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Distance still works! Think about Flatland - they can't hide "behind" anything, but we still couldn't see the people 20 miles away.

I think it would be possible to hide if you where given a map of where fourth dimensional curvature exists around you but you wouldn’t being able to observe anything different.

What if they close their eyes! Checkmate atheist.

Somehow it triggers my "be scared" response.

They can't see you, the same way you can't see a 2D object.

No, being rotated in the 4th dimension and plopped back down into the third dimension would be horrible and it wouldn't surprise me if it killed you. For one, it would absolutely feel like a Lovecraftian nightmare. Your right arm is now your left. Your heart is in a different side of your chest. The "you" you see in the mirror will be the "you" you've seen in photographs. But look into chirality in chemistry. Your body would suddenly have tons of molecules that are a mirror image of what they should be and work with the mirror images of molecules they used to. Everything already in you would get flipped, but you might be on a ticking clock if you aren't able to get the chiral opposites of necessary amino acids.

https://en.wikipedia.org/wiki/Chirality_(chemistry)

This projection of the 4-dimensional being into 3D space appears as the Mandelbrot set. Weirdly, it appears to be the Mandelbrot set no matter what angle you look at it from in 3D space.

There is a four dimensional set of which the Mandelbrot set and Julia sets are both slices.

yeah but it looks fancy

It's precisely rotation through the higher dimension that cannot be undone in the lower one. So.. nice thought, I think?

There's 4d golf too by code parade.

https://store.steampowered.com/app/2147950/4D_Golf/ https://youtube.com/@codeparade

Is that the one that works in VR? Apparently the effect works even better when you have stereo vision.

I was actually thinking of 4D Toys.

A friend of mine is pretty sure Kenneth Copeland is a part of a fourth dimensional angler fish. He's just out here looking vaguely human and teaching the Bible just wrong enough so that instead of Jesus coming back it's going to be some nightmarish horror.

Also, he eats a pet every few days. Not because he needs meat, but because he feeds off the suffering of children.

We don't! When I was younger I had a theory that the brain is a 3D representation of an organ that exists in a higher dimension. Granted, I had (and still have) no relevant expertise to properly speculate on how that could work, but it was fun to think about.

We actually kinda do perceive a fourth dimension: time. Sure, we infer it from our memories and come up with cause and effect relationships to help us understand it. But we do know it's there.

If there are higher dimensions, say the extra seven asserted by String Theory, then we have breadth (thickness?) along each axis that is non zero. The higher-order string theory dimensions (which communicate particle information like gravity) are tightly rolled up.

Brian Greene uses the metaphore of an ant on a wire who can move along the wire freely, but can't go far laterally. They may be so small that our quantum bits can't drift anywhere, so our liver doesn't abandon us drift along a high-level axis.

If there are flat higher level dimensions, then either a force or some kind of membrane would have to exist to keep our blood from leaking.

That said, when we have pure elements, or even pure minerals or chemicals, they retain the same density (mass to volume, sometimes affected by temperature) which suggests nothing is hiding away in other dimensions whenever we take measurements. If there is room along higher axes for unseen activity, it doesnt bug us enough to work out consistent properties.

Because we see no evidence of a 4th spatial dimension. So if there is a fourth dimension, our universe doesn't seem to have access to it.

Great book! It's in the public domain, you can grab yours here!

Well, that's something I haven't heard in a long, long time.

That depends: In a certain way, we are already 4D creatures, with three spatial and one time dimension. However, in these contexts it‘s often useful to only refer to spatial dimensions. The 4D creature then has 4 spatial dimensions, and shares our time dimension.

But maybe its four spatial dimensions are our three spatial dimensions plus our time, and its time is something else completely? Then, by rotating you, it could place your head at a different time than your feet. But that also breaks causality and stuff.

No, Time is 1 dimension for us. It's 1 temporal dimension, not the same as a spacial dimension. When you see someone say 3+1D or 3D+1D, that usually refers to 3 spacial dimensions, 1 temporal dimension.

No, time is not the same kind of dimension as space.

I think the thing here that confuses a lot of people is that we need to use movement over time to help our brains get some sort of grasp on how 4 spatial dimensions could work.

Think of it like how document scanners work: the scanner can only see a thin line, so to read the whole document it has to pass that line over the paper, which takes time.
On the other hand you have our eyes which can see a 2d plane, so we can see the entire paper at once, no time needed.

So the time needed to scan the paper isn't part of the paper's 2-dimensionality, but it's needed to represent it in 1 dimension.

In the same way we couldn't directly perceive things in 4d, but we could rotate a 4d item through our 3d slice until we've seen all angles of it, and then try to build a mental approximation of how it actually looks.

A concrete example: to map a 3d sphere into 2d, you'd move it through the 2d plane which results in it looking like a circle that appears out of nowhere, grows until it reaches the widest part, then shrinks again until it dissapears.
Similarily, a 4d hypersphere passing through our 3d space would look like a sphere that appears out of nowhere, grows and shrinks, and then disappears again.

There are theories that suggest up to 11 spatial dimensions exist like some string theories.