"Pi is wrong" - the Tau Manifesto

[some1rational]

This may be old, but I couldn't find any posts about it (and for me, speedsolving is just as good an outlet for mathematics haha).

Read:

http://tauday.com/

or for pdf version:

http://tauday.com/tau-manifesto.pdf

I have to say, as a physics and mathematics major, I've always had an inkling that something felt 'wrong' about the usage of Pi, but it wasn't until I read this article that I could pinpoint exactly what was the problem (credit goes entirely to the author, Michael Hartl).

[for the record, I wholeheartedly agree with the author, that the usage of Pi is a "pedagogical disastor", and not that Pi the number is in some way wrong...obviously, but just in case]

So for those of you who enjoy mathematics, I'm just curious, what are your thoughts/opinions?



EDIT: The author, Michael Hartl, is a Harvard Physics PhD graduate and was a professor of theoretical/computational physics at Caltech. Just to give the article some more weight (though it doens't really need it imho).

 

[y3k9]

That's an interesting read. And btw there's a awesome math forum on aops.

 

[BigSams]

That's an interesting read. And btw there's a awesome math forum on aops.

Are you honestly saying that you read and understood this in 2 minutes?
btw I'm on aops, almost done the intermediate series

 

[y3k9]

Are you honestly saying that you read and understood this in 2 minutes?
btw I'm on aops, almost done the intermediate series

No I read a bit posted on here, and went back to reading.

 

[some1rational]

The coupe de grace was really the final straw for me. I have to commend Michael on a job well done in this manifesto. So what are your thoughts?

I for one plan to start substituting Tau for 2*Pi from now on (though it might be awhile before I will use it again lol, I just graduated and am in the midst of applying for grad school)

 

[aronpm]

**** GUYS, CALL THE MATH POLICE

SOME FORMULAS MULTIPLY PI BY 2

 

[some1rational]

@aronpm: I don't know if your being sarcastic or not, but the point is not that the factor of 2 is confusing for anyone who is even relatively acquainted with mathematics (trigonometry, complex analysis, etc.).

The point is to look at it through "the eyes of a child". A quarter turn is 1/4 of Tau, but a quarter turn is 1/2 of Pi. That, plus all the other arguments given, makes me more than convinced that Tau should be the 'natural' choice. Anyway, more discussion is always appreciated. If I can convince just one other person on this forum, I feel like I've done something lol.

 

[Keroma12]

This is very convincing, and does make many good points. It would be interesting to see somebody defend pi.

 

[cmhardw]

Wow... I'm convinced. I like the significance of Tau. The rewritten Euler's identity was what sealed it for me. Pi does feel somewhat like my S-slope after reading that.

 

[some1rational]

Yay! lol thank you for responding Chris. If this thread was a competition, convincing you is like first place prize for me haha.

 

[maggot]

i found this to be really stupid.
lets declare another variable (as if there wasnt enough already) thats completely insignificant!!!
2pi = tau.
retarded.
and it seems as though his motive is because he had a hard time grasping radian measure.
pi has its coup de grace in pi r^2... actually pi has its coup de grace because its one of the most significant numbers used in math, regardless of wether its multiplied or divided to make it look "ugly". there are a lot of ugly formula out there that need some help... PMCC's, standard deviations... just about any statistics formula lol... they're all horrible imho.

 

[einstein00]

lololololol.

In section 3, Hartl makes a big deal about the circle area formula being A = pi*r^2, when several physics formulas take the form y = 1/2*k*x^2. He then proposes that we change the formula to A = 1/2*tau*r^2. This is completely unnecessary: C = 2*pi*r, so A = 1/2*2*pi r^2 = pi*r^2. But because C = pi*D, A = 1/2*pi*D^2, which follows the general form y = 1/2*k*x^2. He's just playing with variables and numbers to fit his persuasive needs, when his argument is actually invalid.

 

[y3k9]

The quarter turn did it for me. But what I still don't understand what pi and tau are fighting for? Being called the most important constant relating to circles?

 

[some1rational]

einstein00: actually A = 1/4 * Pi * D^2, you did your calculation wrong

A = Pi * R^2 = Pi * (D/2)^2 = (Pi * D^2)/4 which deviates from the standard of quadratic forms.


maggot: Fair enough, everyone is entitled to their own opinions and I merely posted this to see what people would say. But in (my?) defense, if your a seasoned math/physics/engineering veteran, defining variables is half your job. The usage of Tau, imo, simplifies this process. Also, Michael Hartl was a professor of theoretical/computational physics at Caltech, I'm pretty sure grasping radian measures is the least of his worries.

y3k9: What Hartl is arguing for (the fighting you refer to), is that Tau is the more natural choice and is more readily understandable by a person who has little to no experience with mathematics (e.g. a child). The point being that, perhaps more people would be able to grasp the idea, or to take up mathematics as a hobby/profession/etc if the change were to take place.

 

[blakedacuber]

i had a thought that it was wrong

then i asked my maths tweacher why pi was 3.17 and not 3.12 etc and she couldnt answer

 

[keemy]

Yo I have actually heard this augment before but it didn't really convince me then and not now either, sorry. My problem is there are really no practical differences (just aesthetics) which doesn't warrant any actual change imo.

 

[y3k9]

i had a thought that it was wrong

then i asked my maths tweacher why pi was 3.17 and not 3.12 etc and she couldnt answer

Weird, I always thought pi was irrational and started with 3.1415... but if you say it's 3.17 I believe you because you obviously are some genius here.

 

[some1rational]

keemy: Your right, it's purely aesthetics. But the aesthetics has the advantage of being simpler (a las it's still just an opinion) from the vantage point of the unacquianted. Also it allows for an understanding of analogous ideas (quadratic forms). Anyway, if reading it is not convincing, then there is nothing I can do. I still love Pi, but I feel Tau is the better choice.

 

[BigSams]

Yo I have actually heard this augment before but it didn't really convince me then and not now either, sorry. My problem is there are really no practical differences (just aesthetics) which doesn't warrant any actual change imo.

Dude. Yes, aesthetics plays a big factor; we're human, we like pretty stuff. But on the more practical end, if the ratio of simplified to complicated formulas as a result of switching to tau is more than 1, this could make a lot of computer programs more efficient.

 

[einstein00]

ooh, we like pretty stuff! e^(i*pi) + 1 = 0 vs. e^(i*tau) = 1 + 0. Which is prettier? Does Hartl really think that adding a "+0" makes the equation more meaningful? If so, then (e + i + pi)^0 = 1! I am a genius!