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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)

#151

Post by amalcon »

mhartl wrote: post #133
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.

This torque issue was really bothering me, and I finally realized why: I was pretty sure I'd already seen torque represented by a letter other than tau. Sure enough, I checked my copy of Introduction to Electrodynamics by David Griffiths, which is a popular (and truly great) intermediate E&M text, and there it was on p. 162: torque written as N = r X F. The same usage appears in several other places in that book, and…

Interesting. N may not be such a great symbol to use for torque, because the equation relating it to force and radius is a cross-product. In that context, N often refers to a "normal" vector. Still, it's apparently in use somewhere, which is interesting.

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

#154

Post by billybob »

Groxx wrote: post #43
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…

Except BC/AD -> BCE/CE is a label change, not a numbering change, and it's arguably for largely P.C. reasons; conforming to P.C. is the "in" thing. We in America have also changed from Indians to Native Americans to American Indians to Indigenous Peoples to whatever, and N* to Black to Colored to African American to something supposedly unoffensive while still defining the same group. http://en.wikipedia.org/wiki/Com…

I think it's ridiculous to rename dates just to remove their religious connotations, especially when the reference point is still the (slightly inaccurate) birth of Christ. If someone wanted to start with a new system, where year 0 is the Big Bang, that would be reasonable - it would put all dates on the same time scale instead of having to convert between BC and AD. But if you're going to keep the religious reference point, why pretend it's something else? Prejudice is the only reason that I can see.

Of course, when we revise our estimates of when that happened, it would screw everything up again...

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

#156

Post by techiferous »

waldrews wrote: post #142
techiferous wrote: post #107

Earlier quoted context omitted.

Your comment doesn't fit the article very well which may be why it is being downvoted. "this is more like a religious propaganda than science" First of all, it is about math, not science. And it is not like religious propaganda, which relies on authority or faith. It clearly and cogently explains reasons why using tau is better than pi. "Throughout the article they have only demonstrated how a particular community is…

Hold off on the "he is not a scientist" line... the Caltech Physics Ph.D. (a theorist, not some namby-pamby experimentalist) does give Michael the street cred to rant about such things. Now if only he used his powers for good instead of evil...

Ah, I didn't catch that. :)

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

#157

Post by JadeNB »

blahedo wrote: post #114
aspiringsensei wrote: post #65

Earlier quoted context omitted.

> 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.

"Incredibly minor": not even close. This is the very worst sort of change to have to make, because you can't do it automatically, and doing it manually is fraught with opportunities for bugs. Not to mention that the natural pedagogical order will change in several cases that a simple "translation" wouldn't reflect. A lot of CS2 books in Java---especially two or three years ago---spent a lot of time and trouble showin…

> you can't do it automatically

Why not? This seems like precisely the sort of change that you can make manually: Every π becomes (τ/2). Granted, this'll produce some weird formulæ, like `C = 2(τ/2)r`; but fixing those little problems is an excuse for still more editions. :-)

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

#158

Post by mhartl »

waldrews wrote: post #142
techiferous wrote: post #107

Earlier quoted context omitted.

Your comment doesn't fit the article very well which may be why it is being downvoted. "this is more like a religious propaganda than science" First of all, it is about math, not science. And it is not like religious propaganda, which relies on authority or faith. It clearly and cogently explains reasons why using tau is better than pi. "Throughout the article they have only demonstrated how a particular community is…

Hold off on the "he is not a scientist" line... the Caltech Physics Ph.D. (a theorist, not some namby-pamby experimentalist) does give Michael the street cred to rant about such things. Now if only he used his powers for good instead of evil...

I wasn't going to say anything, but I admit that the "he is not a scientist" line did sting a little. Although it's true that I'm not currently suckling at the academic teat, I did spend three years at the Harvard-Smithsonian Center for Astrophysics as an undergrad and eight years at Caltech as a grad student and postdoc doing research in theoretical astrophysics. I like to think that gives me some cred as a scientist, and I appreciate your coming to my defense. :-)

One reason I didn't hold the comment against the parent poster is that techiferous == Wyatt Greene, and he was by far the single most helpful pre-launch reviewer of the Tau Manifesto. He is clearly on the side of what is good and sweet and true.

Speaking of good vs. evil, you sound like a supporter of the Jedi. While it is true that I am a Sith lord, it is my duty to inform you that it is the Jedi, not the Sith, who are truly evil. How can this be? Suffice to say you've been exposed to a lot of anti-Sith propaganda. ;-)

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

#159

Post by nooneelse »

amalcon wrote: post #116
krschultz wrote: post #93

Earlier quoted context omitted.

Or you could use M for moment and stop using tau for torque. Most mechanical engineers talk about moments with M instead of tau.

The electrical engineering thing demonstrates that you're unlikely to get a particular discipline to change its own notation. It would have made much more sense in retrospect to change current to something other than i, but that's not what happened.

As an electrical engineer (by way of physics and math), I'll use any other damn letter that makes sense for current that you want, and try to sway my fellows too. I just haven't seen a good option yet. What have you got?

"c"... no good, speed of light for one; and also current needs good a good alteration for DC vs AC, "c" and "C" look too similar when written by someone else's hand (and "C" is crap in equations anyway since it can look too much like a "("). Current is a flow, but "f" is well used. Any good suggestions?

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