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Visualizing the Fourth Dimension Using Color (rdrop.com)
60 points by zkz on July 16, 2009 | hide | past | web | favorite | 13 comments

Actually you can further extend color. Color it self is on a 3 dimensional space (RGB). Now you have 6 dimensions to play with. Although in practice I found that doing Brightness and (Red/Blue) is a good way.

If you are doing points on a multi dimensional space, you can start using various shapes (Length, Width, Height) or Number of faces. Alternatively you can also do stars with spikes coming out (more spikes per higher value), I find this the easiest to visualize rather than shape sizes.

I always preferred the blunt "pull this part back to yesterday, when the knot wasn't, move it over here, bring it back to today, and it's unknotted" argument.

That's treating the 4th dimension as time, which is fine, but this article is referring specifically to the 4th spatial dimension. Sometimes pop physics type articles confusingly refer to the 4th spatial dimension as the 5th dimension.

One might just as easily say that it's treating time as a 4th spatial dimension (offering a further 2 degrees of freedom, when our actual experience of time seems to be sadly one way, unless you read pravda). What he's suggesting is not substantively different from the color analogy.

What exactly is the 4th spacial dimension? Since we only experience space in three dimensions, how can we assign meaning to a fourth dimension in space?

The classic Flatland also helps. http://www.geom.uiuc.edu/~banchoff/Flatland/

There are only three spatial dimensions, and time.

If you are going to play tricks using color, you may as well use flavors and odors for a sixth dimension visualization (and any other property you may think of for further extending dimensions).

I call bullshit.

It's important to realize that this is mathematics not physics.

This might give you an idea of what they can be used for: http://en.wikipedia.org/wiki/Level_set_method

Please forgive my simplistic questions, I do not have any higher education in physics and in my reading of pop science magazines I doubtless remain ignorant of important developments.

What is the proof that there are only three spatial dimensions?

You say "three spatial dimensions and time." Is time a dimension just like the spatial ones but we perceive it differently? Or is time something other than a dimension? And when was this proved or demonstrated?

You can't prove there aren't more dimensions. After all you could be hiding them in your garage with your invisible dragon or you could of rolled them up in a Calabi-Yau manifold.

Time is a unidirectional so it's considered to be a different kind of dimension than the spacial (bidirectional) dimensions.

.. Although depending on the particle theory you subscribe to, it may only be unidirectional to us (positrons being electrons moving backwards in time, etc.)

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