Explain to me the 4th dimension.

**Kuhnada29** · 05-14-2009 07:46 AM

I thought this was the best explanation of 4d yet.

http://www.youtube.com/watch?v=uDaKz...eature=related

"A 4d world implies that there are an infinite number of 3d spaces adjacent to our 3d world" ( parallel universes? )

If i had 3 transparent boxes. And there was an entity in one of the boxes, he would only know of the box he's in. Because he can only experience 3 dimensions of movement. He's constricted into that one box. Yet, I'm a 4d creature so i know that there are more boxes. He might actually think i was crazy if i told him there was more boxes than just the one he's in.

Now if i was a 4d creature, my field of vision would be in 3d. Just as we are 3d, but we can only see in 2d.

So if i had a cube, i would see it in 3d....but i probably would be able to see all sides of it at once. That's as far as i got, before i was lost in that video lol.

So basically being taken into a 4dimensional place is being taken out of a 3d reality... which you can see a multitude of of other 3d realities.

So in my 4d vision, i would see all of the 3d spaces...i'm really lost now, and only think i got part of this right. Cause it's really hard to explain this...but i feel like i know how it is.

a 4D creature would be able to see a multiple of 3d objects within a box(reality?), us 3d creatures can see a multitude of 2d objects ( paper, hands, cup, etc. ) within our rectangle( field of view).

I'm sure all this is extremely complicated in mathematics.

**Xei** · 05-14-2009 06:37 PM

It needn't be to be honest. Any point in four dimensions can be written as

x
y
z
w

and a line, for example, can be easily written in vector form as

r = [x, y, z, w] + t[a, b, c, d]

There's nothing particularly special at all about three dimensions in mathematics. It's an open question why the universe should happen to have three dimensions.