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A trick to eliminate 2π (sometimes)

marci.gunyho.com

1–10 of 179 posts

Re: A trick to eliminate 2π (sometimes)

#3
`Θ^i = 1` does make this really slick, imho.

I often wonder if someday when we meet alien intelligences, they'll have a completely different set of constants, derivable from our own but different. Θ=535.491... may be such an example.

Re: A trick to eliminate 2π (sometimes)

#6
Responding to this part in the article:

> I’m not entirely sure about the intuitive meaning of “taking the derivative and dividing by 2π”. Is there some sort of fundamental connection to periodic functions?

If you have a function f(x) where x is measured in radians, and there are 2pi radians per turn, then you can change variables.

Let t represent turns. One turn is 2*pi rad, and you want t = 1 when you've gone all the way around in x, so t = x/2pi.

By the chain rule,

df(x)/dx = df(t)/dt dt/dx = 1/2pi * df(t)/dt

So I think this might be the meaning you're looking for when you do the rescaling of the derivative.

You're using turns as units instead of radians. cos(x=2pi)=cos(t=1)=1, and so on.

Re: A trick to eliminate 2π (sometimes)

#9
post #6

Responding to this part in the article: > I’m not entirely sure about the intuitive meaning of “taking the derivative and dividing by 2π”. Is there some sort of fundamental connection to periodic functions? If you have a function f(x) where x is measured in radians, and there are 2pi radians per turn, then you can change variables. Let t represent turns. One turn is 2*pi rad, and you want t = 1 when you've gone all t…

FWIW they mention this in the article:

> I like this, because it kind of eliminates the need for radians: the x in usin(x) has the unit of “turns”. I think this is conceptually much simpler.

Re: A trick to eliminate 2π (sometimes)

#10

Interesting. It's probably not worth defining a new constant for exp(2π), but this is a further demonstration of the Tau Manifesto's argument that 2π is much more of a fundamental value than π.

Fundamental sounds like a value judgment. Pi is transcendental. 2 isn't. That's really the distinction. Unless there were other finite factors in pi, that is the number that's always going to have to be approximated in computation.
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