This is the long-awaited 3rd segment of the “B Explains the Universe” series.

I’m sure most of you are aware that we live in a world with three standard dimensions – length, width, and height (or X, Y, and Z if you are a mathlete.) Less of you are probably aware that there is also a fourth dimension. No, it isn’t a wormhole in your clothes dryer in which socks escape from our reality. It’s much simpler than that. The fourth dimension is time. Time is a funny one because it relentlessly progresses in one direction. Lots of scientists say you can slow it down by traveling really fast – much faster than even I drive on the highway – close to the speed of light fast. But none of them has figured out a way to make it go backwards, though. Thank Bob for that one! I’d probably end up spending most of my days going back in time and slapping myself silly for something dumb I was about to do, and that would get tiresome for all of me.

Douglas Adams, a writer of humorous science fiction, has suggested several times that the fifth dimension is probability. I’d say there is a 50/50 chance he is right. Brian Cramer, another writer of humorous science fiction, has suggested that there is a seventh dimension, and it smells like old salmon. I think he is probably wrong about that one. Several other real scientists believe that there are as many as eleven dimensions, possibly more.

What I want to know is: where are these dimensions and why can’t we perceive them? Scientists like to explain this away by saying that some are too small to be detected or they loop back on themselves.  To me, they are just cheating to get the right answer. It’s like saying 6 x 9 = 42 … if you use base 13 instead of base 10 (our normal numbering system.)

So I was trying to picture what another physical dimension would be like, and of course I couldn’t. So I went backwards and tried to think of how a creature that could only perceive two dimensions would perceive our world, and what it would be missing. Here is what I came up with.

A two-dimensional viewpoint can be represented by a plane, a flat sheet. Imagine a clear sheet of something slicing through your living room, not really cutting it but simply merging with your stuff to draw your attention to just the objects it touches. Now imagine that you were a creature that could only see the part of your living room that the sheet is going through. You would see a slice of your couch, a slice of your TV, a slice of a chair or two. Inevitably though, there are objects in your living room that did not get “sliced” by the sheet. So, our creature is seeing some of what we see but in a different way, and it is also missing other things altogether.

Now, what if this creature could shift its universe over a tad along its unknown dimension? In other words, imagine the sheet slides over an inch or two. What it now sees will probably be similar to what it used to see. It will see a slice of your TV, a slice of your couch, a slice of a chair or two – but what it sees will also be subtly different – a slice of a different TV component, a different cushion of the couch, and maybe a chair leg pops into its world. If it moved its slice over a hundred feet, chances are that its world would look completely foreign.

Back in our world, if you really stretch your imagination you may be able to picture your world shifting in an unknown direction just a bit. Now, some things would be a little different; some new things would all of the sudden exist while others disappeared. If you shifted your world enough, it would probably become unrecognizable to you.

Now we can get a little supernatural with all of this. Say we live in one slice, and other people (or things) live in a slice right beside ours. Maybe once in a while there is some bleed-over. Maybe once in a while one of them somehow puts his elbow over the line, or even pops in and back out of our slice. Perhaps that is the phenomena of ghosts? Maybe ghosts are not dead souls roaming around, but simply our dimensional neighbors who sometimes like to borrow our space.

If you can draw any conclusion from this thought experiment, it’s probably this: If there really are other dimensions out there, chances are that there is a whole lot to the universe that we are missing, and therefore virtually everything we know and believe to be true is probably wrong.