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## Math for fun and glory

# A song about a circle constant

Happy Tau Day! This is a song about Tau! Other Tau things you should see:Pi is (still) Wrong: http://youtu.be/jG7vhMMXagQ What Tau Sounds Like: http://youtu.be/3174T-3-59QThe Tau Manifesto: http://tauday.com/. Created by Vi Hart.

## Want to join the conversation?

- Did anyone else notice that when Vi was singing the digits of tau, the higher the digit of tau, the higher the note she sang was? (except 0 which was the highest)(466 votes)
- That was the point. The notes correspond to the value of the digit. Kinda cool to hear how the numbers translate into music.(328 votes)

- 6.

2831853071 7958647692 5286766559 0057683943 3879875021

1641949889 1846156328 1257241799 7256069650 6842341359

6429617302 6564613294 1876892191 0116446345 0718816256

9622349005 6820540387 7042211119 2892458979 0986076392

8857621951 3318668922 5695129646 7573566330 5424038182

9129713384 6920697220 9086532964 2678721452 0498282547

4491740132 1263117634 9763041841 9256585081 8343072873

5785180720 0226610610 9764093304 2768293903 8830232188

6611454073 1519183906 1843722347 6386522358 6210237096

1489247599 2549913470 3771505449 7824558763 6602389825

9667346724 8813132861 7204278989 2790449474 3814043597

2188740554 1078434352 5863535047 6934963693 5338810264

0011362542 9052712165 5571542685 5155792183 4727435744

2936881802 4499068602 9309917074 2101584559 3785178470

8403991222 4258043921 7280688363 1962725954 9542619921

0374144226 9999999674 5956099902 1194634656 3219263719

0048918910 6938166052 8504461650 6689370070 5238623763

4202000627 5677505773 1750664167 6284123435 5338294607

1965069808 5751093746 2319125727 7647075751 8750391556

3715561064 3424536132 2600385575 3222391818 4328403978

7619051440 2130971726 5577318723 0676365593 6460603904

0706037059 3799154724 5198827782 4994435505 6695826303

1149714484 9083013919 0165906623 3723455711 7781501967

6350927492 9878638510 1208018554 0334227801 9697648025

7167232071 2741532020 9420363885 9111923978 9353567489

8896510759 5494536942 0809506929 2416093368 5181389825

8662735405 7978304209 5043241139 3204811607 6300387022

5067648600 7117528049 4992946527 8283985452 0853984559

3564709563 2720186834 4328243984 9172630060 5723659491

1141349967 7010989177 1738539913 8185442159 5018605910(15 votes)- Wow. That would have taken a while to type. Great Job!(4 votes)

- So is the circumference of a circle Tau*radius?(12 votes)
- Pi is circumference divided by diameter. That's why diameter multiplied by Pi equals circumference. Tau is circumference divided by radius.(2 votes)

- i also wonder how she got to make her own videos on KhanAcademy!(3 votes)
- Vi started her own math videos on YouTube. Her fame is quickly spreading, and of course, Sal, being a cool guy, found out about her, and probably asked her directly to feature her videos here!(3 votes)

- at1:19what is a 4 dimensional object(2 votes)
- Actually, Steven Hawking has speculated that all objects have 4-dimensions, and the fourth dimension is time. Like, as an object grows older, the volume (or whatever you'd call it) of it's fourth dimension would increase.(5 votes)

- She has a very unique voice don't you think!(3 votes)
- Yep, it sounds a lot like her speaking voice in other videos.(2 votes)

- Isn't Tau basically Pi times 2?(3 votes)
- Tau is exactly Pi times 2. That is a logical consequence of their definitions.(2 votes)

- So does this mean what I learned in elementary school is wrong and my 6th grade math teacher celebrated pi day for no reason?(T-I)(3 votes)
- No, pi is true but it isn't right, the point that Vi is trying to get to in the video. To quote, "We get further from truth when we obscure what we say".(2 votes)

- Is Vi the one playing the guitar?(3 votes)
- Yes, Vi is playing the guitar in this vid. (it's awesome right!)(2 votes)

- At0:27, why did she start singing about tau? Tau is just

3.141592653589793... x 2

= 6.28318530717958647692528676655900576839433875021.....

Tau is just pi + pi or pi times 2.

(I got the whole thing from Vi)

And the notes... they are higher the higher the digit is. 0 is the highest.

WHY?(3 votes)- Because zero is at the end of the keyboard. It's like this from lowest to highest: 1 2 3 4 5 6 7 8 9 0(1 vote)

## Video transcript

(SINGING) When you want to
make a circle, how is it done? Well, you probably will
start with the radius 1. Then use a compass or a string,
and use a paper or the ground. And if the radius is 1,
how far did you go around? It's tau, 6.28. Yeah, it's tau,
6.28318530717958. If you pick a certain distance,
and you pick a certain spot, and you put the two together,
then what have you got? It makes a very special shape,
and now you are the inventor, if you take all of the
points a certain distance from your center. And you've got a
great collection, and it is a great invention. And it makes a lovely circle,
well, depending on dimension. Because it's 1, 2, 3, then
there's 4 and even more. But for a circle,
how much circle's there if you take the
distance and compare? It's tau, 6.28. Yeah, it's tau,
6.28318530717958647692528. I know what you are thinking,
what about that other guy? The one that's
sometimes pronounced pee, and it's sometimes
pronounced pi? I mean, it's fine if you
are building, but does not belong in math. All the equations make
more sense when you use taw or you use taff. Well, you get the same
answers no matter which way. We get further from truth
when we obscure what we say. You know that math makes sense
when it's beautiful and pure. So please don't make it
ugly with your bad notation and awful curriculum. Use tau, 6.28. Yeah, use tau,
6.28318530717958647692528676655900576839338750211.