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Add definitions for cycles per second #61

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tiffany352 opened this issue Jul 30, 2020 · 1 comment
Open

Add definitions for cycles per second #61

tiffany352 opened this issue Jul 30, 2020 · 1 comment
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enhancement units For issues about the unit definitions

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@tiffany352
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New base unit: cycle.
New unit: cps -> cycles_per_second -> 1 cycle / s.

@tiffany352 tiffany352 added duplicate units For issues about the unit definitions enhancement and removed duplicate labels Aug 7, 2020
@Guillawme
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About this, the unit file from Frink has interesting notes:

hertz := s^-1 // frequency
Hz := hertz
//
// Alan's Editorializing: Here is YET ANOTHER place where the SI made a
// really stupid definition. Let's follow their chain of definitions, shall
// we, and see how it leads to absolutely ridiculous results.

// The Hz is currently defined simply as inverse seconds. (1/s).
// See: https://physics.nist.gov/cuu/Units/units.html
//
// The base unit of frequency in the SI used to be "cycles per second".
// This was fine and good. However, in 1960, the BIPM made the
// change to make the fundamental unit of frequency to
// be "Hz" which they defined as inverse seconds (without qualification.)
//
// Then, in 1974, they changed the radian from its own base unit in the SI
// to be a dimensionless number, which it indeed is (it's a length divided by
// a length.) That change was correct and good in itself.
//
// However, the definition of the Hz was not corrected at the same
// time that the radian was changed. Thus, we have the conflicting SI
// definition of the radian as the dimensionless number 1 (without
// qualification) and Hz as 1/s. (Without qualification.)
//
// This means that, if you follow the rules of the SI,
// 1 Hz = 1/s = 1 radian/s which is simply inconsistent and violates basic
// ideas of sinusoidal motion, and is simply a stupid definition.
// The entire rest of the world, up until that point, knew that 1 Hz needs to
// be equal to 2 pi radians/s or be changed to mean cycles/second for
// these to be reconcilable. If you use "Hz" to mean cycles/second, say,
// in sinusoidal motion, as the world has done for a century, know that the SI
// made all your calculations wrong. A couple of times, in different ways.
//
// This gives the wonderful situation that the SI's Hz-vs-radian/s definitions
// have meant completely different things in the timeperiods:
//
// * pre-1960
// * 1960 to 1974
// * post-1974
//
//
// Thus, anyone trying to mix the SI definitions for Hz and angular
// frequencies (e.g. radians/s) will get utterly wrong answers that don't
// match basic mathematical reality, nor match any way that Hz was ever used
// for describing, say, sinusoidal motion.
//
// 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.
//
// One could consider the CGPM in 1960 to have made the original mistake,
// re-defining Hz in a way that did not reflect its meaning up to that point,
// or the CGPM in 1974 to have made the absolutely huge mistake that made
// the whole system inconsistent and wrong, and clearly broke the definition
// of Hz-vs-radian/s used everywhere in the world, turning it into a broken,
// self-contradictory mess that it is now.
//
// Either way, if I ever develop a time machine, I'm going to go back and
// knock both groups' heads together. At a frequency of about 1 Hz. Or
// better yet, strap them to a wheel and tell them I'm going to spin one group
// at a frequency of 1 Hz, and the other at 1 radian/s and let them try to
// figure out which one of those stupid inconsistent definitions means what.
// Hint: It'll depend on which time period I do it in, I guess, thanks to
// their useless inconsistent definition changes.
//
// It's as if this bunch of geniuses took a well-understood term like "day"
// and redefined it to mean "60 minutes". It simply breaks every historical
// use, and present use, and just causes confusion and a blatant source of
// error.
//
// Frink tries to follow the most authoritative international standards bodies
// for all of its definitions. However, when authoritative international
// standards bodies change definitions silently to make them inconsistent
// with their previous definitions and with centuries of fundamental
// mathematical definitions, then Frink would be negligent to not try to
// warn you of the huge incompatibilities in the strongest possible way.
//
// One of Frink's design goals is: "When in doubt, be pedantic. Explain to
// people how their calculation might be problematic and help them to write
// it in a more standardized, unambiguous way." The re-definition of the Hz
// is an actively damaging change that has to be warned about in the strongest
// possible terms.
//
// In summary: Frink grudgingly follows the SI's ridiculous, broken definition
// of "Hz". You should not use "Hz". The SI's definition of Hz should be
// considered harmful and broken. Instead, if you're talking about circular
// or sinusoidal motion, use terms like "cycles/sec" "revolutions/s",
// "rpm", "rps", "circle/min", etc. and Frink will do the right thing because
// it doesn't involve the stupid SI definition that doesn't match what any
// human knows about sinusoidal motion.
//
// WARNING: Use of "Hz" will cause communication problems, errors, and make
// one party or another look insane in the eyes of the other.
//
// 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.
//
// Hz == YOU CANNOT WIN
//
// (Insert "IT'S A TRAP" image here.)

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