1524: "Dimensions"

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1524: "Dimensions"

Postby karhell » Wed May 13, 2015 6:50 am UTC

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


Agreed, Randall, Time is also one of my top three favorite dimensions ^^
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Re: 1524: "Dimensions"

Postby mikrit » Wed May 13, 2015 7:00 am UTC

Of the fifteen hundred and twentyfour xkcd comics I could have spent four months of my life being pushed inexorably forward through, I guess 1190: Time isn't the worst.
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Re: 1524: "Dimensions"

Postby yahiek » Wed May 13, 2015 7:05 am UTC

Seemed like a reference to https://xkcd.com/417/ to me.

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Re: 1524: "Dimensions"

Postby bachaddict » Wed May 13, 2015 7:39 am UTC

yahiek wrote:Seemed like a reference to https://xkcd.com/417/ to me.

I don't think it's a direct reference. Just produced by the same mind.

Why am I getting deja vu reading the comic? I feel like I've seen one of the concepts before, like time travel or something.
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Re: 1524: "Dimensions"

Postby Envelope Generator » Wed May 13, 2015 7:46 am UTC

karhell wrote:Agreed, Randall, Time is also one of my top three favorite dimensions ^^


May I ask you if you've considered all the possibilities that "down" might offer you?
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Re: 1524: "Dimensions"

Postby Quercus » Wed May 13, 2015 7:55 am UTC

bachaddict wrote:Why am I getting deja vu reading the comic? I feel like I've seen one of the concepts before, like time travel or something.


Possibly https://xkcd.com/209/?

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Re: 1524: "Dimensions"

Postby YellowYeti » Wed May 13, 2015 8:08 am UTC

Considering my waistline, time isn't the only dimension I am being pushed inexorably forward through :(

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Re: 1524: "Dimensions"

Postby CharlieP » Wed May 13, 2015 8:20 am UTC

(Veering off-topic)

Several years ago I tried "inventing" a variant on noughts-and-crosses, played in four dimensions. From (hazy) memory it had a 3x3 grid of the usual 3x3 grid, so "lines" could be completed horizontally, vertically or diagonally on a single grid, by using the same cell position in grids in a horizontal, vertical or diagonal line, or (I think) a combination of both. So if putting a cross in the centre cell of the grids in the top row could be considered analogous to completing a "vertical" line, it follows that putting a cross in the centre cell of the grids in the left column would be a fourth dimension.

I tried running it past a friend.

"But the fourth dimension is time!"

"No, in this particular game there are four dimensions, drawn in 2D".

"But the fourth dimension is time!"

"Popularly, yes. But in the context of this game I'm using four directional dimensions, to make it more interesting".

"But the fourth dimension is time!"

I gave up on the concept.
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Re: 1524: "Dimensions"

Postby Flumble » Wed May 13, 2015 8:26 am UTC

Time is the stupidest dimension ever conceived. It's like "ooh, we have one dimension, let's add one orthogonal to it and let's add one orthogonal to both" and then "let's add one dimension that allows processes to take place, so that we can evaluate the everything linearly* from a starting vector". Well fuck you, universe. Next time make it 4 space dimensions, or at least 4 space+1 time.
I should throw this in.

*though I bet it's O(t!) in time, going by the many-worlds interpretation.

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Re: 1524: "Dimensions"

Postby niauropsaka » Wed May 13, 2015 8:27 am UTC

Do other dimensions even have names?

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Re: 1524: "Dimensions"

Postby Envelope Generator » Wed May 13, 2015 8:44 am UTC

Yes, they are up-down, left-right and A-B.
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Re: 1524: "Dimensions"

Postby JDGA » Wed May 13, 2015 8:47 am UTC

Seemed more like a reference to these two What-Ifs to me.

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Re: 1524: "Dimensions"

Postby orthogon » Wed May 13, 2015 8:47 am UTC

Flumble wrote:Time is the stupidest dimension ever conceived. It's like "ooh, we have one dimension, let's add one orthogonal to it and let's add one orthogonal to both" and then "let's add one dimension that allows processes to take place, so that we can evaluate the everything linearly* from a starting vector". Well fuck you, universe. Next time make it 4 space dimensions, or at least 4 space+1 time.

Wow. I've spent the last few days venting against the British electorate, when I could have being railing against the very structure of spacetime itself (with about as much effect).

As I understand it, time has almost the same relationship with the other dimensions as they have with each other, except that some joker slipped a factor of i in there. But things would be pretty boring if all the dimensions were spacelike, wouldn't it? A null cone would be a single zero-sized event and nothing would be able to interact with anything else. (Physicists, please correct me).
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Re: 1524: "Dimensions"

Postby CharlieP » Wed May 13, 2015 9:10 am UTC

orthogon wrote:Wow. I've spent the last few days venting against the British electorate


Half the country seems to have spent the last few days venting against the British electorate. After spending the months leading up to the actual election saying pretty much sod all.
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Re: 1524: "Dimensions"

Postby da Doctah » Wed May 13, 2015 9:59 am UTC

niauropsaka wrote:Do other dimensions even have names?

    Marilyn McCoo
    Billy Davis, Jr.
    Florence LaRue
    Lamonte McLemore
    Ron Townson

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Re: 1524: "Dimensions"

Postby area » Wed May 13, 2015 10:13 am UTC

bachaddict wrote:Why am I getting deja vu reading the comic? I feel like I've seen one of the concepts before, like time travel or something.


I have definitely read or heard this text before, and I can't remember where. It's driving me sufficiently nuts that I dusted off this forum account in the hopes of someone putting me out of my misery.

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Re: 1524: "Dimensions"

Postby brenok » Wed May 13, 2015 10:13 am UTC

niauropsaka wrote:Do other dimensions even have names?

Water, South and Nuclear holocaust

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Re: 1524: "Dimensions"

Postby SpaceDetective » Wed May 13, 2015 11:39 am UTC

area wrote:I have definitely read or heard this text before, and I can't remember where. It's driving me sufficiently nuts that I dusted off this forum account in the hopes of someone putting me out of my misery.


I've seen this exact text before in a deleted 2012 tweet by BeeStapler.

I can't post links here yet, but there's bit more info on this comic's reddit thread in /r/xkcd.

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Re: 1524: "Dimensions"

Postby The Moomin » Wed May 13, 2015 12:06 pm UTC

niauropsaka wrote:Do other dimensions even have names?


During my maths degree, one of the tutors mentioned "the nth dimension of porridge".

I can't decide whether being pushed through porridge would be soothing or horrific.
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Re: 1524: "Dimensions"

Postby solune » Wed May 13, 2015 12:24 pm UTC

I can't believe nobody has posted their own favourite dimensions yet. Well here's mine

1) North-South
2) Up-Down
3) Time
4) East-West
5,6 and more) the N-Brane that best describes the Higgs Boson

I feel justified in using a terrestrial reference frame to name my coordinates. Would anyone of you argue that I should use Port/Starboard and Forward/Back ?

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Re: 1524: "Dimensions"

Postby pkcommando » Wed May 13, 2015 12:31 pm UTC

I think a dimension changed its name to Mike. He got sick of the condescending attitudes of people thinking they could just assign him a name like he was their property and would be bound to that name forever. So he went down to the courthouse and got his name legally changed to Mike.

I don't remember which dimension did this, though. And I've heard he's now getting bored with it and is seriously considering changing it to The Dimension Formerly Known As Mike.

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Re: 1524: "Dimensions"

Postby ggh » Wed May 13, 2015 1:11 pm UTC

area wrote:
bachaddict wrote:Why am I getting deja vu reading the comic? I feel like I've seen one of the concepts before, like time travel or something.


I have definitely read or heard this text before, and I can't remember where. It's driving me sufficiently nuts that I dusted off this forum account in the hopes of someone putting me out of my misery.

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Re: 1524: "Dimensions"

Postby rmsgrey » Wed May 13, 2015 1:17 pm UTC

CharlieP wrote:(Veering off-topic)

Several years ago I tried "inventing" a variant on noughts-and-crosses, played in four dimensions. From (hazy) memory it had a 3x3 grid of the usual 3x3 grid, so "lines" could be completed horizontally, vertically or diagonally on a single grid, by using the same cell position in grids in a horizontal, vertical or diagonal line, or (I think) a combination of both. So if putting a cross in the centre cell of the grids in the top row could be considered analogous to completing a "vertical" line, it follows that putting a cross in the centre cell of the grids in the left column would be a fourth dimension.

I tried running it past a friend.

"But the fourth dimension is time!"

"No, in this particular game there are four dimensions, drawn in 2D".

"But the fourth dimension is time!"

"Popularly, yes. But in the context of this game I'm using four directional dimensions, to make it more interesting".

"But the fourth dimension is time!"

I gave up on the concept.


I got bored with it once I showed it was a trivial first player win and moved on to 4x4x4 instead.

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Re: 1524: "Dimensions"

Postby Keyman » Wed May 13, 2015 1:58 pm UTC

So here I sit, on Wednesday morning, with a crapload of work on my desk, and 8 xkcd tabs open in my browser.

Thanks guys!!! :D
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Re: 1524: "Dimensions"

Postby wayne » Wed May 13, 2015 2:10 pm UTC

rmsgrey wrote:
CharlieP wrote:(Veering off-topic)

Several years ago I tried "inventing" a variant on noughts-and-crosses, played in four dimensions. From (hazy) memory it had a 3x3 grid of the usual 3x3 grid, so "lines" could be completed horizontally, vertically or diagonally on a single grid, by using the same cell position in grids in a horizontal, vertical or diagonal line, or (I think) a combination of both. So if putting a cross in the centre cell of the grids in the top row could be considered analogous to completing a "vertical" line, it follows that putting a cross in the centre cell of the grids in the left column would be a fourth dimension.

I tried running it past a friend.

"But the fourth dimension is time!"

"No, in this particular game there are four dimensions, drawn in 2D".

"But the fourth dimension is time!"

"Popularly, yes. But in the context of this game I'm using four directional dimensions, to make it more interesting".

"But the fourth dimension is time!"

I gave up on the concept.


I got bored with it once I showed it was a trivial first player win and moved on to 4x4x4 instead.


I did the same thing in high school, 20+ years ago. I tried a 5x5x5, but it wasn't as much fun.
But then, I don't care for the larger Rubik's cubes, either. Once you know the concept, just sitting there twisting a cube around gets old, fast.
Some games actually get easier when you go big. They give more room to compensate for errors.

Maybe a 5x5x5x5 game would be more interesting. It might be that tic-tac-toe needs to be a grid of (D + 1) ^ (D - 1) Where D = dimensions used for play.
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Re: 1524: "Dimensions"

Postby Jackpot777 » Wed May 13, 2015 3:37 pm UTC

da Doctah wrote:
niauropsaka wrote:Do other dimensions even have names?

    Marilyn McCoo
    Billy Davis, Jr.
    Florence LaRue
    Lamonte McLemore
    Ron Townson


Florence LaRue is very small and is folded into Ron Townson. They live in an apartment hypercube together, but never both at the same time.

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Re: 1524: "Dimensions"

Postby Angelastic » Wed May 13, 2015 3:51 pm UTC

This also reminds me of What Ifs 64 and 135.
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Re: 1524: "Dimensions"

Postby azule » Wed May 13, 2015 4:18 pm UTC

ggh wrote:
Spoiler:
area wrote:
bachaddict wrote:Why am I getting deja vu reading the comic? I feel like I've seen one of the concepts before, like time travel or something.


I have definitely read or heard this text before, and I can't remember where. It's driving me sufficiently nuts that I dusted off this forum account in the hopes of someone putting me out of my misery.

Frame 9 of 20

This is what she linked to: Image,
same (full size) image in a spoiler:
Spoiler:
Image


ggh is the man! I also had a small feeling a familiarity with this comic's concept, but to find out that it's exact-FUCKING-ly the same???!!! Well, thanks for drawing a picture for it, Randall! hah!! Now get on to including some Beanish into a new comic as you contemplated doing long ago! Exclamation points!!!!1
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Re: 1524: "Dimensions"

Postby senor_cardgage » Wed May 13, 2015 4:24 pm UTC

Every time someone hides title text in a spoiler tag, an angel loses its wings.

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Re: 1524: "Dimensions"

Postby mattcoz » Wed May 13, 2015 4:45 pm UTC

Envelope Generator wrote:May I ask you if you've considered all the possibilities that "down" might offer you?

What is "down" in terms of dimensions?

This brings up an interesting question though. If everything was moving inexorably forward through another dimension and allowed to move freely through time, what would be different? I would think the math would end up being the same, but is there more to it than that?

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Re: 1524: "Dimensions"

Postby cellocgw » Wed May 13, 2015 4:49 pm UTC

da Doctah wrote:
niauropsaka wrote:Do other dimensions even have names?

    Marilyn McCoo
    Billy Davis, Jr.
    Florence LaRue
    Lamonte McLemore
    Ron Townson


That's worth an internet or two! Then of course, can someone name the last temptation (not of christ)? :twisted:
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Re: 1524: "Dimensions"

Postby cellocgw » Wed May 13, 2015 4:51 pm UTC

wayne wrote:
rmsgrey wrote:
CharlieP wrote:(Veering off-topic)

Several years ago I tried "inventing" a variant on noughts-and-crosses, played in four dimensions. From (hazy) memory it had a 3x3 grid of the usual 3x3 grid, so "lines" could be completed horizontally, vertically or diagonally on a single grid, by using the same cell position in grids in a horizontal, vertical or diagonal line, or (I think) a combination of both. So if putting a cross in the centre cell of the grids in the top row could be considered analogous to completing a "vertical" line, it follows that putting a cross in the centre cell of the grids in the left column would be a fourth dimension.

I tried running it past a friend.

"But the fourth dimension is time!"

"No, in this particular game there are four dimensions, drawn in 2D".

"But the fourth dimension is time!"

"Popularly, yes. But in the context of this game I'm using four directional dimensions, to make it more interesting".

"But the fourth dimension is time!"

I gave up on the concept.


I got bored with it once I showed it was a trivial first player win and moved on to 4x4x4 instead.


I did the same thing in high school, 20+ years ago. I tried a 5x5x5, but it wasn't as much fun.
But then, I don't care for the larger Rubik's cubes, either. Once you know the concept, just sitting there twisting a cube around gets old, fast.
Some games actually get easier when you go big. They give more room to compensate for errors.

Maybe a 5x5x5x5 game would be more interesting. It might be that tic-tac-toe needs to be a grid of (D + 1) ^ (D - 1) Where D = dimensions used for play.
If you could invent such a thing, make sure you copyright it! Every textbook writer will want to use it for educational purposes. (I'd invent it, but I'm too damned lazy.)


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Re: 1524: "Dimensions"

Postby orthogon » Wed May 13, 2015 5:05 pm UTC

azule wrote:I also had a small feeling a familiarity with this comic's concept, but to find out that it's exact-FUCKING-ly the same???!!!


I agree with the thesis, but must take issue with your tmesis.

mattcoz wrote:If everything was moving inexorably forward through another dimension and allowed to move freely through time, what would be different? I would think the math would end up being the same, but is there more to it than that?


Time is different to the other dimensions: it's timelike, whereas the others are spacelike. What I'm not clear about is whether the inexorable movement therethrough is a fundamental result of its being timelike. My colleague is fond of saying that we are all travelling through time at the speed of light, unless we start moving through space, which is equivalent to pointing our velocity vector, which is still of length c, in a (slightly) different direction with respect to the four axes. However, it's not that simple: because of the nature of time (that tricksy i factor), pointing the vector into space makes us move more rapidly through time as well (all speeds are with respect to our "proper time"). What if there were more than one timelike dimensions? Would we be able to steer between the timelike dimensions, keeping a constant speed and staying in one place with respect to the spacelike dimensions?
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1524: "Dimensions"

Postby Gwydion » Wed May 13, 2015 5:32 pm UTC

mattcoz wrote:
Envelope Generator wrote:May I ask you if you've considered all the possibilities that "down" might offer you?

What is "down" in terms of dimensions?

Toward the enemy's gate, of course.

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Re: 1524: "Dimensions"

Postby Quizatzhaderac » Wed May 13, 2015 5:39 pm UTC

cellocgw wrote: Then of course, can someone name the last temptation (not of christ)? :twisted:
Trick question!
The last Temptation so far is Bruce Williamson, the 27th Temptation. However the set of all "Temptations" is not bounded, so the question of which is last in the absolute sense can't be answered.
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Re: 1524: "Dimensions"

Postby Pfhorrest » Wed May 13, 2015 7:13 pm UTC

Z dimension, or forward-backward: the dimension of your motion vector
Y dimension, or up-down: the dimension your motion vector is curving in
X dimension, or left-right: the dimension perpendicular to the plane of the other two
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Re: 1524: "Dimensions"

Postby orthogon » Wed May 13, 2015 7:15 pm UTC

Gwydion wrote:
mattcoz wrote:
Envelope Generator wrote:May I ask you if you've considered all the possibilities that "down" might offer you?

What is "down" in terms of dimensions?

Toward the enemy's gate, of course.

No, it's toward your panther's partner's genitals. (Predictive text made that particularly surreal and disturbing)
xtifr wrote:... and orthogon merely sounds undecided.

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Re: 1524: "Dimensions"

Postby cellocgw » Wed May 13, 2015 7:39 pm UTC

Pfhorrest wrote:Z dimension, or forward-backward: the dimension of your motion vector
Y dimension, or up-down: the dimension your motion vector is curving in
X dimension, or left-right: the dimension perpendicular to the plane of the other two


True for optics; false for aircraft (where X is the direction of motion, strangely enough. Guess they wanted Z to be parallel to gravity)
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Re: 1524: "Dimensions"

Postby mikrit » Wed May 13, 2015 8:17 pm UTC

Aren't there plenty more dimensions in dimensional analysis, like luminosity per mass-length and whatnot? But maybe they only have the name (that is: the family name, Dimension) in common with the four that became famous.

I tried to understand why dimensional analysis works, once. Didn't succeed, though.

PS: remarkable memory you got there, ggh.
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Re: 1524: "Dimensions"

Postby Heimhenge » Wed May 13, 2015 10:00 pm UTC

mikrit wrote:Aren't there plenty more dimensions in dimensional analysis, like luminosity per mass-length and whatnot? But maybe they only have the name (that is: the family name, Dimension) in common with the four that became famous.

I tried to understand why dimensional analysis works, once. Didn't succeed, though.

PS: remarkable memory you got there, ggh.


The first time I ran into dimensional analysis I was amazed that worked as well as it did. Of course, you need to be sure you have included all the possibly relevant parameters. That can sometimes be tricky. If you're looking to derive the formula for how long it takes water to empty from a container with a hole in the bottom (my first attempt) that's pretty easy to do. But I'm not sure it would be of much value for a truly non-trivial question. And either way, then you've got to run an actual experiment to measure the proportionality constant.

[EDIT: Just realized I never answered the question.] I'm pretty sure dimensional analysis works because it's based on the definitions built into SI, and that's a rigorously crafted and internally consistent system.


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