What if the universe is a four-dimensional ball?

[Condog]

W?

I'm confused about what you think your question means.

He's asking where the fourth point on a Cartesian coordinate plane of four dimensions would go. As far as i can tell, it would go in a direction we can't see, because we only perceive three dimensions.

[DemonzLunchBreak]

W?

I'm confused about what you think your question means.

He's asking where the fourth point on a Cartesian coordinate plane of four dimensions would go. As far as i can tell, it would go in a direction we can't see, because we only perceive three dimensions.

That's a silly question, then.

[Yoshimo]

I've managed to find four lines placed so that they all have right angles to each other, may be wrong, very hard to visualise.

Imagine two square pyramids. All sides are right triangles, where the two edges that aren't the hypotenuse are the same length. Make another, directly on top, upside down, so that they seem to be twice as long now. Make all lines into infinates and take away the base, and you have some 4d-ish Axises, X,Y,Z,W.

Don't nag me on this, it is very hard to visualise, I'm telling you right here and now.

[Topo]

...Finding even one consistent holographic description, a priori, seems like a long-shot, because it would be a disembodied nonlocal description of quantum gravity. In string theory, not only is there one such description, there are several different ones, each describing fluctuations of horizons with different charges and dimensions, and all of them logically fit together. So the same physical objects and interactions can be described by the fluctuations of one-dimensional black hole horizons, or by three-dimensional horizons, or by zero-dimensional horizons. The fact that these different descriptions describe the same physics is overwhelming evidence that string theory is consistent...

This is a quotation from the overview of string theory on Wikipedia.
It takes people years to understand this shit. I mean, I only understand up to what we learned in AP chem, and that's crazy enough for me. I started getting lost after the double slit experiments.
I tried to think about what a 4-dimensional ball looks like, and guess what, it looks like this:

Not surprisingly, that it not what I expected!

Higher level physics =/= simple or intuitive.

[lord_day]

A four dimensional 'sphere' or hypersphere that passes through our three dimensional plane would look like a tiny sphere that keeps growing, then after a bit it starts shrinking, then it disappears. The image that you have used Topo is just a projection of a hypersphere, in the same way that a sphere can be projected onto a piece of paper.

[Topo]

That's interesting actually. I thought the same thing. I suppose the representation of the hyper sphere is just a lot more complicated than the hyper sphere itself. My bizzle.