Festool Owners Group
OFFTOPIC => General Friendly Chat => Topic started by: smorgasbord on May 28, 2022, 06:45 PM

A fun bit of history on the definition of a meter: https://www.nist.gov/siredefinition/meter

Restarted this topic without the political content. Lets keep it that way.
Thanks,
Seth

Sheesh. Why couldn’t they just use a tape measure?
[attachimg=1]

LOL, they couldn't round that up to 1,650,754 ? [big grin]

LOL, they couldn't round that up to 1,650,754 ? [big grin]
Ya Bob they could...but then they'd be .27 wave lengths off and we now know what kind of serious issues that would present. [smile]

Sheesh. Why couldn’t they just use a tape measure?
I think it's interesting that the original definition was simply the length of a platinum bar kept in a climatecontrolled basement in France. Problem was, anyone who wanted to ensure their meter bar/tape/whatever was correct had to go to great pains to get access to that hunk of platinum. And imagine trying to hold something up to that bar and dropping it or otherwise hitting it hard enough to change its length by even the slightest!
Then, in 1875, they made a new bar. This one had an "X" crosssection and instead of it being the exact length, it was longer but with two scribed marks to indicate the meter length, which had to be measured at the melting point of ice and standard atmospheric pressure. They also made 30 official copies that were distributed to enable companies to measure against them, somewhat more easily. The current standard is something that anyone with enough money can reproduce, so there's no dependence on a single source of truth anymore.
What cracks me up is that originally the meter was supposed to be 1/10,000,000 of the distance between the North Pole and the equator, but they screwed that up and so the real definition of a meter is actually 0.2mm shorter than it should have been. It's actually too bad that the meter wasn't defined as a whole number divided by the speed of light in a second. Then, for instance, the speed of light in a vacuum could simply be 300,000,000 meters per second.

It's actually too bad that the meter wasn't defined as a whole number divided by the speed of light in a second. Then, for instance, the speed of light in a vacuum could simply be 300,000,000 meters per second.
That problem only occurs because a second is a crooked unit, stemming from the earth refusing to rotate around the sun each 100 selfrotations [wink]

Well, that's just silly, almost as dumb as a foot being literally the King's foot. Then changing it when the king changed?
Of course, it was decades ago, but I thought I remembered something from school about the meter being based on something simple? This made it better, along with the simplicity of the base 10.
I wonder why the "foot" was divided into 12 segments? It could have been 10 and maybe some of this would never have happened.

“I wonder why the "foot" was divided into 12 segments?‘
12”=12 months? 1”=1 month?
At least they didn’t make a 1/4”=1 week [tongue]

Well, that's just silly, almost as dumb as a foot being literally the King's foot. Then changing it when the king changed?
Of course, it was decades ago, but I thought I remembered something from school about the meter being based on something simple? This made it better, along with the simplicity of the base 10.
I wonder why the "foot" was divided into 12 segments? It could have been 10 and maybe some of this would never have happened.
Blame the Romans.
https://en.wikipedia.org/wiki/Inch
The inch (symbol: in or ″) is a unit of length in the British imperial and the United States customary systems of measurement. It is equal to 1/36 yard or 1/12 of a foot. Derived from the Roman uncia ("twelfth"), the word inch is also sometimes used to translate similar units in other measurement systems, usually understood as deriving from the width of the human thumb.

I wonder why the "foot" was divided into 12 segments? It could have been 10 and maybe some of this would never have happened.
I think it's because fractions came first and so the number 12 could be divided in half, in thirds, and in fourths using "whole" numerators. The number 10 just goes in half, or fifths which is much less commonly needed and 12 gave us sixths anyway.
Decimals weren't in any real use until 1585 when Simon Stevin published a book. Heck, the US didn't adopt decimal currency until 1792.

I wonder why the "foot" was divided into 12 segments? It could have been 10 and maybe some of this would never have happened.
I think it's because fractions came first and so the number 12 could be divided in half, in thirds, and in fourths using "whole" numerators. The number 10 just goes in half, or fifths which is much less commonly needed and 12 gave us sixths anyway.
Decimals weren't in any real use until 1585 when Simon Stevin published a book. Heck, the US didn't adopt decimal currency until 1792.
I have heard this before, but it sure seems more simplistic to deal with 10?

After reading all that I feel pretty much defeeted and in need of a pint [big grin]

I wonder why the "foot" was divided into 12 segments? It could have been 10 and maybe some of this would never have happened.
I think it's because fractions came first and so the number 12 could be divided in half, in thirds, and in fourths using "whole" numerators. The number 10 just goes in half, or fifths which is much less commonly needed and 12 gave us sixths anyway.
Decimals weren't in any real use until 1585 when Simon Stevin published a book. Heck, the US didn't adopt decimal currency until 1792.
I have heard this before, but it sure seems more simplistic to deal with 10?
Blame the Sumerians, it is why there are 12 hours on the clock as well: https://en.wikipedia.org/wiki/Sexagesimal

After reading all that I feel pretty much defeeted and in need of a pint [big grin]
That's bad... [eek]

Blame the Sumerians, it is why there are 12 hours on the clock as well: https://en.wikipedia.org/wiki/Sexagesimal
Since you brought up time, have you heard or seen anything about the "new" calendar that has been proposed?
The idea IIRC, it that every month would be 30 days. Then the "extra" days, 4 or 5 depending on the leap year thing, would be a separate "week" would make it so that the first of the year would always be on the same day. It would also follow that every other date would be the same day of the week. It would never change. Some even suggest that this be "time off" for everyone.

LOL, they couldn't round that up to 1,650,754 ? [big grin]
The 0.27 wavelength rounding might seem trivial, but recently an experiment confirmed Einstein's equivalence theorem (that acceleration and gravitation are equivalent) to an accuracy of 1 part in 10^14! The rounding you suggested is about 17 million times larger than the precision of the Einstein experiment. While units like meters, seconds and kilograms are necessarily arbitrary, the precision with which we establish them sets limits on the precision of experiments to understand how the Universe works.

... It would also follow that every other date would be the same day of the week. It would never change...
And then a great many people (most I'd guess) would never get to have their birthday on a weekend, when they (and their friends) would be away from work without taking holiday leave... seems a touch harsh!

... It would also follow that every other date would be the same day of the week. It would never change...
And then a great many people (most I'd guess) would never get to have their birthday on a weekend, when they (and their friends) would be away from work without taking holiday leave... seems a touch harsh!
Or never have a birthday, if they were born on the 31st...
Imagine always having St Patrick's Day on a... Wednesday? Most of the world wouldn't care, but the alcohol lobby in America might have some words...

LOL, they couldn't round that up to 1,650,754 ? [big grin]
Everyone takes my rounding comment above so seriously. did you notice the big grin on the end there?
It's a joke son; as Foghorn Leghorn would say.

[attach=1]

(Attachment Link)
I prefer weights to volumes when baking. It's a tossup for other types of cooking.
My coffee prep is done by metric weight for solids (beans), and US volume for liquids (water).
YMMV (or YkmMV)

...
It's actually too bad that the meter wasn't defined as a whole number divided by the speed of light in a second. Then, for instance, the speed of light in a vacuum could simply be 300,000,000 meters per second.
That would be of little use  you cannot /practically/ measure that in a planetary setting. Like on Earth. Having a true vacuum for a start and being able to measure the light speed in the chamber are anything but easy, if possible at all. You would need to measure the distance at a practical scale, NOT to preciseestimate its Limit (which is enough for everything else ref. Light).
This was restandardised only in the 1960's because a hard requirement was a BETTER accuracy and BETTER reliability than the (physical) standardbased approach provided. And the equipment able to provide that came along only in the 50s. So it took the better part of two centuries and a huge development in physics understanding and instruments to beat the original mechanicsbased approach.
Besides, the whole point of a "meter" was that it was a set standard with a formal calibration chain established and international agreements to support that. That was and is the gamne changer. The particulars are just a practicality. The "new standard rod" being made in 1875 was no accident  it was the result of negotiations making the SI system of units trully international which required each major SI member had their own "secondary" rod or two.

Robs thoughts on why he prefers the Imperial system.
http://www.youtube.com/watch?v=ZRxs23h3wro

TLDR:
He is right for himself, but is IMO doing actual harm to others by pushing HIS limited situation as if it was a general woodworker's situation. And bending arguments to push that narrative  like having a crappy scale on a tape measure or claiming Imperial is base12 which is clearly is not etc. etc.

IMO that video well explains how someone raised on a base2 (yes, 1/2, 1/4, 1/8 .. is a base2) combined with a base12 mid layer and a base 10 highest layer would justify promoting this to those who are sitting on the fence still.
I am sure that FOR HIM  an artisan of sorts  IT WORKS^{(TM)} so why change? And he is right FOR HIMSELF.
The thing is, assuming cabinetryonly and NO INTERACTION with outside world BOTH inches and centimeters work JUST FINE.
This is especially tue for a bespoke/artisan furniture maker where dimensions are secondary as there is expected to be free space around that and that standalone piece. Effectively, it is closer to painting pictures for a gallery than manufacturing of today. Ever heard a gallery asking for a specific picture size down to a millimeter (1/32") ? I did not. But I heard a lot of cases where furniture is first utilitarian and one wants it to fit exactly with even less than a mm tolerance allowed.
There, a base10 system starts making a LOT more sense. It allows a precise and EASY capture of dimensions using the least amount of characters and in a unified manner. From the road builder to the drawer maker.
Definitely more sense that a base2 system using fractional notation(!) intertwined with a base12 using a base10(!) notation.
If inches were respresented in 0/1/2/3/4/5/6/7/8/9/A/B (i.e. base12 positional notation) and base 12 was used also for fractions of inches so you would have 1.2" meaning 1+2/12 inches THEN all his arguments would be valid. But that is not how the Imperial system is structured, is it?
Ah, and do not get me started on the "base3" yards and "base1760?!?" mile.
So lets see, we have these units and notations in Imperial system:
=========================================================
base2 with decimalpositionalinsidefractional(!) notation for smaller than an inch:
^{(1127)/128} *2 > ^{(163)/64}" *2 > ^{(131)/32}" *2 > ^{(115)/16}" *2 > ^{(17)/8}" *2 > ^{(13)/4}" <*2> ^{1/2}"
base10 with decimal(!) positional notation for inches:
(112)"
simple for feet:
(13)'
base10 with decimal positional notation (huh ?!) for yards (1760 == 2*2*2*2*2*5*11(HUH?)):
(11759)y
base10 with decimal positional notation for miles (finally, partial sanity returns):
(1) miles
So 2 different(!) butalternating systems of notation in just the length description but with (4!) different/possible multiplications between the data.
So, lets see, how to describe a certain /arbitrary/ length in various Imperial units:
7 miles 1181 yards 1' 2^{45/128}"
notation: decimal positional, then /1760 and decimal positional, then /3 and simple, then /12 and decimal positional, then decimal positional inside base2 fractional
13501 yards 1' 2^{45/128}"
notation: decimal positional, then /3 and simple, then /12 and decimal positional, then decimal positional inside base2 fractional
486050^{45/128}"
notation: decimal positional, then decimal positional inside base2 fractional
=========================================================
See the problem? The more bigger /or smaller/ units are used, the LESS legible the notation gets as 3 different notations are seen in a single length note.
The real issue being that only the "full" notation  aka the most complex  results in a legible result.
And now lets do the same in the SI system:
=========================================================
base10 positional notation:
... (1999)um *1000 > (19)mm *10 > (19)cm *10 > (19)dm *10 > (1999) m *1000 > (1+) km
Example from above:
12 345 678,9 mm
notation: decimal positional, base10
1 234 567,89 cm
notation: decimal positional, base10
123 456,789 dm
notation: decimal positional, base10
12 345,6789 m
notation: decimal positional, base10
12,3456789 km
notation: decimal positional, base10
=========================================================
As can be seen from above, one can use even the km unit pretty efficiently to note <mm lenghts as the legibility is maintaned courtesy of the fractional positional system /that it is decimal is just an accident here/.
Sure, the example is an extreme. But it shows that while Imperial is generally "good enough" when used in a certain limited field  like cabinetry where one can stay within "inches" all the time  it just does not scale up nor down. So calling it "better" is just absurd.
A TRUE base12 system COULD be better. But the last time this was actively used was like 500 years ago before positional notation came to the "West". Ah, and base60 was cool too, just lately, like 5000 yrs ago in Babylon. Not Babylon 5, mind you!

"And he is right FOR HIMSELF."
And Rob says as much more than once in the video.
My opinion is his primary goal is he's found a topic to create a video around and grab a few thousand views.
Who knows maybe he's a member of this forum and saw all the babble in this thread and thought "I could spin a video around that".
If his reasoning happens to work for someone else well OK, if not to each his own.
Does he do the internet a disservice by voicing his opinion? I don't think so. He is giving his view on the subject though as you claim his math is flawed, but he is not trying to convert anyone. Only a weak mind would be bent by his words.

I prefer weights to volumes when baking. It's a tossup for other types of cooking.
Actually baking is considered a science so precise weights need to be used, however cooking is considered an art because ingredients can be changed by the cook, so volume measurements are "good enough".

... Only a weak mind would be bent by his words.
Heh, I guess I post for the weak minds then.
Seriously, the only thing thta triggered me was him arguing about the base12 and related as it is false to the point it is THE issue with Imperial lengths.
At same, this "math thing" is all sufficiently abstract that your average gal or guy trying out stuff and watching guys like him will take it as presented. People just "ate it along with the spoon" ... just check the comments to that video.
Unseriously, no one should take this too seriously to begin. Just wanted to "put up" the math behind as this topic is as appropriate for such a rant as it gets.
Ended with B5 for a reason.
[cool]