Originally published at: https://boingboing.net/2019/10/17/what-the-hell-is-a-dimension.html

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# What the hell is a "dimension" anyway?

I always count time - for Four Dimensions, and then am frustrated I can only go one direction in the time dimension.

I don’t even understand why space itself exists, let alone all the stuff inside of it.

it exists so the stuff inside it has some place to be.

Remember “Imagining the Tenth Dimension” ?

Consensus seems to be that this guy has no idea what he’s talking about, but it’s a neat little yarn for what it is.

The other day I was walking my dog and trying to imagine if we had 2 dimensions of time.

Pedantry warning for all that follows

I really wish he’d been explicit, at least for the college students and up, about the fact that he’s specifically talking about spatial or spacetime dimensions, because that is not how physics or math or even statistics uses the term. Otherwise my first semester quantum mechanics textbooks wouldn’t talk about infinite dimensional Hilbert spaces, and the immunology lab I interned in as a high school senior wouldn’t have taught me about parsing and analyzing six dimensional data sets.

Also, when you start looking at holographic principles and entanglement explanations of spacetime based on decoherence, it turns out physicists aren’t quite in agreement about how many *large* spacetime dimensions there are, which at least suggests that *something* is off with the three-right-angles explanation although I admit I don’t really know what.

Yeah, if the point of the video was to clarify specifically what “dimensions” are, he started to go off course with the later bits. Like, he talks to the grad student about dimensions being “small”, and I understand he’s speaking informally, but I thought that confusion between a *dimension* and a *place* is the kind of thing he was meant to be clearing up. It seemed like he was more about advertising the “gosh woo how inscrutable” branding of physics towards the end.

IMO the problem is that we speak of dimensions as *things,* as if each “dimension” could have its own properties, rather than speaking of *dimensionality,* as in, the number of independent variables required to uniquely specify a single value of a property (such as position). Space is three-dimensional because if you use fewer than three numbers to specify position, then you get the same value for different positions; and if you use more than three numbers, then some of those numbers will be redundant because they could be calculated solely from the first three numbers.

That is a good example! The whole point of relativity is that there is no “the” time dimension, but it is confusing to express because of our habit of saying “dimension” when we mean “axis”. The video does touch on this in the part with the cute but dumb college student – when two people are moving at different speeds, their “time” “axes” *don’t* point in the same direction.

Oh Wow! That is crazy pants.

I was just (at the time) thinking about Flatland and what if we applied that metaphor to time (not spacetime) instead of spacial dimensions. How we experience time is a bit how Flatlander’s experience 3D objects intersecting their 2D space. But I’m not peddling any woo marshmallow theories. Just walking off some edibles.

I got lost half-way in… Damn…

TIME CUUUBE

Insofar as it’s possible to make sense of anything on that site, it seems like the author one day grokked the concept of time zones and believed this was some kind of new revelation which nobody else understood. Mixed up with a generous dash of Dr Bronner’s Castile Soap.

Yes, I got that vibe right away.

Quite true.

But using more dimensions at different angles may be more informative and lead to more accurate models than using the minimum 3d x 90° Cartesian grid.

R. Buckminster Fuller, f’rex, suggests using a 6d x 60° grid to construct a model where every cell adjacent to a central cell has the same distance and angular relationship to both the central cell and its immediate neighbors.

The latter grid can do a much better job of mapping omnidirectional energy vectors in omnidirectional space without distortion introduced by the often-arbitrary orientation of the XYZ axes.

Contrast this to the 3d x 90° Cartesian grid, where surrounding a cubical central cell with one layer of additional cells results in a larger cube where the distances to each adjacent cell vary, depending on whether they are in the corner, edge, or side of the expanding cubical shell

This is why Bucky likes to call the resulting cell shape (technically a cuboctahedron) the “vector equilibrium,” and a grid of such cells the “isotropic vector matrix.”

NB: This is *only* about remapping conventional “threespace” with a different grid. No exotic “six-d” space is implied. It’s just a different map grid applied to the same “3d” space we’re familiar with.

Also to give time something to expand into (and bring light with it)…