That's what I was thinking in the first place...matter/energy creates the ripple.
That's not really it tho. Its more like the ripples create matter. Well, the ripples
are matter. But the ripples are not there because the existence of matter causes them, the ripples cause the existence of matter.
The matter-created ripples that I think that you're thinking of, like the bowling ball on a bedsheet analogy, are from the affects of mass on spacetime and happen on a totally different length scale than we are
talking typing about with these ripples.
Is time the 4th dimension or are you talking about another spacial dimension?
Yes, the 4th dem is time.
As for your 2d model being 4d. I am assuming you mean that the flat plane is not really flat but has some unknown depth.
Well if its flat it doesn't have depth
One of the problems with analogies is that people like to add in extra stuff or bring their own presumptions to the analogy.
Its easier to understand if yu drop all those presumptions and take the analogy at face value.
I'm not going to re-type the analogies here so read up on some of the threads and pages you now know of and pay attention to the analogies at face value.
After you learn some more, then ask more questions or start a new thread.
As far as 4d being represented by 2d, its easier to imagine if you reduce the number of demensions. But basically it comes down to the maths and how things are calculated and represented.
For example, lets say we have a cube of LxWxH.
We could represent all three of those deminsions as one deminsion: X
Now, we can appply mathematical funtions to X and calculate with it as one deminsion, like say, 2X or X^2 etc. But that one deminsion, X, represents all three deminsions of the cube and that will affect the results of our calculations.
So now to a visual analogy, and say I draw the line X: ______________________________
We can double or square the line, etc, and it will change it, but we must remember that what we are doing this too is actually a cube and the line is only representing that.
The same goes with the 2d's actually reprsenting four of them (or at least that is how I understand it ((I'm sure someone will correct me if I'm wrong)))
Hope that helps a little with the analogies.
Ask away...