enables a human to judge depth. The name for this is stereopsis.
 

Answers and Replies

  • #3
315
2
Why do you think it would be 4?
 
  • #4
12,241
5,953
Why do you think it would be 4?
we use one pair to see depth in the z dimension and one pair to see depth in the 4th dimension.

Its my guess but Im sure a mathematician could provide a better answer with reasoning to support it.
 
  • #5
Danger
Gold Member
9,607
246
I can't help wondering how many pairs of glasses one would need to wear to watch one of their movies.
 
  • #6
12,241
5,953
I can't help wondering how many pairs of glasses one would need to wear to watch one of their movies.
I don't think it would matter extropolating from our latest batch 3D movies I'd say no one would want to see it.
 
  • #7
Drakkith
Staff Emeritus
Science Advisor
21,031
4,852
To my understanding a 4d being would have a 4d eye that is capable of seeing the world as a 3d image similar to how we see the world as a 2d image projected onto our retina. In such a case I would expect those beings to need only 2 eyes to get a perception of depth. However, I base this on nothing but personal intuition which is about as reliable as...uh, something that's not reliable.
 
  • #8
12,241
5,953
To my understanding a 4d being would have a 4d eye that is capable of seeing the world as a 3d image similar to how we see the world as a 2d image projected onto our retina. In such a case I would expect those beings to need only 2 eyes to get a perception of depth. However, I base this on nothing but personal intuition which is about as reliable as...uh, something that's not reliable.
I thought of that answer too but couldn't come up with the mechanics of how a 3D eye might work. I figured people would see via photons and thus you'd need receptors to convert the photons to signals for the brain.

To accomplish a 3D eye, the receptors would have to be arrayed in a 3D structure but then they would interfere with one another making image resolution difficult.

But then again maybe they wouldn't interfere. I recall the example of a knot. Knots can only exist in three dimensions and not four.

Anyway, I can't quite think of the right analogy to analyze this problem.
 
  • #9
11
0
When you look at a cube drawn in a 2D surface, you can see a projection of the third dimension, but no the whole third dimension. When you look at a moving hypercube in the third dimension, you are seeing a projection of the fourth dimension.
 

Related Threads on Perspective in 4d

  • Last Post
Replies
6
Views
2K
  • Last Post
Replies
11
Views
2K
  • Last Post
Replies
6
Views
22K
  • Last Post
Replies
17
Views
3K
  • Last Post
Replies
0
Views
2K
  • Last Post
Replies
12
Views
4K
  • Last Post
Replies
16
Views
3K
Replies
20
Views
1K
  • Last Post
Replies
1
Views
2K
  • Last Post
2
Replies
27
Views
9K
Top