A physicist named Michael Hartl wants us all to scrap pi and instead use a mathematical constant he calls tau, which is equal to two times pi. (It’s the circumference of a circle divided by the radius instead of the diameter.)
Tau makes a lot of formulas neater. For example, when you’re describing counterclockwise rotations on a unit circle, does anybody really understand why 180 degrees should be equal to pi? But a full 360-degree revolution equal to tau — that makes sense.
Anyway, we’re semi-convinced, so we’re adding Tau Day to the MuseBlog calendar on June 28. Now somebody has to invent something tasty called a “tau” for us to eat then.
Hm. It seems like it could be a good idea, but there are a lot of applications to consider. It would make the unit circle a tad more logical. Hm… *goes off to research*
There’s a site which is the first result for “Tau Day” that gives a quite thorough set of arguments for Ï„. I’ll call myself convinced, though I find it doubtful that it will be adopted by the mathematical and scientific communities.
First comment?
AAHHHH!!! HOW DARE YOU TAKE AWAY PI???? CAKE YOU, MICHAEL HARTL!!!! OHHH, YOU WILL BE SORRY! AND I WILL NEVER, EVER, EVER MEMORIZE ANY DIGITS OF TAU! IN FACT, I WILL DISTINCTLY FORGET ABOUT IT!!
3.141592653589793238462643383279502884197169399375105820974944592307816406286208998628034825342117067!!
THAT IS 100 DIGITS!!!
There will still be pi. Don’t worry.
It’s just it will be less important, and make life easier.
I am still mad at Michal-I mean-He-Who-Should-Not-Be-Named, though.
Nooooooooooooooooooooo. Things would be way more efficient if quite a few other things changed, too, but we’re not converting, are we?
Grrrrrr.
Curses.
The difficulty with something like this is that there are going to be people who are more used to using pi, and so if we start teaching tau in schools, mathematical communications between older and younger people will get very confusing.
Kokopelli would approve.
On the other hand, the conversion between pi and tau isn’t very difficult.
Ï„=2Ï€
Ï€=0.5Ï„
It’s certainly simpler than metric to “customary” or vice versa.
I hate customary to metric conversions.
They have a symbol for tau already??
Tau is a Greek letter, just like pi. They’ve had a symbol for it for a couple thousand years.
Ohhhh…*feels clueless*
They’re pretty confusing as is. Mom keeps laughing at me for not knowing how to use a slide rule. I keep laughing at her for not knowing how to do advanced algebra.
I’m all for this, or at least, all for giving this a shot. It seems to make things simpler, and after all, isn’t that kind of the point of mathematics? To make order out of chaos?
I really don’t feel like changing my username to vanillabeantau. Anyway, pi can’t every completely go away, at least not in trig, right? It’s the period for tangent, cotangent, secant, and cosecant. I don’t see what the big deal is anyway.
It’d make what we’re doing in math class right now easier.
How is tau pronounced? Does the au sounds like ow?
8- Yes. Tau rhymes with cow.
Muse should have a short article on this. I’m sure Urania would have some opinions on the matter.
Article request seconded. It would have been perfect for this past issue, actually.
Thirded. I’d like to hear more about it.
Fourthed!
sounds like an exciting thing to try out. If it doesn’t work, people will stop using it, whereas if it catches on, Pi may fade from our mathematical formulas.
Not from mine!
So what would the equasions for area and circumference look like? †r for circumference and… †/2r^2 for area? The circumference is certainly simpler and neater, but I’m not sure about the other one. It’s somewhat more complicated, and I’m not sure it’s correct.
I really don’t particularly care either way, myself. Apart from a lingering affection for Pi as the concept I’ve always known, I can’t see any real difference. Especially since the above equations are pretty much the sum total of my knowledge of the Uses of Pi. Math isn’t really my favorite subject.
I don’t care, I’m just worried about pre-calc next year…. My math teacher says it’s harder than calc. Joy. 2 hours of math homework here I come.
I don’t know if it’s just my particular class, but pre-cal is really easy. It’s pretty much a repeat of Algebra 2/Trig.
I don’t think a circle as 2pi radians is that difficult, and I just learned about tau as the symbol for torque in physics, which would be annoying because then your tau (torque) could be equal to 2tau newton*meters or something.
12-Adeia- I was in pre-calc last year. It wasn’t too bad, but there is a lot of information to remember and a lot of difficult algebra. Calc is slightly easier because the pre-calc stuff has become easy through practice and constant application.
So I memorized 52 digits of pi for nothing???? I don’t want to have to double and do all that math every time I want to recite pi. Besides, the switch would be more trouble than is worth just popping a X2 into your calculator.
Is there a thread for pi memorization? Because I’ve got 100 digits, and I am NOT memorizing tau.
I will not switch. Even if pi doesn’t disappear, I know its applications. I am not going to the trouble of learning a new number that doesn’t even rhyme with a comestible when a simple multiplication by two would do the job! We count in base ten, don’t we? Ten is an even number, isn’t it?? According to Muse itself, multiplying by two is simple!
Chow. Cacao.
Summer Glau? She’s not a foodstuff, but some xkcd characters consider her delectable.
I’m still waiting for somebody to suggest something good to eat that we can call a “tau.” Some sort of double-decker pie, perhaps?
Hm. Black-bottom pie has two main layers: a layer of chocolate pudding and a layer of custard. It would be an excellent tau. We know that Jadestone makes it. I wonder whether hers is as good as mine.
(Honestly, though, I don’t think pi has anything to fear from tau. Pi is too entrenched, as the outraged response from normally forward-looking MuseBloggers indicates.)
I’m not sure MuseBloggers are always all that forward thinking when it comes to these things. Remember the uproar over Pluto?
I’m thinking a pie with a filling that’s like pudding but more cakey.
OM NOM NOM
And I have no doubt that your black-bottom pie is delectable! I only helped a friend make it (doubt I could make one on my own), but it was certainly delicious.
I do like the idea of a two-layer pie though. But perhaps one sort of filling, a thin layer of crumbly crust, and then more filling on top? It would have to be a rather deep-dished pie.
This sounds like a good project for a 2-am baking party. I’ll think about it. XD
Oh dear. Oh d-d-d-dear. I just realized something: with the slightest provocation, this whole matter could easily explode into a civil war on Norris/Watership or even Cat v. Dog proportions.
TEAM TAU FOREVER
I’M WITH YA
ONWARD! TO PI WAR!
PI WILL CONQUER!!!!
WE HAVE TWICE YOUR POWER, YOU WILL NEVER AVAIL!
WE HAVE SO MUCH POWER WE CAN FORGET THE DIFFERENCE BETWEEN AVAIL AND PREVAIL AND STILL PREVAIL
THE OLD EQUATIONS ARE MORE POWERFUL!
(In post 17.1.1.1.1 you should have used a semicolon instead of a comma.)
THE ALLIANCE OF TAU WILL PREVAIL
TEAM PI!!!
Oh dear. Is this going to turn into that cat-dog wars again? will the HPBs have to interfere?
Team Pi!!!!!!!!
PI! PI! PI! *starts to chant*
REASONS FOR PI:
-What about Pilish? WHAT ABOUT PILISH? Has anyone invented Tauish? I didn’t think so.
Can I give a price, Agent Lightning, on lemony peace for their piefully PItacular KOKOPIE????!!!!!!!
(Yes, that was in Pilish.)
-Pi is yummy. And I do indeed mean the mathematical concept.
-Since when have we without question gone with what makes a lot of things EASIER/SIMPLER? It would be better to all convert to dozenal (and I’ll give you a ton of reasons) than the metric system, but…hmm. It seems we aren’t doing that. Tau makes a few things the tiniest bit easier, and we immediately switch to it???!!!!!! What right does tau have?!
What right does pi have?
It was there first. (Shh! It makes sense!)
Tau, being a mathematical concept, has no right. Neither does Pi. As for switching to a dozenal number system, that would take much more getting used to than doubling Pi, and in fact mathematicians are all over simplification, and I’m sure would love to switch to a 12-based (or even 60-based) system if the general public would allow it.
If Pi is yummy, shouldn’t Tau be twice as yummy?
No.
Exactly. Why do you think Rube Goldbergs are so popular?
Until they come up with a dessert that is a homophone of ‘tau’, I’m staying neutral.
I say that we should stick with using Pi!
What do we throw at eachother for comedic effect? Pies!
What have we been using for the longest time? Pi!
Besides my two perfectly valid reasons, my favorite aquatic creatures are Octopi (badum tish).
Our minotaurs will smash your octopuses to bits!
Just for that, your side gets brownie points from me.
*Is teuthophobic*
Octopi have more limbs than minotaurs!!
Minotaurs have more horns than octopuses.
But octopodes are smaller, allowing them to (slither? squirm? wiggle?squelch?) out of the way as the bigger, gallumping minotaurs charge and fall off of a cliff.
But minotaurs have more wings than octopi/octopuses/octopodes!
…
Wait, no they don’t.
Octopi live in the sea, and therefore when the minotaur tries to attack it, it drowns.
SFTDP-But I forgot the most important point, the ace in the hole
Minotaurs don’t exist-And neither should tau
MWAHAHAHAHA!!!
Ah, Kai. You and your fear of cephalopods. By the way, I’ve been meaning to ask you about that. You’re the only one I know with that fear, so I’m curious. Do some cephalopods scare you more than others? And is size a factor? For instance, are you afraid of giant squids, but not, say, flamboyant cuttlefish? (They are only two inches long.)
Also, is this a PoPo? If it is, I am sorry and will gladly pay the fine.
I’m okay with cuttlefish, as I actually like their shells. I’d say the size that causes me to freak out is anything with a body as big as my head or larger.
I guess I’m lucky that I’m afraid of something I realistically won’t run into very frequently. There’s just the occasional museum or aquarium exhibit to walk past very quickly with averted eyes while jauntily humming. And then, of course, the discussions of Lovecraft to politely excuse myself from.
Google-searching has told me that fear of cephalopods is somewhat common, although there isn’t a recognized name for it. However, from the Greek roots and the fact that “teuthology” is the study of cephalopods, “teuthophobia” would be the appropriate term.
I have a friend who is afraid of whales.
I would like to point out at this point that the correct plural form of ‘octopus’ is ‘octopodes’.
Not necessarily. “Octopi” and “octopuses” are also considered correct.
Yeah, because when a word is adopted to another language, (in this case, English) it mutates, but that doesn’t make it any less correct.
“Octopi” shouldn’t be correct, though, because the “us ” ending doesn’t come from Latin. It’s similar to platypus.
(I have heard etymologically minded marine biologists say “octopods.”)
I support pi. It’s traditional.
YAY TRADITION!
Taufee. Taupioca. Taurte. Tauramisu.
TAU SHALL TRUMPH
PI IS PIFFLE
Reasons for pi
1. Pies, pi-It’s so fun to associate
2. The symbol looks cooler
3. It’s already engrained in the heads of people who have memorized digits-I have 52 down, trying to memorize more and will never memorize Tau
4. Without pi, where would this little trick to remember equations be?
Cherry pie is delicious
C=Ï€d get it?
Apple pies are too!
A=Ï€R^2 Now try doing THAT with Tau
5. Everyone would need new graphing calculators, new programs, and a bunch of new stuff just for Tau. I don’t think so.
How do you do pie emoticons?
Regarding number 4– I find those confusing. I just memorize! So a tau formula would be just as easy as a pi formula. Yay.
Actually… just thought of one… Cower.
C=Ï„r, get it?
Now all that remains is the area one!
Piggy and SudoRandom: the Two Tau-ers.
Except I supported Tau before Sudo, in post 2.1…
Incidentally, “pi” isn’t actually pronounced like “pie”. That pronunciation was created by mathematicians who are horribly ignorant of basic linguistics. Pi is actually pronounced “pee”. Tau, on the other hand, is pronounced to rhyme with “cow” both linguistically and mathematically.
Anyway, enjoy your pee. Er, pi.
Pronunciation doesn’t matter much with Pi. At the end of the day, we can all enjoy a nice Pi, right?
Besides, telling people the proper way to say Pi is pretty much telling them, “Go ahead, make lame puns like a fifth grader!”
Ahem.
Ghost of Tau girl? Pfft.
GO PI!!!!!!
How do you do pi emoticons??
I don’t know about pi, but pie is colon, exclamation point, then colon again
A flying pie is colon, arrow (the word) then colon again. Like this, except without the spaces in between the colons and the thing in the middle
: ! :
: arrow :
: arrow :
I think Tau would make things a lot easier.
TEAM TAU WILL WIN! WE HAVE ALLITERATION, WHILE TEAM PI DOES NOT!
Pi Party? Pi Partners? Pi Pack? Pi Posse?
I think I’ll join the “Both Bunch” with Cat’s Eye.
…I think both pi and tau are very nice.
Channeling Mimi, eh?
There can be no compromise! Pi must win completely and totally over tau. Pi will dominate!
Hey, all we want for Tau is acceptance. We’re not aggressive except for when it comes to Equal Rights. Does anybody have a problem with that?
Yes, they’re both very nice, and equally so, but Tau is better.
Agent Lightning- : ! : without the spaces is
, : arrow : without the spaces is 
. How to do all of the smileys is at the top, under H*G*T*M*B- Smileys and Code Tricks.
If tau = 2pi, then why is the symbol only half? Ehhhh? *raises eyebrow*
It’s another advantage! It saces the ink of mathematicians
τ τ τ τ
DONT FORGET YOUR TAUWEL
Also, π = π, and τ = τ.
Huh. I could have sworn Tau already meant something in math (something other than 2π).
Maybe in Science.
According to wikipedia, it’s occasionally used for phi/the golden ratio.
A-ha! I knew I’d heard of it before!
Okay, so. Pi = 3.141…
Tau = 6.282…
Pi: C= π d
A= π r^2
Tau: C= τ r
A= τ …and what? r/2^2? r^2/2? That certainly isn’t simpler.
An explanation of Pi I found explains that Pi is equal to 3.1415… times the diameter, which is correct. And tau is equal to 6.28210 (I think)… times the radius.
Why can’t we use both? If tau makes an equation easier, then why can’t we use it for that equation, and if Pi is simpler (such as when trying to find the area of a circle, it would seem) then we can use that. It’s hardly difficult to memorize both; the first two or three digits are the commonly used ones and those can both be doubled easily, with little effort.
Perhaps if we found had found tau first, Pi would make more sense (explaining the whole 180 degrees thing, for starters.). Or not.
However, Pi is still much awesomer than tau, for the simple reason that it will always be linked to the flamablamablous food pie.
TEAM PI
A= τ/2 * r^2
It’s fairly simple.
Actually, cancel that. The explanation Hartl gives is:
1/2 * τ * r^2
Just like the equation for kinetic energy is:
1/2 * m * v^2
Or the equation for distance fallen (in a vacuum) is:
1/2 * g * t^2
But A= π r^2 is the same thing, without the diving by two. Which is simpler.
So why can’t we use both in mathematics?
Because it would be redundant.
Oh, and re: food?
We have taules. (towels)
You Are Never Safe Without A Taule?
Isn’t taule a word in Sindarin or Quenya or something?
We don’t have to spell pie differently. Ha.
Um. I’m a delegate of the Both Bunch (great name, Meow!) and have no opinion on either pi or tau, but I’m pretty sure that pi is spelled differently from pie, just as tau is spelled differently from tow. There’s an extra E.
I meant that pi already fits into a word without having to respell the word, whereas tau only goes into towel when you respell towel.
The author of that page… He’s quite a [
]. He’s got a lot of great points, and his math is sound, and his concept is totally waterproof… He’s just not winning himself any friends, at all. If he really wants Ï„ to catch on, it would become him to rewrite that entire ‘manifesto’.
-A
We can use it as a bad example in the manifesto-writing unit of Muse Academy’s World Domination course.
Tau makes sense, which is exactly why I don’t like it. I prefer the randomness of pi, and it’s irrationality. Promote entropy! Tau probably isn’t fun to memorize anyway. And I will never kill pi-guy never! (pi-guy is a character I invented composed completely out of pi symbols)
Well, in all fairness, tau is irrational too. (Although admittedly, I don’t feel like forgetting the 150 digits of pi I’ve memorized.)
I don’t see the need to take sides. Pi and tau are equally valid mathematical constants, right? Can’t we just use pi where it makes more sense and tau where it makes more sense?
I agree with Ambystoma. Pi and tau are equally good, each converts to the other with very little trouble. In some cases tau would make more sense, in some cases pi makes more sense. And they’re both equally irrational
But making sense is what I’m trying to prevent!
Sense or cents? Cents are round, and to make things round you can use either tau or pi. So you’re stuck with them, I’m afraid.
Actually, making cents off of not making sense is a good idea…
Cakeness. To be honest, I see the merit of using both Pi and Tau (use the one that makes more sense), but that would require a total overhaul of math classes. New memorization of digits, new memorization of formulas, new graphing calculators, the list goes on. I suppose I’m not too opposed to tau as a number, but I WILL NOT give up pi!!! By the way, we’d have to revamp our entire Muse Glossary.
PI SHALL REIGN IMMORTAL!!!!
I have done a little more research, and have discovered that τ also represents something in statistics, as well as in several other mathematics-heavy applications. So while I can definitely see τ catching on in middle and high school math classes, I can’t see it replacing π in college or in the workplace.
I just realized that the symbols/letters are backwards. Tau is 2pi, yet it is pi minus a table leg! In other words, 1/2 of the pi symbol.
Wrong!
If you think of the line on top as the line a fraction has (as in 1/2), then pi is half of tau!
1/II vs. 1/I
Oh… well I guess that makes sense. Huh, I never thought of it that way.
Using that, I have composed a tau-guy out of tau symbols places end to end
So Tau Day is on the MuseBlog calendar and Pi Day isn’t. How controversial.
Pi Day was on the calendar last year, but we didn’t have the ability to make it annual then. Now we do. It’s back, permanently.
Awesome!