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Does this tattoo equation mean to you what I mean it to?
May 15, 2011 8:26 PM   Subscribe

Math and science geeks, does this fake equation make sense? 'delta' = c ... meaning "change is constant".

This is for a potential tattoo. I figure though it's not necessarily completely mathematically or scientifically accurate, it gets the point across - do you, as a math and/or science geek, agree? I.e., would you get it without an explanation? Is there a better way to express it?

Bonus follow-up for the lightning round: is there a good way to represent, "The only constant is change"?
posted by attercoppe to Grab Bag (33 answers total) 2 users marked this as a favorite
d state
--------- != 0
d time

(I can't really represent that right in just text characters, but it's supposed to be differential calculus.)
posted by Chocolate Pickle at 8:29 PM on May 15, 2011

"Math and science geeks, does this fake equation make sense?"

No. I wouldn't get it, and I would think it was a dumb tattoo after it was explained to me.
posted by Jacqueline at 8:29 PM on May 15, 2011 [1 favorite]

I'm just one mathematician, but I would roll my eyes if I saw this tattoo. Also, I think it would not get your point across without a belabored explanation on your part.
posted by escabeche at 8:30 PM on May 15, 2011 [4 favorites]

You might be able to get away with ∆ ≠ 0 — "change is never zero". But to me (another science/math type), this is not unlike tattooing a Chinese word on your body without knowing a word of Chinese.
posted by Johnny Assay at 8:33 PM on May 15, 2011 [5 favorites]

It sounds like you're getting a tattoo in a language foreign to you. Always a bad idea.
posted by supercres at 8:34 PM on May 15, 2011 [20 favorites]

It seems a little forced to me. No. Get the quote in Latin or Elvish or something if you want to amp up the dorkage. Or quote Spinal Tap ("The more that it stays the same the less it changes").

I'd only do the equation tattoo if the resulting quote was something particularly amusing or puzzling it out was particulary fun. Otherwise, no.
posted by It's Never Lurgi at 8:34 PM on May 15, 2011

Yeah, c is the speed of light, not just any old constant. Belabored is exactly the word for the meaning behind your equation.

Maybe ∆life/∆t ≉ 0? That's pretty cheesy.
posted by cmoj at 8:35 PM on May 15, 2011 [3 favorites]

Gotta say that I don't see that statement working in a formula. If anything, I was thinking it might work in Latin, but it is pretty close since change and constant have their roots in Latin already.

I would talk to a good tattoo artist and see if they can come up with a graphical representation.
posted by slavlin at 8:37 PM on May 15, 2011

Is there a better way to express it?

Bonus follow-up for the lightning round: is there a good way to represent, "The only constant is change"?

If you want to express that concept, you could use those exact words, and anyone who spoke English would understand them.
posted by pompomtom at 8:51 PM on May 15, 2011 [4 favorites]

Isn't it ironic to write that out indelibly on yourself? "The only constant is change, and this tattoo."
posted by fzx101 at 8:53 PM on May 15, 2011 [15 favorites]

I'm not a mathematician, but a constant value in a formula has a single quantity assigned to it, so c can be 0, or 12, or 15. In other words, you're saying that delta isn't changing. I also think that delta ≉ 0 would make more sense, as that implies that delta isn't always the same which kind of seems to be what you're going for.
posted by tomtheblackbear at 8:58 PM on May 15, 2011

Yeah, c is the speed of light, not just any old constant.

c is frequently used for any old constant.

If you want to go with a mathy tattoo, you could just tattoo the delta, which I think is a fairly pretty letter.
posted by hattifattener at 9:01 PM on May 15, 2011 [3 favorites]

In math, change in the independent variable over time is represented by dx/dt or just x with a dot over it (x dot).

So you can use x dot = k where k is a constant, but it doesn't get across what you're trying to say, I don't think. It's just makes a boring linear equation: x = kt.

I think what you want to get across is the concept of chaotic change, not smooth differentiable change, and I think it might be more interesting to get one of the many chaotic formulas tattood, like the Mandelbrot formula:
posted by empath at 9:17 PM on May 15, 2011 [1 favorite]

The letter c, as a physicist, could mean several things. Wiki.

In math, it's the "plus c" found when finding an integral.

What that has to do with delta, which is either a change in a variable or the Laplace operator, I wouldn't know.

I'd assume, like many people above, that you've gotten a tattoo in a language you don't understand to try to convey something that could simply be written in English.
posted by Brian Puccio at 9:36 PM on May 15, 2011

Also, '=' means identity, and I've never taken the 'is' in that expression to be identity. Maybe predicate logic would get you closer, but I'd echo the mathematicians above.
posted by chndrcks at 9:56 PM on May 15, 2011

How about getting panta rei tattooed? It expresses the same idea, is in an unusual language, and seems like it would be much more likely to elicit knowing smiles than exasperated sighs.

Just a thought.
posted by artichoke_enthusiast at 10:09 PM on May 15, 2011 [1 favorite]

How about "plus ca change, plus c'est la meme chose?"
posted by Gilbert at 10:09 PM on May 15, 2011 [1 favorite]

You could also quote one of the presocratic philosophers who expressed a similar thought:

πάντα χωρεῖ καὶ οὐδὲν μένει” καὶ "δὶς ἐς τὸν αὐτὸν ποταμὸν οὐκ ἂν ἐμβαίης"

Everything changes and nothing remains still .... and ... you cannot step twice into the same stream
posted by empath at 10:43 PM on May 15, 2011

Even if I guessed at what you trying to do, ∆=c just says the rate of change (over what time interval?) is constant. δ is overloaded enough as a variable that it'd be very hard to guess you what actually meant (and math people would probably be thinking of real analysis, where δ=0 could imply the function is constant).

The real problem here is that there's no symbol for 'the process of change', which is what you really are talking about, and even if there was, assigning a constant to it would mean 'the process of change is always the same one.' Seconding just using ∆ - as long as it definitely looks like a delta and not a triangle (the right side can be made thicker, this makes it pretty recognizable).

Alternately, maybe the first couple loops of some chaotic function would get the point across ("rarely in the same place twice")? And if you wanted to have to explain it to people, I'd get some attractor like this one that looked pretty cool.
posted by devilsbrigade at 10:49 PM on May 15, 2011 [1 favorite]

c = speed of light. C is the constant you're looking for. But delta isn't used by itself, it's the change in something, so even if you used the upper-case C your equation would mean "the delta symbol = the constand of integration" which is meaningless. I think the best you can do, riffing on Johnny Assay, is "∆x != 0," which means "the change in quantity x is not zero." Still pretty weak though.
posted by zanni at 10:54 PM on May 15, 2011

May I suggest something to do with exergy and entropy instead? Equations (1) [the dB/dt part] and (2) from that link are a very physical interpretation of non-zero change. Of course, "change is constant" in the context of entropy is a grim reminder of the inevitable heat death of the universe. But that's what makes it funny.

But then, that's also pretty obscure. Maybe physicists would get it, but I wouldn't recognize it except for the fact that I've just been reading Wikipedia.

For best results, typeset in LaTeX, print that out, and give that to the tattoo artist. This will give you the same font used in mathematics publications.
posted by qxntpqbbbqxl at 11:19 PM on May 15, 2011

I rather agree with "sounds like you're getting a tattoo in a language foreign to you." The proposed equation is not very meaningful as presented (I'd probably initially parse c as either the speed of light or, perhaps, as concentration), and you'll have to go through an awkward explanation any time anyone with any science/math knowledge asks what it means. I'd probably cringe a little at the explanation, as a scientist, since it really feels like quite a stretch, but it is of course your prerogative to not care about my cringing.

If you're looking for a text-based alternative that gets a similar sentiment across, you might be able to do something with one of a variety of well-known quotes about change, e.g.:
"Omnia mutantur, nihil interit" (all things change; nothing perishes)
"Omnia mutantur nos et mutamur in illis" (all things change, and we change with them.)
Or even simply "Omnia mutantur" (all things change)
These quotes are, of course, Latin, and thus still a foreign language, but they actually mean something in that language.
posted by ubersturm at 11:34 PM on May 15, 2011 [1 favorite]

Heraclitus who coined panta rhei also has this quote: Ever-newer waters flow on those who step into the same rivers., and I like this because there's a Japanese text, Hōjōki, that starts Ceaselessly the river flows, and yet the water is never the same, while in the still pools the shifting foam gathers and is gone, never staying for a moment...

Both capture the idea of constant change, but might be a bit long for a tattoo. I guess panta rhei (Πάντα ῥεῖ) might work better. And Wikipedia says there's a Japanese "expression of mujō, the transience of this world", however mujō just redirects to Impermanence with no further info. Might be work looking into though.
posted by bjrn at 11:45 PM on May 15, 2011 [2 favorites]

I agree with many above that 'delta' = c would look weird, it rather describe something constant than something changing.

The best indicator of random change I can come up with is the Lyapunov exponent of a system. Lambda > 0 means a chaotic system so something like |δ life| = exp(t) |δ life| would mean that life is unpredictable.
posted by furisto at 5:35 AM on May 16, 2011

Mathematicians don't often use just the Greek letter delta to signify "change", we usually want to talk about the change in a certain variable. Hence, we use things like "Delta x" or "Delta y" depending on what we're talking about.

I would not get this tattoo. I, too, would roll my eyes after you explained it to me.
posted by King Bee at 7:12 AM on May 16, 2011 [1 favorite]

Perhaps one of the equations from this page. dS/dt ≥0 is familiar to physicists and engineers. There are different interpretations; d\vector(p)/dt ≠ 0 (newton's second law for a system not at rest in any inertial reference frame) might get your meaning better. There is no standard notation for the set of inertial reference frames that I recall, but I don't have my relativity text handy.

In any event, be prepared for awkward conversations with someone who understands physics.
posted by a robot made out of meat at 7:22 AM on May 16, 2011

May I suggest something to do with exergy and entropy instead?

I know someone with an 'Entropy Always Wins' tattoo that gets the same idea across.
posted by youarenothere at 7:58 AM on May 16, 2011

I know someone who has a tattoo that says "∫∆♥dt≠0" which roughly translates to the change of love over time is never constant, or at least that is how the person explains it to laymen. I can't give much input about the geek perception of it because I think it's just a riff of of this XKCD comic.

Seconding the mathematic typeset in LaTeX because that aesthetic is easily recognizable and iconic for those who have had to stare at equations for a long time.
posted by joydivasian at 8:18 AM on May 16, 2011

The only (short) equation that captures what you want to say is a robot made out of meat's answer: the second law of thermodynamics. Beware that it's often intrepreted as a negative statement though (it's number 2 on the list below). In this sense, the laws of thermo can be cynically put as:

0. Existance is a game you must play.
1. You can't win.
2. You can't even break even (things always get worse).
3. You can't quit.

Thermodynamics is very Hobbsian.
posted by bonehead at 8:39 AM on May 16, 2011 [3 favorites]

I don't think I'd ever use "c" as my go-to for a constant. That's usually "k". "c" is generally the speed of light.
posted by chairface at 11:50 AM on May 16, 2011

I agree with bonehead -- the second law of thermodynamics would cover it. Otherwise, just get a chaos star and call it a day. You could also express "the only constant is change" with an ouroboros or a phoenix: both express the idea of an always-changing, ever-dying-and-renewing existence.
posted by vorfeed at 11:59 AM on May 16, 2011

Thanks all, some fantastic comments here. I'm going to go the "they're all so good I can't pick even a few" route. Good points on the original suggestion, good thoughts on alternatives. Answered!
posted by attercoppe at 9:56 PM on May 17, 2011

Oh, and a quick P.S. to fzx101: Yes, that's part of the point. A permanent tattoo that says everything changes.
posted by attercoppe at 9:58 PM on May 17, 2011

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