1. ## Follow on Question for Max B's Another Gravity Question

I think this fits here.

As three dimensional creatures how would you percieve a four dimensional wind or flow? How about if it was traced with smoke or dye, lets, say so you could see it what would it look like? Would it look like it was all rushing at you from all directions? Or away? Both?

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4D, as in how a 3D flow of mass (wind, water, whatever) flows over time?

Towards/away/both depends on where you are in relation to the flow!

Typically, for both air and water, flows are most rapid at the center of a pipe, and the velocity is zero along the sides of a pipe. There's a logarithmic gradient between the walls.

Wind over the surface of the Earth follows a logarithmic gradient, as well, to a limited extent. The actual variance of wind from surface to altitude can vary significantly in both direction and velocity.

Can you be a little more specific, BigD, as to what you're trying to example?

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I think he asked what it looks like when a ghost farts. But I'm not sure...

4. I was reffering to four physical dimensions, as in a tesseract or a hypersphere. Though what a four dimensional cylinder would be called I have no clue.

But I guess what I'm asking is what would flow through a four dimensional pipe look like?

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I think you might be best off if you imagine helium-filled balloons floating
with the 4-dimensional breeze, and trying to figure out what they would
look like, or how they would behave. That way you have objects of
definite size and location to talk about. Easier to visualize, maybe.

-- Jeff, in Minneapolis

6. Originally Posted by Jeff Root
I think you might be best off if you imagine helium-filled balloons floating
with the 4-dimensional breeze, and trying to figure out what they would
look like, or how they would behave. That way you have objects of
definite size and location to talk about. Easier to visualize, maybe.

-- Jeff, in Minneapolis

What would helium balloons flowing through a four dimensional pipe seem to be doing to the man standing in the center of the flow?

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Originally Posted by BigDon
I was reffering to four physical dimensions, as in a tesseract or a hypersphere. Though what a four dimensional cylinder would be called I have no clue.

But I guess what I'm asking is what would flow through a four dimensional pipe look like?
I am a 3D being and have given this some thought.
First a lead up.Imagine what a 2D person would see if we moved things though 2 space.A cube would appear as a square or hexagon if twisted in 3 space.
The inside of a hollow cube would not be visible in 2 space.
A sphere is seen as a circle .The inside of this circle cannot be seen in 2 space.

A tessaract passing through through 3 space appears as a cube which can change shape if it is twisted in 4 space.
A hyperspere passing through 3 space appears as a tiny sphere enlarging to a larger sphere then back to a tiny then gone.

4D objects do not exist but 4 space does .

8. Thank you Undidly, so a 4-d tude would be in the "advanced class". I understand. Thank you for what you gave me.

9. This is more of a follow-up question to a follow-up question...

Suppose that there were two-dimensional creatures liiving on a two-dimensional strip in a three-dimensional world. Suppose there was a square with two-dimensional liquid in it. Wouldn't the liquid float out of the square into three-dimensional space?

So if there really is a fourth dimension, why don't our insides float away in a different direction?

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If the two-dimensional creatures and the two-dimensional square remain in
the two-dimensional strip, the two-dimensional liquid should, also, for the
same reason, whatever that reason is.

-- Jeff, in Minneapolis

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Originally Posted by BigDon
Thank you Undidly, so a 4-d dude would be in the "advanced class". I understand. Thank you for what you gave me.
"advanced class"?.Yes .What a view such a 4D person would have.Some believers say GOD is a 4D.

12. Originally Posted by Jeff Root
If the two-dimensional creatures and the two-dimensional square remain in
the two-dimensional strip, the two-dimensional liquid should, also, for the
same reason, whatever that reason is.
I suppose it's difficult to understand what reason might cause that to happen. I suppose retaining walls or something, but they'd have to be infinitely close together! What could possibly stop a two-dimensional strip to remain constrained? And extending that, what could cause a three-dimensional world to be constrained if there are really four or more dimensions?

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Cosmo-Glue.

14. here's a question: if a 3D guy can represent a 2D mobius strip with a 3D model, could a 4D guy place a REAL, 2D surface, mobius strip, on a bit of his 4D paper?

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Jens,

When I project an image of a photographic slide on a vertical screen, the
image doesn't fall off the screen because of gravity.

A three-dimensional layer of paint or ink can be thin enough that you might
consider it to be two-dimensional. It sticks to my ceiling fairly well...

Liquid crystals -- the stuff in liquid crystal displays -- are essentially liquid
in two directions and solid in a third direction. And the solid direction can
be just one molecule thick. Pretty close to a two-dimensional liquid.

Lay the two-dimensional strip on a horizontal three-dimensional tabletop.

How could a two-dimensional whatsit leave its two-dimensional strip?
You don't need to worry about how it will stay in the strip, you need to
worry about how to get it out of the strip and back in again.

The question, "How can a two-dimensional whatsit do such-and-such" is
generally answered, "There's no such thing as a two-dimensional whatsit."

-- Jeff, in Minneapolis

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Originally Posted by Jens
I suppose it's difficult to understand what reason might cause that to happen. I suppose retaining walls or something, but they'd have to be infinitely close together! What could possibly stop a two-dimensional strip to remain constrained? And extending that, what could cause a three-dimensional world to be constrained if there are really four or more dimensions?
A two dimensional being would not be able to get out of a circle if they were in a centrifuge and were getting a million G squashing them to the wall.They would be very flat,only 1 atom thick.
If the being and circle had any mass they may cause a depression in the centrifuge wall into which other nearby things in the centrifuge would fall.
The being may say that is gravity.

We are squashed into 3 dimensions by the spin of the 4D universe.
We can't get out of a hollow sphere.
A 4D being thinks we are in a sort of 3D circle.He can just step out of a closed 3D hollow sphere as we can from a circle.
We have mass and cause a dip in the wall (curved space time)into which nearby things fall.
We call it gravity.
Enough.I answered the question but some may say it is ATM.

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Originally Posted by undidly
Nope.
Originally Posted by undidly
but some may say it is ATM.
Yep.

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Originally Posted by Neverfly
Nope.

Yep.
Sorry.

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