If simulation is possible, we could upgrade reality to 4D
If we knew how to create world simulation, and how to make it working 4D, then humans would be able to plug themselves in, and experience 4D space. Alternatively there could simulated 4D beings, whose sentience could be transferred to robot body in our real 3D space.
There's nothing technically stopping us from simulating 4 spatial dimensions now. In fact, there are several games that utilize a 4th dimension in their gameplay. Here's 8 examples. The problem is that our brains evolved in 3 spatial dimensions and, even if we can conceive of, define the nature of, and to some degree even indirectly imagine a 4th spacial dimension, our brains are hardwired to think in 3 dimensions and our understanding of a 4th spatial dimension can only be in 3 dimensional terms. The software of our brains, and the hardware of our eyes are simply incapable of perceiving and processing a 4th spatial dimension as it truly is. It would always be filtered through the lens of 3 spatial dimensions, projected into a 3 dimensional form that we can understand.
For a good example of this limitation, we regularly show 3 dimensions in film, tv, animations, video games, etc. projected on 2 dimensional surfaces. We can interpret those 2 dimensional images into an understanding of the 3 dimensional spaces being projected, but A) we do not actually perceived them as 3d. We still only see height and width. Depth is imagined largely based on perceived scale and parallax oocclusion. and B) we are only able to see the 3 dimensional space in our minds because that is how our minds always perceive space. In order to make those 2 dimensional images seem actually 3 dimensional, we have to project different 2 dimensional images to each eye with precise focal lengths and angles to mimic our actual eyesight in 3 dimensional space. Only with that stereoscopic view do we actually see 3 dimensionality with actual depth. Now, with that understanding, that it takes 2 projections in 2d to trick our minds into seeing 3d, how would you trick our perception into seeing 4d? How to we make either our eyes or our brains see whatever the 4th dimensional direction is called? A 3rd eye? No, plenty of animals have more than 3 eyes or even compound eyes, and still only perceive 3d. We have to perceive a direction perpendicular to height, width, and depth that does not actually exist. How would you achieve that goal?
I don't think that is actually possible. I think, like those games in the link, even in a simulation we are stuck playing with the 4th dimension via its interaction with and projection onto 3 dimensions because our brains cannot truly process what a 4th spatial dimension would even be.
I’ve always been fascinated by 4D, but a question just came to mind. Would we gain anything by being able to perceive that extra dimension living only in a 3D world? Is there anything we are currently not seeing that may exist in our world? Would we just have x-ray vision?
If there were a 4th spatial dimension and you could see in 4 dimensions, yes, you could see the inside of things that are enclosed in 3 dimensions. It wouldn't be like x-ray vision exactly though. Think about a sphere in 3d. It is enclosed. When you take 2d projections of the sphere by slicing cross-sections of the ball, from a 2d observer on that plane, they would also see an enclosed circular object. But from the 3rd dimensional observer looking down at that cross section they can see everything enclosed in the circle. From the 4th dimension, then it stands to reason they would have a similar view of a 3 dimensional objects innards. But rather than seeing through the object like in an x-ray, they just see the whole thing laid out in every detail at once like we see the insides of the 2d circle.
I think it would depend on how the shapes extend into the 4th dimension.
Where the 2D slice is two circles: if in 3D we have a sphere inside a sphere the inside is occluded, but if we have a ball inside a cylinder the inside is visible from two ends.
Likewise where the 3D objects are a ball inside a ball, they may be two 4D spheres or one might be more like a cylinder.
There’s no reason why a brain can’t interact with 4 dimensional space. You just have to feed accurate 4D data into the brain and it will learn.
Interact with, yes. Process and perceive it as it truly is? I don't believe so, no.
That’s what interact with means: navigate, orient, decide, etc.
There’s nothing about our neural architecture that has “3D” built into the information it can process.
I disagree. I think we are very much hardwired to innately understand 3d space in an intuitive level. All else about higher and lower dimensions is learned experientially and/or academically, and it's near impossible not to understand it in terms that relate to 3 dimensions or math. I also think that thinking about 4 dimensions in relation to 3 dimensions makes it impossible to truly understand 4 dimensional space as a whole. We can describe every detail of it mathematically, but still not be able to visualize it in whole. Regardless, given the fact that there is no 4th spatial dimension, I doubt either of us will ever have a definitive answer.
Is that just based off of something more concrete than what feels right to you? If a neural network on a computer can interact with four dimensional data, why wouldn’t we be able to?
It isn’t as automatic in three dimensions as you make it sound. Based off of the amount of learning and experimentation we do as infants, it seems reasonable to theorize that if a human were to be born in a fourth dimensional realm and to be implanted with some sort of sensory organ(s) that function in the fourth dimension, they would be able to gain an intuitive understanding of that world in the same way that they gain intuitive understandings of this one.
We already experience 4D; our fourth dimension is time.
It's correct, but I meant spatial dimensions.
There are some 4d experimental games. One is a space flight Sim that allows players to move in a fourth dimension, entering and exiting physical space in a semi physics-compatible way. It's really fun and it tends to break your brain a little.
What's the game?
Itch io has several, I can't find the name of the one I tried like 10 years ago. It was just a proof of concept, a freespace like fighter.
There's also one that turns Minecraft into 4 dimensions, or it at least cribs the aesthetic of Minecraft. I forget which. It's been a few years.
According to some physics theories, we're living in a world with at least 11 dimensions.
But we can only sense and understand 3.
Fyi, string theory, which is a popular, well known theory that assumes 11 dimensions, doesn't really have that much appeal in the scientific community. It's still fun to talk about tho
*A fourth dimension can be time.
Time is a very convenient choice for a fourth dimension, but "fourth" is purely namesake. There's no reason we couldn't describe our world in our three familiar spatial coordinates with an additional coordinate for
temperature, for example. We just don't easily conceptualize it that way because it feels less contiguous according to how we currently frame our model of reality.Disclaimer: my sources include internet research and far too much time to think. I'm absolutely open to discussion and new ideas in whatever form.
Edit: Temperature is kind of a bad example at face value, but good conceptually. Hopefully I'm communicating my point at least we'll enough to be comprehended.
https://physics.stackexchange.com/questions/788528/why-are-the-mechanics-of-different-axes-independent-of-each-other
I'd recommend checking out 4d Toys - I believe it is compatible with VR so you could sort of do what you're describing.
You are correct that 4d toys (and other games) already simulate 4 spatial dimensions. But those games all display the 4th dimensional space from a 3 dimensional projection. I think what OP is suggesting is creating a game that displays an actual 4 spatial dimensions. I have argued in another comment that I don't think this is possible in a way that our brains could ever percieve or process due to the limitations of a brain evolved in 3 spatial dimensions.
The subject of how humans might perceive four dimensional space is covered in a later book of three body novels (Remembrance of earth's past series). The author describes is as being able to see into sealed three-dimensional objects as if they had an open top. As such you could easily traverse into sealed rooms etc from such a perspective.
I thought it was quite an interesting idea.
I've read it. Recently actually. It is really cool. It kind of supports my point though. It's hard for those to both comprehend and describe that have been in higher dimensional spaces and much of what they do describe is in 3 dimensional terms, (enclosed spaces being visible as if by an open top being a good example of trying to comprehend a thing that would be uncomprehendable in 4d through a 3d mindset). Of course, it's also written by an author that hasn't actually experienced such things and is also trying to imagine what it would be like to experience his interpretation of the phenomenon, so... not exactly conclusive either way.
::: spoiler Also later in the story When they describe how 3 dimensional space is dropped into 2 dimensions, I think it also illustrates how hard it would be to comprehend 4 dimensions from our 3 dimensional mindset because every bit of 3 dimensional spaces that drops into 2d space would unfold and expand infinitely because there's no way to fit 3 dimensional data completely in 2 dimensions. So trying to comprehend 4 dimensions from a 3 dimensional perspective will likewise always leave gaps :::
Can you just imagine how insufferable 4d tech bros would be? Yeah I'll pass
What exactly are you defining the 4th dimension as...?
Another space dimension, which has same relation to our three X Y Z dimensions, as third dimension Z relation to X Y.
For clarity the word is perpendicularity. A 4th spatial dimension would have to be perpendicular to all 3 other spatial dimensions.
Ah I understand you now, I was confused about you not specifying space when referring to 4D, mb.
Yep and there already is a game that does it. It called 4D Golf and you ca n play it also I'm VR. On the YouTube channel codeparade are a lot of interesting dev logs.
We would have to experience 4D to emulate it.