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Comment by timewizard | Hacker News Reader

I present you, if you're into this sort of thing, one of the snarkiest files on the internet.

https://frinklang.org/frinkdata/units.txt

Alan's editorializing on the nature of radians and hertz is my favorite thing.

  // Beware the SI's broken definition
  // of Hz.  You should treat the radian as being correct, as a fundamental
  // dimensionless property of the universe that falls out of pure math like
  // the Taylor series for sin[x], and you should treat the Hz as being a 
  // fundamental property of incompetence by committee.

This is all quite entertaining.

This is gold.

> In other words, if you use the Hz in the way it's currently defined by the SI, as equivalent to 1 radian/s, you can point to the SI definitions and prove that you follow their definitions precisely. And your physics teacher will still fail you and your clients will think you're completely incompetent because 1 Hz = 2 pi radians/s. And it has for centuries. You are both simultaneously both right and both wrong. You cannot win. You are perfectly right. You are perfectly wrong. You look dumb and unreasonable. The person arguing the opposite looks dumb and unreasonable.

Huh? Seems this quote confuses correspondence and equivalence. A frequency f = 1 Hz = 1 s^-1 (aka cycle/s != rad/s) corresponds to an angular frequency ω = 2π rad/s (ω = 2π f) but they're distinct concepts and quantities. The Hz was introduced in SI with all those considered. Basically both statements "1 Hz = 1 rad/s" and "1 Hz = 2π rad/s" are wrong. The only dumb is this quote tbh.

The point being made in that file is really that, if you take the SI definitions literally, 'cycles' and 'radians' end up both being dimensionless and equal to 1, which is stupid.

There are other contenders if you like your snark on the ranty side.

  // At this point, I'd like to take a moment to speak to you about the Adobe PSD format.

https://github.com/gco/xee/blob/4fa3a6d609dd72b8493e52a68f31...

> // I dislike having a prefixed unit as the base reference. What a horrible decision. Why don't you just have it go to ten and make ten a little louder?

Really delightful.

That question (regarding the unit of mass, not the volume control) does apparently have an answer[1,2], and the answer (if true) is really funny: this was in fact the original plan, and the proposed unit was called the grave[3] (pronounced “grahv”). Then the French Revolution came and that name’s similarity to the word grave (count, the noble title, from German; cf. English margrave) led to it being superseded by the gram.

I don’t like the reference I have, though, so take this whole story with a grain of salt.

[1] https://phys.libretexts.org/Courses/Prince_Georges_Community...

[2] https://physics.stackexchange.com/questions/64562

[3] https://en.wikipedia.org/wiki/Grave_(unit)

Haha, wow. And he really has it in for the candela too. Thanks for pointing to this, I would never have thought to look here, but it's an excellent read.

                // Alan's editorializing:
                //   I think the candela is a scam, and I am completely
                //   opposed to it.  Some good-for-nothing lighting "engineers"
                //   or psychologists probably got this perceptually-rigged
                //   abomination into the whole otherwise scientific endeavor.
                //
                //   What an unbelievably useless and stupid unit.  Is light
                //   at 540.00000001 x 10^12 Hz (or any other frequency) zero
                //   candela?  Is this expected to be an impulse function at
                //   this frequency?  Oh, wait, the Heisenberg Uncertainty
                //   Principle makes this impossible.  No mention for
                //   correction (ideally along the blackbody curve) for other
                //   wavelengths?  Damn you, 16th CGPM!  Damn you all to hell!
                //

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