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No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

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Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#71

Post by sophacles »

rick_2047 wrote: post #20

I may get down modded for this but I just have to say, this is more like a religious propaganda than science. Throughout the article they have only demonstrated how a particular community is more comfortable with using double pi. I totally believe in what wwortiz said in his/her(sorry cannot open your website) post. If they like the tau so much they should be writing papers on its advantage. I think scientists should…

Look at it like a refactoring. Sometimes it is desirable to stop and reorganize a bit. The fact that there is a good reason for using both pi and tau may not be immediately obvious to some people, so they tell us about it. I for example, would never catch on to what tau is, and why it is useful without this. Now that I read it however, I can understand it well. Further, I have gone back and re-examined some things I have been learning lately that contain major sin and cos components. Suddenly they make much more sense to me -- using Tau gives me an intuitive understanding of how cos and sin are related.

To put it another way: If I, and other willing but not genius types, can't understand the results of scientists "finding and confirming important things" why should they do it in the first place? [Edit:] I mean can't understand in a way for use in engineering and other practical ways.

A final note: there is a strong resistance in the math, science, and engineering communities to the idea of "lets look at what we know and reformulate it in a consistent way". They think it is intuitive as it is, even tho there may be ways that people can learn it faster and to as deep of an understanding if a different formulation is used. This results in a lot of stupidity in the world like teaching physics in the order it was discovered, rather than some order building on concepts, or teaching physics by expressing velocity as a fundamental concept instead of as a derivative of something else.

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#72

Post by est »

steveklabnik wrote: post #61
est wrote: post #52

Earlier quoted context omitted.

> The term you're looking for is 'irrational.' I think by infinite he means non-terminating. Conversely, an irrational number always has a non-terminating non-repeating decimal representation.

You're technically correct, the best kind. I'd argue, however, that 'irrational' is closer to what he meant, than the exactness of what he said. Any time you move between a layman's understanding and a detailed technical one, the abstraction can leak. I think 'irrational' matches up with intuition better, even if it's described as 'non-terminating.' People don't talk about 2/3 in the same way they talk about π.

> I think 'irrational' matches up with intuition better, even if it's described as 'non-terminating.'

well, counter example, 1.22333444455555..... is an irrational number, but it's somehow easy to understand rationally. LOL

Also it's worthy point out decimals are heavily related to positional notation. Another fun example is we can use base-e number system for maximum calculation efficiency. Or better, base-tau. So 6.28 in base10 equals 1 in base-tau numeral system.

see:

http://en.wikipedia.org/wiki/Non-integer_representation#Base...

http://en.wikipedia.org/wiki/Factorial_number_system

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#73

Post by mhartl »

amalcon wrote: post #38
tc wrote: post #2

Perfect; to my lisp startup file was just added: (defconstant tau #.(* 2 pi)) Regarding adoption, I think it's worth pointing out that these sorts of conventions can and do shift within a generation. I recall quite clearly while growing up the convention for indicating years = the year one [1] was B.C. and A.D. It seems like over the past few years we've definitively decided on B.C.E. and C.E. instead [2]. All it rea…

I have no problem with people trying to do this in principle. I really don't care enough, but other people can. The symbol "tau", however, is an especially poor choice for a trigonometric symbol, because it's also used for torque. You won't get many physics teachers to change over if every time you try to calculate a torque from a force and radius, you run into a symbol conflict.

I mention torque in the manifesto, but I wasn't specific enough in this case, and I've added an example addressing this issue at http://tauday.com/#sec:four_arguments. The short version is that when necessary you can easily add a subscript to avoid ambiguity, such as tau_R for rotational torque. (Superscripts work, too. Particle physicists deal with pions, which are represented by the letter pi, but all the symbols have superscripts indicating their electric charge. As a result, no one ever confuses them with the number.)

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#74

Post by nopassrecover »

aspiringsensei wrote: post #65
JeanPierre wrote: post #29

Part of me is saying yes, part of me is saying no. Let me elaborate: It makes all sense that tau should be the number used INSTEAD of pi: It simplifies things even more. (I hope I'm not the only one tired of writing 2*pi in papers.) But that doesn't make pi WRONG: It's defined by C/D, and the formulas make perfectly sense, even though you have to multiply by 2. Besides, it would mean a total rewrite of a lot of paper…

> total rewrite of a lot of papers, including a lot of mathematical books. Somebody at the textbook publishers is smacking their lips at the prospect of selling an entirely new edition with an incredibly minor change.

Doubt it, they release annually anyway.

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#75

Post by acangiano »

JadeNB wrote: post #12
acangiano wrote: post #9

Earlier quoted context omitted.

It's real (see my blog post about it: http://math-blog.com/2010/06/28/forget-pi-here-comes-tau/ ).

Note that your equality \(e^{i\tau} = 1\) implies only that \(e^{i\pi} = \pm1\), hence is strictly weaker than Euler's equality (which picks a sign). I think that you might have meant \(e^{i\tau/2} = -1\). (Is there a way to do LaTeX properly here?)

I was actually reporting the equality as expressed by the manifesto. See here: http://tauday.com/#sec:euler_s_formula

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#77

Post by edanm »

rick_2047 wrote: post #20

I may get down modded for this but I just have to say, this is more like a religious propaganda than science. Throughout the article they have only demonstrated how a particular community is more comfortable with using double pi. I totally believe in what wwortiz said in his/her(sorry cannot open your website) post. If they like the tau so much they should be writing papers on its advantage. I think scientists should…

"Throughout the article they have only demonstrated how a particular community is more comfortable with using double pi."

The manifesto explains why using tau is better mostly for non-mathematicians. Especially, but not limited to, children learning about radians for the first time. You may disagree, but I think helping explain mathematics better is incredibly important.

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#78

Post by jcsalterego »

Naga wrote: post #68
steveklabnik wrote: post #51

Earlier quoted context omitted.

Ugh, I know this is slightly offtopic, but there's nothing more I dislike than B.C.E and C.E. I can understand not trying to promote a Christian-centric worldview, but by only changing the labels, they accomplish nothing. Now, the birth of Christ sets a 'common era,' which arguable makes it _more_ 'offensive' than just acknowledging what happened on that particular day.

There is another dating system which aims to get around this, by actually changing the numbers, which is called Before Present (BP). It sets 0 to be January 1, 1950, as an arbitrary date of the present. So, 1500 BP is 450 AD. I see it used most often it dealing with archaeology.

Unix epoch had it right. Let's just all count seconds before/after 1 Jan 1970.

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#79

Post by amalcon »

Groxx wrote: post #58
amalcon wrote: post #38

Earlier quoted context omitted.

I have no problem with people trying to do this in principle. I really don't care enough, but other people can. The symbol "tau", however, is an especially poor choice for a trigonometric symbol, because it's also used for torque. You won't get many physics teachers to change over if every time you try to calculate a torque from a force and radius, you run into a symbol conflict.

How many symbols aren't in use, though? If you've got a notably better one, the "manifesto" may consider changing, but they seem (to me) to have pretty good reasons for choosing tau.

I'd ideally prefer to pick one that isn't used in angular things. Because non-English, non-Greek glyphs are somewhat underused for this sort of thing, and because of visual similarity to pi, I'd suggest the hebrew Het or Russian л. However, I really have no problem with continuing to use the multi-glyph symbol 2pi.

Re: No, really, pi is wrong: The Tau Manifesto (Tau Day, 2010)

#80

Post by edanm »

I really hope this convention gains wide adoption. It's pretty obvious to me that it just makes mathematics make more sense, at exactly the time when it needs to make more sense (people learning maths in high school).

Until then, here's the trick I'm using: whenever I need to use pi, especially when it comes to the unit circle and radians, I'm just going to do it in terms of tau, then convert at the end. I just wish I'd have understood this before I finished my degree :)

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