Fourth Dimension

[RajaRajan]

Help me in knowing the next dimensional space to the one we live in( 3d ). It is not as physics describes - time, but an extension to the axes x, y & z.

[socalgal]

^

ANSWERS TO QUESTIONS POSTED BELOW:

Scary, I moved this here from another forum and the ^ is an edit/bump. http://sysopt.earthweb.com/forum/smile.gif

Pim, that's correct! http://sysopt.earthweb.com/forum/smile.gif




[This message has been edited by socalgal (edited 07-17-2000).]

[Ultima]

What?? The 4th dimension ain't time???

An extension of the normal axes???

You mean like a space beyond normal space???

A place you'd have to be able to see or go into with some sort of dimension travelling device???

I don't know, cause I've never been there.
But everybody is talking about 4th dimension and further, but what proof do we have they even excist.

Okay, theoretically the human rase is a simple creature, which happens to be further evolved then the rest of the inhabitants of the planet.

Maybe human kind has yet to evolve into a stage where they will be able to see more then 3 dimensions.

Pim

[ScaryBinary]

Hey,

I've read a few books on this 4th spacial dimension. It's hard to imagine since we're so 3 dimensional, but it's easier if you think back a few dimensions first.

For example, take the second dimension. Draw a square on a piece of paper, then draw a dot in the middle of the square. Now, from the point of view of that dot, all it can see is the inside of the square, along the flat surface of the paper - there is no "up" or "down" (i.e., the z axis) to a two dimensial thing. Only the x and y axis exist, and the dot can't "see" what's outside the square.

But I'm in a higher dimension than that dot. I can see both the dot and the square, and I can see outside the square. This means that being in dimension N allows us to see everything in all spaces with less than N dimensions. For example, a 4th dimensional being could see me inside my house, even though from my standpoint I'm completely surrounded by walls (the 3 dimensional equivalent of the dot in the square!).

Look for books about "hyperspace." They'll usually talk about 4th and higher spacial dimensions. Considering this topic, one of the most famous pieces of work is a book about "Flatland," where 2 dimensional creatures live and ponder about life in the 3rd dimension (though it's also a politcal message).

Hope this gives you a good starting point!

ScaryBinary

[ScaryBinary]

PS: What's up with that edit, 'Gal?

~Edit~
Oooooohhhhh....never made the connection...!

[This message has been edited by ScaryBinary (edited 07-17-2000).]

[Ultima]

The post was probably not answered for a while, causing it to go down the list.
So, that is why Socalgal put an arrow pointing up as a reply, so that people will know what it would mean.

Right, Socalgal???

Pim

[Worm]

The 4th dimension is difficult to tackle. No one has really been there... so we can only speculate. We don't live in the 3rd dimension, we live 3 dimensionally. The 4th dimension would just be an extension on another axis. I would assume this to be layers upon the X,Y and Z axii. i.e. more than one object occupying the same point, at the same point in time. Imagine if you would this dot we speak so highly of, imagine he becomes 3D, he is now a microscopic sphere. When applied to 4D, he becomes a multilateral spheroid. A "family" of sphere's, individualized by say... color? My thoughts that is.
Worm

[ScaryBinary]

What about this:

1 dimension - the x axis.
2 dimensions - add a y axis perpendicular to the x axis.
3 dimensions - add a z axis perpendicular to the y and x axes.

...so for 4 dimensions, you'd add an axis perpendicular the existing 3 axes. You could spend a week trying to imagine that!

ScaryBinary

[Donkey]

Then there is imaginary space itself to worry about (i.e. i^2=-1).

[RajaRajan]

Thanx for the replies, but it would be more helpful to me if somebody could talk more about it here or to me at my email address :
hai_raj@rediffmail.com

What I need is there any advantage in making computer to think in terms of the fourth dimension, i.e in Graphics. Please do reply ...

[Worm]

It would dramatically reduce performance. Think about it in the array aspect... variable(x) one dimension, each variable takes up only a little bit of memory. 2D variable(x,y) stack space is being limited now, if you have 100 columns and 50 rows we're now talking about 50*100=5000 variables, even if it equals 0 you still have to have room to store the "table". 3D found in new games... variable(x,y,z) 100 columns, 50 rows, 10 azimuth... 100*50*10=50000 wow!! could cause a stack space error now if you are below about 40MB RAM.... 4D (not yet used) variable(x,y,z,i) just by adding 10 imaginary row/columns/what ever you now have 100*50*10*10=500000!!! "OUT OF STACK SPACE!!!!!!" even if you had enough memory to store it, you wouldn't have enough to access it. 3D is very strenous on systems... ie new gpu installed on vcards to reduce the load on the cpu. Stick with 2D and reference a third variable for 3D, this will minimize stack space required and still produce stellar 32bit images. Maybe 10 years down the line when a 1GB SDRAM chip is standard.
Worm

[Jeff7]

We addressed that for a few days in physics. About the only way to make a dimension perpendicular to all 3 existing axes is with a sphere. Now, exactly what something 4-dimensional would look like may be beyond our present capabilities - don't know. We also discussed stuff like subspace and wormholes. Our teacher said stuff like wormholes is very possible, just presently, with our knowledge level, it would take all the energy produced by all the stars in the Universe in the past few billion years to do it. But that's presently. There may come a day when someone finds a sort of 'shortcut' to making wormholes, such to the point that you could just plug you're Wormhole'o'matic into the wall and be at the market instantly.

[RajaRajan]

The thing is that because it would take just a bit of memory we haven't restricted our thought to one dimension or having limited stack space haven't let our imagination fly high to third dimension as in the case of virtual reality environment. So then why should we restrict our thoughts to three dimensions saying that it would cause "OUT OF STACK SPACE!!!!!!" if we go for higher dimensions. This is what I'm interested to know it. We had made 3d perspectively/ parallely to be 2d ( Games like Quake3 etc. ). So why not 4d to 3d and in turn to 2d ?

[Jonty]

Further to Scarybinarys first reply to this, I understand that as well as the 4th dimensional being seeing someone in their house, the being could also reach in and pluck ScaryBinary out of the house (into his dimension?) and leave the house walls completely intact. Onlookers in the room would not see the beings hand (or whatever!) come through the wall but ScaryBinary would be there one minute then disappear.

[ScaryBinary]

Actually, if some 4th dimensional creature decided to pluck me out of my house, I'd see a wierd globby looking thing grab me - a 3rd dimensional "cross-section" of a 4th dimensional being.

Like this: A circle or an oval is a 2 dimensional cross section of a 3 dimensional sphere, right? So if a 4th dimensional monster passed through 3 dimensions, we'd see all sorts of wierd 3 dimensional shapes - globs, spheres, etc - that were cross sections of the various hunks of its body.

Creepy, regardless. I think I'll sleep with the lights on tonight....

Scary http://members.iquest.net/~stonerville/sb02.gif Binary

[Jeff7]

But how likely is it of 4-dimensional beings entering this universe? We 3D beings couldn't exist in a 2D universe; 4D beings probably couldn't exist in this universe for the same reasons.

[Digitalcandy]

Describing a 4 dimmensional object is easy. I saw it on TLC one night. draw a square on a piece of paper. then draw one overlapping it. Connect the axisis together to form a cube. Now draw a cube overlapping the first cube. Connect the axisis to form the 4 dimmensional object. That is exactly how they explained it and drew it on The Learning Channel.

[BFlurie]

Jeff7, of course we exist in a 2-D universe. If I take a 2-D "view" of your midsection, it'd appear as a flat cross-section of your midsection. If I take a 1-D "view" (a point) in you, it'd definitely be a point of "you".

[Wiruz]

Well, computers can work with 4d!

I Read it in a danish science magazine.

This is how:

3D objects cast 2d shadows, which our gyus in flatland would be able to see..

4d objects (which can be computed by supercomputers - distributed.net challenge?) cast 3d shadows (looks kinda wierd... don't know where to find a picture, øv!)

but working on it with our own 'puter? not really... what do you want to use it for anyway?

-Wiruz

btw - also read the article on 4d creatures being able to operate on 3d people (imagine how easy it would be for one of us to do surgery in flatland... we can look directly into their bodies from above... - wierd stuff)

Gee thanx... now u ruined my sleep for at least a week.... i've got a headache...

-Wiruz