1524: Dimensions

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I would say time is definitely one of my top three favorite dimensions.
Title text: I would say time is definitely one of my top three favorite dimensions.


Ambox notice.png This explanation may be incomplete or incorrect: Too much like a discussion. Needs a rewrite.
If you can address this issue, please edit the page! Thanks.

Our world is 3-dimensional (like in a box; length, width and height.) But in modern physics, space and time are unified in a four-dimensional continuum called spacetime where time becomes the fourth dimension.

It is to this 4-dimensional spacetime that Cueball refers in his monologue to Megan, while he is philosophizing about his life in these four dimensions.

What Cueball comments on is that whereas we can, to some extent, determine in which direction we wish to move (at least on the surface of the Earth) in the three dimensions of space (up-down, left-right, forward-backward), we cannot help but being pushed inexorably forward through time. So it is quite lucky for Cueball that he thinks this is OK.

Being pushed constantly in one of the other directions would very soon be lethal. Suddenly if you where pushed over a cliff or in front of a truck, or also if you were pushed hard enough against a rock. But even if you avoided any of these you would die soon enough if it was some constant direction, because then you would soon leave the Earth if you travel in a tangent to the surface, as the Earth is approximately spherical. (see 1376: Jump especially the title text). Also because of all the movements the Earth undergoes, (spinning and orbiting the sun, that orbits the galaxy that moves toward Andromeda) we are already constantly being pushed in several directions at once, without realizing it. But it is always changing directions, as opposed to times, which we always move forward through.

Moving forward in time will also eventually be lethal by causing old age. It also may place you in dangerous times when natural or man-made disasters have happened (or placing you in the path of a moving truck), but it is only possible to avoid these dangers by sidestepping them in one of the three spatial dimensions.

In the title text Cueball then continues to muse about his favorite dimensions and places time in his top three dimensions. This initially seems to mean that one of the three space dimensions must be his least favorite. But since in space there is no difference between the three dimensions, it's not obvious why any one would be preferred over another. And if that was the case, then time would have to be his favorite dimension. (Radial and cylindrical coordinate systems describe 3d worlds with vastly differing dimensionalities)

There are, though, a couple of other ways to think about this:

(1) Cueball could be referring to a naive view of three spatial dimensions in a fixed reference system (like on earth), where the three directions can be different. In a Cartesian coordinate system, as often seen in geometry textbooks, two axes form a horizontal plane and the third axis is the vertical one. In this case, perhaps his two other top three "dimensions" could be those in the plane (along the surface of the Earth) as he could easily move along these two axes, but moving along the third axis (e.g. flying away from ground - or falling down a cliff) requires special arrangements or is outright dangerous.

(2) If Cueball is not supposed to represent a real person (like for instance Randall himself, as he often does in this type of comic) then he may be viewed as a "real" comic strip character, thus always living in a two dimensional world. This view offers another explanation, which may be that since he only exists in two spatial dimensions, these are his "favorite" ones along with time (or "movement" from panel to panel, see wired comic mentioned below), with the third spatial dimension being outside his experience. Since Cueball specifically mentions the four dimensions in the comic, and makes it clear that he could have been pushed through any of them (but has been subject only to a push through time), this may not be such a likely explanation.

In M-theory, a theory that unifies all consistent versions of superstring theory, spacetime is eleven-dimensional, which would make a place in the top three a somewhat more interesting position. However, these extra dimensions are not currently detectable.

Interestingly, Randall has already, back in the December 2014 issue of Wired magazine, published the xkcd guide to dimensions where the main part of this comic was already used in panel 9 out of 20. This issue of Wired magazine was about multiple dimensions, and Randall's section is about imagining higher dimension. The article is a mix of xkcd-style comics and captions explaining them. The panel in question show Cueball saying, "Of all the dimensions I could have spent my life being pushed inexorably through, I guess "time" isn't the worst." (the only difference being that "all the" has been changed to "the four" in this comic). In panel 15 of the Wired comic series, Randall considers how dimensions can be represented in a two-dimensional comic strip: a character moving within a panel represents movement in space but movement from panel to panel represents movement in time.

Previously Randall has made a comic about a man who was pushed sideways (although that was by the gravity which affected him wrongly) - so he was pushed both through time and fell sideways: 417: The Man Who Fell Sideways.


[Cueball is sitting up against a tree, Megan lies with her hands behind her neck in front him under the foliage of the tree.]
Cueball: Of the four dimensions I could have spent my life being pushed inexorably forward through, I guess "time" isn't the worst.

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This almost seems to be making fun of the frivolity with which people discuss the existence of multiple dimensions without realizing what that actually means. Anyone else get that feeling?

Reminds me of http://xkcd.com/417/ and http://en.wikipedia.org/wiki/Patema_Inverted which make fun of dimensions too. (talk) (please sign your comments with ~~~~)

Great - I will add 417. please sign you comment with --~~~~ ;-) --Kynde (talk) 07:57, 13 May 2015 (UTC)

My first thought about Title Text was that moving sideways (standard x or y axis) would be bad, but not as bad as moving upwards (standard z axis). Z direction would be my least favourite! -- 08:20, 13 May 2015 (UTC)

You're thinking that from an incredibly geo-centric point of view. There is no reason that the three axes would be defined in absolute terms in terms of the surface of the Earth. Indeed, even if we *did* choose to define the three spacial dimensions relative to something to do with Earth, it would seem logical to me that the best way to do that would be to define the X-Y plane as the plane of Earth's orbit around the Sun. In that case, unless you happened to be located at 23.5 degrees latitude, travelling in the Z direction would *not* be travelling perpendicular to the surface of the Earth, which is presumably to what you were referring in your comment. --Zagorath (talk) 22:38, 15 May 2015 (UTC)
I think you guys are vastly overthinking the title text. Randall is making a joke. The 4 dimensions discussed are Length, Width, Height and Time. if you pick three of them to like, and one to hate, Width is the obvious hate. Most men like the idea of being taller and "longer where it counts". Being overweight is something most people dont like. 15:41, 29 May 2015 (UTC)

The explanation looks more and more like a discussion. Four dimensions or eleven? I see that string theory "predicts 10 or 26 dimensions" (http://en.wikipedia.org/wiki/Spacetime). I think someone (but not me) should rewrite the discussion in a more comprehensive way.Jkrstrt (talk) 08:35, 13 May 2015 (UTC)

We might had a link to the 2 what-if related to move steadlily in one direction : http://what-if.xkcd.com/135/ and http://what-if.xkcd.com/64/ (talk) (please sign your comments with ~~~~)

Isn't the alt text a reference to the fact that a cartoon only has two physical dimensions? That's how time can be in his top three. 09:09, 13 May 2015 (UTC)

"Being pushed in one of the other directions could be lethal, if you where pushed hard enough against a rock, over a cliff or in front of a truck..." Being pushed in the dimension of time is also ultimately fatal though. Push someone through time for long enough and they'll certainly die. 09:20, 13 May 2015 (UTC)

Why the hang up on fixed coordinate systems even though there isn't even a practical way to establish one. (To the best of my knowledge distance can only be measured relative to some object.) it's more likely that the top three dimensions would be along the lines of North/South, East/West and time which is a much more practical point of view.-- 11:32, 13 May 2015 (UTC)

So if it is in the top three out of four, it must be number one.... I don't agree. What if Randall would hate going to Zazane galaxy or Ottzello galaxy (X axis), but wouldn't mind going to Xanthrus spiral or Rizoku galazy (Y axis) [1]. 13:50, 13 May 2015 (UTC)

The argument would be that this is an arbitrary/anthropocentric classification of X, Y and Z that the universe neither confirms nor denies as the 'true' direction of the three dimensions (which can be in any direction, so long as each is perpendicular to the two others, in a Euclidean sense).
(And personally. as opposed to the current description. I tend to think of x/y as the horizontal plane and z as vertical motion (up or down, depending on utility), in everyday use, although I'm flexible and will subscribe to one or other standard (and handedness of unit directions!) when dealing with other modelling systems. It's all easily convertible-between.) 17:31, 13 May 2015 (UTC)

I was going to say that if we think of three dimensions simplistically as length-width-height, it might make sense for someone to have a least-favorite spatial dimension--maybe width, since we're always fighting increases in that one. But, I REALLY like the idea above that time would be in the "top three" dimensions for a TWO-dimensional comic-strip character! (Note that Randall plays with this in the Wired comic series linked above, noting that in a comic strip, a small movemement indicates movement through space, but a large one--like between panels--indicates time: see panel #15 in the series) Clever and Randall-esque idea!! I suggest adding this idea to the main text and taking out some of the other discussion around this point.Jv (talk) 16:32, 13 May 2015 (UTC)

Could it be that the title text is purely playing with words, as in any list of length n (4 dimensions in the world of the comic), one can only have n-1 favourites, so Cueball can only have a top / favourite 3? Mb (talk) 20:06, 13 May 2015 (UTC)

"Moving forward in time will also eventually be lethal by causing old age, ... But it is only possible to avoid these dangers by sidestepping them in one of the three spatial dimensions." - Wait! I can sidestep death? AWESOME! Djbrasier (talk) 20:09, 13 May 2015 (UTC)

The explanation says his favourite co-ords could still be x,y and z. Shouldn't that really by r, phi, theta since that's the best system for a spherical Earth? Also, I don't think you need to mention special relativity, even in classical physics you consider time to be the fourth dimension, you just lack a co-ordinate transformation between space and time. 15:22, 13 May 2015 (UTC)

Does the statement: “pushed inexorably forward through time” not strike anyone as important to discuss and explain? A book by Dan Falk describes the ramifications were one able to move volitionally through time: http://tinyurl.com/l2btjfd.

The Greeks held that time flowed like a river through the present from the past. Others (?) suggest that time flowed from the future into the present. Randall poses that we are pushed forward through time. Who or what does the pushing? With what purpose? To what end?

Pushing suggests we’re unwilling to go forward. But so does pulling. Pulling, by the way, might imply gravitational forces at work. However, those almost never end well. Run, you clever boy (talk) 14:30, 14 May 2015 (UTC)


I was surprised nobody mentioned Randall's most famous comic about Time (which this comic reminded me of a little bit). WhiteDragon (talk) 23:30, 14 May 2015 (UTC)

I do not see any relation with a comic about something that occurs in the far future, and is also called time because it is dynamic and ran over an extended period of time... --Kynde (talk) 19:51, 17 May 2015 (UTC)

I love how the title text seems to imply that Randall has a least favorite space-dimension. The three space dimensions are arbitrarily assigned (they are orthogonal to each other but not absolute in relation to anything) so it's like he has a grudge against a completely arbitrary direction. 03:20, 15 May 2015 (UTC)

Black Hole

I wonder nobody came up yet with the obvious interpretation. The only situation where one is forced along a space dimension in the same sense as along time (everything else being unphysical - when you "just" fall from a cliff, you still could be saved) would be falling into a Black Hole. Which is indeed somewhat inconvenient :-) 12:52, 16 May 2015 (UTC)

I see no relation to black-holes. It is very far fetched from this mundane situation. UNtil you actually enter the event horizon you cold still be saved, and after that we really do not know what happens (except that you will probably be dead before you reach this horizon). --Kynde (talk) 19:51, 17 May 2015 (UTC)

Could the alt text be referring to hologram theory? My understanding of that is that the universe might only have two actual dimensions describing three dimensions in its interactions. 07:00, 25 May 2015 (UTC)

If I were to read the current explanation without teading the comic, I would have no idea that this comic is partially a joke- the idea thay we would instead be pushed inexorably sideways or something is a source of humor in this comic. Bbruzzo (talk) 13:50, 30 August 2015 (UTC)

I agree totally. The main point of this comic is the funny idea of being pushed inexorably through a spatial dimension (like in the Man Who Fell Sideways). That's clearly the funny part of this comic.DenverCoder9 (talk) 05:49, 16 December 2015 (UTC)
I thought this too: that the person would be able to time travel at will, but would have the inconvenience of travelling through space in a certain dimension. Also, nobody thought that the least favourite dimension could be Z, as in afraid of heights (assuming XY as the surface of Earth and Z as altitude)? 22:38, 22 December 2015 (UTC)

The title text, in my interpretation, is a sort of logic puzzle which implies that time must be his favorite dimension. Since the three spatial dimensions are degenerate, the fact that it's not his 4th favorite implies it must be his first. Also, main point: it is also just funny because 1. the idea of having a favorite dimension and 2. the application of "top three" to a group of 4 things, three of which are indistinguishable. DenverCoder9 (talk) 05:49, 16 December 2015 (UTC)