## Naming the Dimensions and Directions

Ideas involving the use of more than three spatial dimensions. If you want to talk about spacetime go to the Time Dimensions forum instead!

### Naming the Dimensions and Directions

I would like to suggest that we get ready to explore any number of higher dimensional universes by establishing a simple naming convention, using Greek prefixes as the basis of the names of the dimensions and the left-right directions in each dimension.

For example, the Greek prefixes for four, five and six are tetra, penta and hexa. To keep it simple, we would name each dimension according to the Greek prefix. The first three dimensions are height, length, and width, with the directions up-down, forward-backward, and left-right. We say how high, long, and wide an object is.

The fourth, fifth and sixth dimensions would be tetrath, pentath and hexath. The "-th" ending makes it a noun. The directions are leetetra-rytetra, leepenta-rypenta, and leehexa-ryhexa. The prefixes "lee-" and "ry-" obviously correspond to "left" and "right." We say how tetra, penta and hexa and object is.

A six-dimensional box could be 1 foot high, 2 feet long, 3 feet wide, 4 feet tetra, 5 feet penta, and 6 feet hexa. What is its pentath? Five feet. Your 6D roadmap might tell you to "turn leetetra at Dixon and Billings, go two blocks, turn ryhexa at Fernwell." If that is a full 6D intersection and you're on Billings, you'd have a choice of going straight, turning left or right onto Casey, leetetra or rytetra onto Delaware, leepenta or rypenta onto Everbrook, or leehexa or ryhexa onto Fernwell. Your 6D road would be only a 5D surface, so you wouldn't turn "up" or "down."

The list of Greek prefixes is as follows:
1 - hen, 2 - di, 3 - tri, 4 - tetra, 5 - penta, 6 - hexa, 7 - hepta, 8 - octa, 9 - ennea, 10 - deca, 11 - hendeca, 12 - dodeca, 13 - triskaideca, 14 - tetrakaideca, 15 - pentakaideca, 16 - hexakaideca, 17 - heptakaideca, 18 - octakaideca, 19 - enneakaideca, 20 - icosa, 30 - triaconta, 40 - tetraconta, 50 - pentaconta, 60 - hexaconta, 70 - heptaconta, 80 - octaconta, 90 - enneaconta, 100 - hecatont, 200 - diacosioi, 300 - triacosioi, 400 - tetracosioi, 500 - pentacosioi, 600 - hexacosioi, 700 - heptacosioi, 800 - octacosioi, 900 - enneacosioi, 1,000 - chili, 10,000 - myria.

Who's for going to the heptacosioi tetrakaideca universe for coffee? Bring a 500 PW flashlight. It's real dark.
Pentoon
Mononian

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### Re: Naming the Dimensions and Directions

Yes, because this is very legible, intuitive, and just rolls off the tongue... (/sarcasm)

4+D directions wouldn't tell you to turn like that, though. If they used full directional steering, then you have an infinite range of directions to turn in, rather than just left and right, so there's no point making up words for them. If they limit directions to one dimension (like I've suggested in my topic on 4D cars), you'd just use left and right still.

If we really need to refer to specific higher dimensions we can just use a number, there's no need for writing out Greek prefixes. You can easily refer to the n-D length of an object.

Keiji

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Location: Torquay, England

### Re: Naming the Dimensions and Directions

I really struggle to see what people find so difficult here. You just can't fix the across-directions in anything higher than three dimensions.

Here's a little exercise to do. You take four dimensions, and remove height (up/down), which gives three dimensions. You next remove forward/backwards, which is based on motion. You get the 'across' space, which is N-2 dimensions. This is the same as a floor in 3d.

Now grab something like a handful of clocks, and lie them out on the floor. The clocks have to point to the roof, so you can't turn them face-down. But not with standing, you can put the clocks so that the 12-position points anywhere. Now these all represent 4d people, who are standing against the wall, facing into the room (like wall-flowers at a dance). But one can't say anything except that there is 'clockwise' or 'anticlockwise'. There's no 'left' or 'right'.

If you do the same thing with 3d, you remove height and forward, and you get one dimension. Your wall-flowers are strung out in a line, with a conventional 'left' and 'right'.
The dream you dream alone is only a dream
the dream we dream together is reality.

wendy
Pentonian

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