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# A Fourth Spatial Dimension and its Implications on Perception

### yes we can

If I'm not mistaken, a person reaching the speed of light will go into 4th dimension and will see the entire time line of the universe, also this person will be able to see the entire 3-D world folded flat in the same way we look at a 2D drawing.
Reaching that speed is impossible but what happens when you get really close to it ?

### His may be dissapointin to

His may be dissapointin to hear but: most all living creatures are already 4D beings, the brain understands things just fine 4th dimensionally (remember soace and time are not seperate but are "spacetime" and "time" is a subjective illusion, much in the way your eyes give you an illusionary 3D view (but your can process in a 4D manner), its so,ewhat misleading to imply a 3D being's shaodw is 2D, since light and the shadow cast isn't a good corellation, as when you have multiple light sources your shadow ceases being strictly 2D (and not to mention the "entire space" that is "shaded" is also filled you just are not paying attention to it). So in short you already "cast a 3D shadow" (if you've ever been in a dark room with hour eyes open you know "darkness" fills the space it is in so to speak).

4D things cast "action-consequence" shadows if you would like, such as you are in the shadow of every event that took place to create the event you are experiencing at the moment, and so to does that event cast a shadow on every future event that occurs as a consequence of the actions you and other thigs take during said experience.

Pretty simple stuff really!

You miht be trying to describe 5th dimension stuff though. Thats a pretty sketchy area though.

### 1 dimension

Since a 4 Dimensional being would see a shadow in 3 dimension and 3 dimensional beings see shadows in 2 dimension and 2 dimensional see in 1 dimension what would a 1 dimensional being see?

The entire "world" would have a single shadow, which would be a dot. It is pretty mind blowing, but the entire world of Lineland would have one shadow, and maybe two if there was more than one light source. But they would both be dots.

### Does that mean I also exist

Does that mean I also exist in the 4th dimension at the same time?

### 4th dimension concept

3D objects casts 2D shadows which can be seen, but not touched or smelled. 2D objects casts 1D shadows - infinite line. What about 4D objects, surely they must cast 3D shadows and as we live in a 3D universe we are accustom to 3D only and can therefore see 3D shadows that we call ghosts, that can be seen but not touched or smell. Therefore as ghost resemble people from the past, does it mean that when we die we actually upgrade to 4D and travel to another 'world or 'universe' and will continue to do so into 5D, 6D...and so on? Their shadows are seen due to a glitch in the transformation while they're in limbo between the 2 universe awaiting correction. This could also explain why some people have come back from the other side. Maybe due to incorrect alignment with the 4D universe while in limbo between the 2.

### holding a tesseract in your hand

so if we were to hold a miniature model of a real 4-dimensional object in our hand such as a tesseract, does that mean that we would only feel (and more importantly see) only a solid cube that we are holding in our hands even if it is a real bonafide 4 dimensional object?

### Not on your palm , maybe IN it.

First things first , you can't hold the Tesseract on your palm. He has more dimensions that ur palm does. He may choose to stand on a position that co-ordinates to ur palm , but not on it physically. Thats because , although we only perceive 3d (yes we can only see his 3d form) he exists in a 4d space , his fourth dimension just not visible. Its like an apple thats half way through a plane. While it has its other dimension , 2d objects in the plane perceive it as only 1d with possible cues as to its 2nd dimension , just like we can see in only 2d with cues to the 3rd dimension.

Suppose this apple moved up and down in through the plane , the 2d creatures will perceive a series of 1d projections aks lines (corresponding to where the apple's form intersected with the plane). Something similar would happen if we were to interact with the Tesseract. We might see a series 3d forms - thats only theory of course , bur you get the essence.

### Did 2nd dimensional eyesight

Did 2nd dimensional eyesight evolve into 3rd dimensional eyesight and acquiring knowledge of the 4th dimension is limited to an evolutionary process? How do physics, biology and philosophy and their various theories (string theory, quantum physics, evolution, etc.) play into this 4th dimension discussion?

### quite possible. if everything

quite possible. if everything evolved from single cell ameoba, it would take trillions of years for human to evolve into a fourth dimensional being. But is it possible that fourth dimensional beings are all around us? on earth?

### There's still depth!

We evolved from unicellulars - true that. But even they have a 3d factor , depth - say in the order of 10 power -20 or even -1000. Thats still depth. So we have always been evolving into better 3d beings not progressing up the "d-scale". If however the process of evolution is convoluted by a human effort to reach for the fourth d , then perhaps we can all one day be 4d boogey-man creatures , just like the deer becoming giraffe story.

### yo

What if we arrage our receptors in the retina in a 3-d pattern; can we see 4-d?

### yo

No, because they would still be pointing into the third dimension, not the 4th. Consider the lower-dimensional analogue: Can a square, in a flat universe, arrange it's receptors in 2d, in order to see in 3d? Even if you spread out the receptors into a circle, they would still be pointing into the plane of the square's universe (you really want the circular group of receptors to be seeing "up", not forward). In fact, just like in real life, the receptors at the back of the circle would receive no light at all, since they would be in the shadow of those in front. In order for the square to see into the 3d world, his receptors would have to be 'tilted', (or better, tiltable) out of the plane of his flat universe and into the 3rd dimension. Same with us, if we wanted to see in the 4th dimension, we would need a way for our eyes to rotate in the 4th dimension. As far as I know, this is an ability we humans do not possess...

### But what if we could?

What if a third-dimensional creature adjusted the receptors of a second-dimensional creature? Or if a fourth-dimensional creature adjusted the receptors of a third-dimensional creature? If they have perception of the fourth dimension, and could manipulate the eyes of a human - from his perception of their eyes, from his fourth dimension, then I imagine it would be possible. For instance - if I found a two-dimensional creature, with its eyes always facing forward, viewing with two one-dimensional eyes to perceive the second dimension, he could only look forward, backward, up, and down. But if I, as a third-dimensional creature, stood to his left and operated on his eyes to adjust his receptors to the left and right, he would have a new range of vision.
Maybe I'm wrong about all this. If someone can prove so, I would enjoy that. But if not, I will continue living on my fantasies, and hope to eventually come across a fourth-dimensional creature to begin testing.

### It's not just your eyes

It's not just your eyes seeing something. Your eyes feed a signal to your brain to firm a picture. Your brain would have to be able to interpret a 4d signal if you were somehow able to convert eyes to be able to perceive this. Just like your eyes can't see infrared waves. If it could, the brain would have to adapt to interpret what this wavelength means.