Thread: Explain to me the 4th dimension.

^ Serve it down brother, serve it down.

I always thought that 4th dimensional creatures are ghosts and spirits. Things that live in the fourth dimension appearing in the third. Thats why we don't see them fully because its like taking an apple dipping it in ink and printing it in the 2nd dimension. It would look nothing like the apple we know.

But thats just me in bonkers land

Originally Posted by mrdeano

I always thought that 4th dimensional creatures are ghosts and spirits. Thing that live in the fourth dimension appearing in the third. That why we don't see them fully because its like taking an apple dipping it in ink and printing it in the 2nd dimension. It would look nothing like the apple we know.

I can't say I agree with that idea, but I like it.

Even if y is an "artifact" of x, they are still different dimensions, and represent values of different nature. That is not so apparent in a line, but it is when dealing with conic curves, for example. Yet, they are dependent - as are mass and density, for example. One directly affects the other because of its very definition.

Originally Posted by mrdeano

I always thought that 4th dimensional creatures are ghosts and spirits. Things that live in the fourth dimension appearing in the third. Thats why we don't see them fully because its like taking an apple dipping it in ink and printing it in the 2nd dimension. It would look nothing like the apple we know.

But thats just me in bonkers land

We are not in the "3rd" dimension. We are in 3 dimensions. A "fourth dimension being" would be actually one-dimensional, which means it'd be a line or a dot. Dimensions are not ordered. Objects are constituted of a number of dimensions, not an order of them.

Our physical world is constituted of 3 dimensions, that's why we call it 3D - not because dimensions are "different worlds" or something. Matter is, all those new-ageish superstitious bitches sell the idea that a dimension is a kind of different reality.

Originally Posted by Kromoh

We are not in the "3rd" dimension. We are in 3 dimensions. A "fourth dimension being" would be actually one-dimensional, which means it'd be a line or a dot. Dimensions are not ordered. Objects are constituted of a number of dimensions, not an order of them.

Our physical world is constituted of 3 dimensions, that's why we call it 3D - not because dimensions are "different worlds" or something. Matter is, all those new-ageish superstitious bitches sell the idea that a dimension is a kind of different reality.

Our physical world constitutes of many dimensions, string theory has it. We ourselves can only percieve a 3 dimensions at a time.

Originally Posted by Kromoh

Even if y is an "artifact" of x, they are still different dimensions, and represent values of different nature.

I said that the need for a second coordinate is an artifact of the means with which we constructed the line.

Originally Posted by Kromoh

That is not so apparent in a line, but it is when dealing with conic curves, for example. Yet, they are dependent - as are mass and density, for example. One directly affects the other because of its very definition.

What I am saying is most apparent on a line but if you want to do it with conic sections, fine. take the ellipse x^2 + 2y^2 = 4. this gives y =+/- sqrt(2 - x^2/2). so now having chosen x, you have two possible values of y. y is again dependant on x and it is a one dimensional space. I might as well embed it in an n-dimensional space and say that there are n-1 'dependant dimensions'. By what you are trying to say, we are surrounded with an unbounded amount of 'dependant dimensions'. The whole point of dimension is that there are no dependancies between them. What you want to say is that the second coordinate is dependent on the first coordinate when we embed a one dimensional space in a two dimensional space. saying that one dimension depends on another or that one dimensions affects another makes no sense. You are confusing dimensions with coordinates. It's an important but (not so) subtle distinction. Mathemeticians failed to make it until the late 1800's when Peano cooked up this example of a curve that covers a 2 dimensional area so that one could label each point in a two dimensional space with one coordinate. After that, they had to redefine dimension without using the number of independent coordinates and basically arrived the explanation of dimension that I gave with ants and bounded areas to do so.

I should also do the mathematicians walk of shame and say that I was wrong when I said that 1/t maps (-inf, inf) onto (-1, 1). It was actually the first thing that I thought when I woke up this morning so I must of dreamed about it. the function is |x|x/(x^2 + 1) . That was an ugly mistake.

Originally Posted by Dreams4free

Our physical world constitutes of many dimensions, string theory has it. We ourselves can only percieve a 3 dimensions at a time.

You got my point. I also think space has (at least) 4 dimensions, not 3, and that'd explain things like in General Relativity when light makes a curve while not making a curve.

---

Philo, to quote my original post:

Dimensions are just dimensions. Dimensions don't have orders or meaning. They are like independent directions, though dimensions can be mutually dependent. There is no "the" 4th dimension, there can be a 4th dimension, and it can be any dimension you want it to... Time, mass, energy, eccentricity, number of breaths in a second, etc. A graph of speed X gas use X time has 3 dimensions. Basically that.

That is exactly it. A graph of speed X time, for example, has two dependent dimensions, because the definition of one involves the other. There can never be a change in the time value which doesn't affect the speed value (that, of course, assuming space hasn't changed too). That's why they are dependent. Deep inside, all dimensions of the universe (space, time, mass, light, whatever else) are an outcome of the fundamental concept of energy.

Originally Posted by PhilosopherStoned

What you want to say is that the second coordinate is dependent on the first coordinate when we embed a one dimensional space in a two dimensional space.

Originally Posted by Kromoh

That is exactly it. A graph of speed X time, for example, has two dependent dimensions, because the definition of one involves the other. There can never be a change in the time value which doesn't affect the speed value (that, of course, assuming space hasn't changed too). That's why they are dependent.

We're saying the same thing. You're just saying it wrong. The graph is one dimensional. I guess your set in being non-mathematical about it so i'll just let you be.

Well, maybe. What I'm really trying to convey is that dimensions derive from values, instead of values deriving from dimensions. Yes, of course we can take any number we want in any set of dimensions, but that is only hypothetical guessing. Dimensions are just a way of representing values of different nature; they are only made to show how the value in one changes in comparison to changes in another. Basically, a system of iterations.