Imperial vs Metric

[bjm]

I seem to remember someone in more recent history getting himself in the doggie doodah for suggestion the earth orbited the sun.

I seem to recall the late Stephen J Gould covered this in one of his many essays - I no longer have his books - and I'm pretty sure it was only in the west that the earth-centric view held because of religious dogma? Same for the flat earth theory which, I seem to recall, only originated around the 17th century?? Any SJG readers out there?

 

[Droogs]

While at the same time all of Asia Minor and the Far East knew of and taught the solar system was helio-centric and that the Earth was a globe. Infact the shape of the Earth was never an issue as even the "church" accepted that.

We Europeans are rather arrogant, in that, because we had the Renaissance and then leap frogged the knowledge level of other civilizations 300 years ago the masses here think everyone else was rather thick and backward.

 

[Andy Kev.]

@Andy Kev.
I am totally agnostic with regard to whether there are human or non human beings that reside on some other ball of dirt whizzing about the multiverse and if they have been here or not. I see no definitive proof either way, so I do not know.

Having had a total obsession about the Sumerians (since I played the "Royal game of Ur" and Indianna Jones as a child), Akkadians and the growth of civilizations in the fertile crescent to the point that my entire secondary school subject choices were focused on being able to get to UofC and their archeology program (I just missed out on a scholarship) and unfortunately my parents could not afford to pay, so I ended up taking the shilling instead. I also had a childhood in which biblical history was rammed into my head. This only increased my desire to learn about the ancient world. I soon managed to divest myself of the superstitions but never the interest in the cradle of civilization or ti's developement.

There are a growing number of respected and acknowledged experts in various fields of academic study who are not interested in little green men at all but are postulating that in certain areas previous societies had a level of knowledge about Astronomy and Mathematics at least on a par ours as of the 1800s. Maths doesn't lie and when you look at the numbers surrounding many of the ancient worlds relics they show an amazing level of sophistication in those areas.

It is unfortunate that so many people do not believe that we human beings are capable of such thinking so long ago. More and more evidence is being found and explained from further in our past thatn ever before thanks to technology and our own growing knowledge, that shows the possibility that our ancestors weren't the troglodites they are portrayed to be. Known recorded history is only 6k to 8k years old and yet we have physical evidence of astronomically based super structures all around the world that are provably older than those records.

The people of the world in those ancient times did not think the world was a pizza on the back of a big turtle, they were perfectly aware it is a globe and of its position in the solar system and they dynamics of it's relation with the other "heavenly" bodies.
Man in his current physical state of being has had the same brain structure and reasoning pattern for over 200 000 years by the latest level of our knowledge. Do you seriously think that they were all running around with an IQ at the level of a moron no there will have been some pretty smart cookies around who would have worked things out. We know that civilization tends to grow around coastal regions We are becoming more aware that over the last 12 - 15K years we have lost a coastline equal to China in size due to global events. We know that sea levels rose over 400 feet in a geologically minute time period of a couple of centuries around 12k years ago for definite fact, they are just arguing over the cause. That surely must have have a major devastating impact on our ability to pass on our sum total of human ken to the next generations and sunk proof of our passing below a level we could easily reach until today.

Nothing to do with aliens or crop circles or any other such bovine poo. Just the acknowledgement that our predeccessors were probably a hell of a lot smarter than we in our arrogance give them credit for.

I was only being lighthearted ... honest!

Actually, I'd heard about the sea level rise thing and about sunken cities off the coast of India which would, of course, have once been coastal cities.

I don't have any difficulty in accepting that ancient civilisations could have been hot on the astronomical front. Theoretically if you can accept that 1 +1 = 2, you should by dint of much effort and loads of genius be able to work your way up to E = m x c squared (can't work out how to write formulas on this forum), simply because maths seems to be so chillingly absolute and of course pure maths is independent of physical observations and only dependant on a writing implement and something to write on.

The problem is, as you point out, of our time. The gap in our knowledge about ancient times has the alien theorists rushing in to fill the gaps. Their reasoning seems to be along the lines of, "I can't imagine them being that advanced, so they must have had alien help". A falser case of logic you couldn't imagine. The only thing that I know of that even remotely works in the favour of these people is an African tribe which allegedly has knowledge of a star that you can't see with the naked eyed.

FWIW I'm convinced that there are many inhabited planets out there and statistically it is highly likely that at least one of them works in inches and plays rugby.

 

[Droogs]

let's hope so

 

[Andy Kev.]

let's hope so

Are you sure you hope so?

Can you imagine the 6 Nations plus 1 planet tournament when it turns out that all the Blxxrgaglians are at least 7' 3" and weigh 22 stone?

 

[Droogs]

that only gives them a 6" height advantage my lot has them beat everywhere else

 

[Andy Kev.]

 

[Felix]

Anyway, I'm not sure that I'd want to have intergalactic contact with somebody who doesn't get inches.

But they might come in handy if you've got a big lump of timber to move around the workshop.....

 

[raffo]

The Mayas and their predecessors invented a mathematical system in base 20. They also invented the concept of zero and developed a pretty sophisticated mathematical system. They also had a pretty advanced astronomical knowledge. On top of that they also developed a writing system. Unfortunately, religious zeal compelled the Spaniard priests to burn every Mayan written document they got their hands on.

In Peru, the Nasca civilization left very large symbols and geometrical figures in the desert. The archaeologists studying them claim they represent constellations or some astronomical representation. Unfortunately, the inhabitants of that part of South America didn't develop a writing system and their knowledge has been lost.

Regarding the Babylonians, isn't it amazing that we're still using a system developed to track time that is probably 4 or 5 thousand years old.

Another thing to wonder, just about 100 years ago the common consensus was that our Milky Way was the all there was, that was the universe. The discovery of galaxies and the size of the universe is amazing if one thinks about. I even remember mentions of the "Andromeda nebula" in the 70s, old names are hard to change.

 

[Andy Kev.]

If you look at any of the pictures of spiral galaxies, like the Andromeda, just hanging there in space and if you even try to envisage the sizes involved, it is quite mind boggling.

And they measure them in light years which is cheerfully non-metric.

 

[Felix]

If you look at any of the pictures of spiral galaxies, like the Andromeda, just hanging there in space and if you even try to envisage the sizes involved, it is quite mind boggling.

And they measure them in light years which is cheerfully non-metric.

Isn't the speed of light something like 3 x 10**8 metres per second multiply that by 3.157 x 10**7 (number of seconds in a year) the answer to which looks like a metric number <lol>

 

[Andy Kev.]

Isn't the speed of light something like 3 x 10**8 metres per second multiply that by 3.157 x 10**7 (number of seconds in a year) the answer to which looks like a metric number <lol>

Ah but … the speed of light is an absolute, a bit like a piece of wood: the units in which you choose to measure it- let us compromise on a piece of wood flying through the workshop at less than the speed of light due to frustration at mangling some dovetails - are entirely arbitrary i.e. anything but absolute.

Gotcha! ( er … I think.)

Come to think of it, the number of seconds in a year isn't very metric either.

 

[Dr Al]

Ah but … the speed of light is an absolute, a bit like a piece of wood: the units in which you choose to measure it- let us compromise on a piece of wood flying through the workshop at less than the speed of light due to frustration at mangling some dovetails - are entirely arbitrary i.e. anything but absolute.

Gotcha! ( er … I think.)

Come to think of it, the number of seconds in a year isn't very metric either.

The second is metric† though. The number of metres in the length of my workshop isn't what I think you're calling "very metric", but the metre is.

† In the sense that it's one of the SI units

 

[Andy Kev.]

The second is metric† though. The number of metres in the length of my workshop isn't what I think you're calling "very metric", but the metre is.

† In the sense that it's one of the SI units

I'm glad you got that little footnote in. It's a get out clause worthy of a politician! And I do admire the sheer audacity of it.

The following is to be taken with caution as it is a long time since I did any physics at school: units of time are anything but metric as their start point is the number of days which the earth takes to go around the sun (365 and a bit). That is very unmetrically divided into 12 months, each with differing numbers of days. However, a day is always 24 hrs (although doesn't it change every few thousand years due to speeding up or slowing down of the earth's rotation?) and then we chop that down to the second in the fashion with which we are all familiar.

Thereafter the scientists treat the second metrically , milli-, micro, nano- etc etc. for the simple reason that doing their sums would lead to a lot of headaches if they didn't.

The metre itself is by definition metric. It is also by definition arbitrary. Didn't they kick it off by saying, "Right we've got this bar of platinum in a shed in Paris and we're saying that it is a metre long i.e. it's the reference standard for the metre". There is of course nothing intrinsically significant to that length of bar, hence its arbitrariness. And if I remember rightly, no matter how much you try to control the temperature at which it is stored, it is likely to expand or contract by a micromilliwobble every now and then. Didn't they then adopt a different definition based on a true absolute constant, probably measured according to something or other in a vacuum?

Imperial is also of course arbitrary: "How long's the King's foot?" "Er … that long." "Right, as of now, that's a foot."

The beauty of imperial is that it then uses divisions and multiples of feet in human terms e.g. a furlong is a furrow long (if memory serves that's the length of a ploughed furrow and it comes in at 220 yards). What this adds up to is that imperial has a very pleasant, villagey feel about it whereas metric is perfect for the cold, unimaginable distances of the cosmos and the equally unimaginable tiny spaces within atoms. It's sort of the difference between enjoying a pint while watching a cricket match on the green versus downing a mineral water while discussing this year's accounts.

Mine's a Guinness.

 

[J-G]

Didn't they kick it off by saying, "Right we've got this bar of platinum in a shed in Paris and we're saying that it is a metre long i.e. it's the reference standard for the metre".

NO.

Quite the opposite. The original definition of a Metre was 1 10millionth of the distance from the Equator to the North Pole along a Great Circle. The conversion to a Platinum Rod came later simply for the convenience. It is now defined in terms of the speed of light which is an absolute constant not subject to variation due to temperature or anything else.

You also have the definition of Time the wrong way round. The SECOND is the basic SI unit of time which is now defined in terms of the frequency of vibration of a Caesium-133 atom.

 

[Dr Al]

...

units of time are anything but metric as their start point is the number of days which the earth takes to go around the sun (365 and a bit). That is very unmetrically divided into 12 months, each with differing numbers of days.

...

Thereafter the scientists treat the second metrically , milli-, micro, nano- etc etc. for the simple reason that doing their sums would lead to a lot of headaches if they didn't.

You seem to be picking on one part of the meaning of the word "metrically" - the use of "metric prefixes" like nano. You can use metric prefixes with any system (look at the thou for an example - effectively one milli-inch). That is only one part of the metric system; another very important one being the concept of Coherence, which to my understanding basically means that you very rarely need arbitrary constants when performing calculations. For example, a watt is one joule per second whereas a horsepower is 550 foot-pounds per second.

The second as a unit is metric in the sense that it is a fundamental part of the metric system of units known as SI and is coherent with the other metric units. It is now defined in terms of things that don't change anywhere in the universe, as are all elements of the metric system (and other elements like the inch that are defined in terms of the metric system).

All units are arbitrary in that you have to pick a number to start with. The fact that the metre was initially picked as a (not very accurately measured) part of the earth's circumference, the second was picked as part of a day and the foot was picked as the length of someone's foot is irrelevant. The derived units are arguably more important as things like the watt are simple whereas things like horsepower need conversion factors.

Imperial units might well be better for measuring furrows but for most things that any of us are going to use in a workshop, there's no fundamental difference in what the two systems are capable of. The inch and the millimetre are based on the same standard (the metre) after all. Whether you prefer working to millimetres or 1/32", or prefer microns or ten-thousandths of an inch is arguably personal preference, although having multiple systems of units in the world (and even just in this country) makes things more difficult for everyone.

The metric system is objectively better for scientific use and having two systems undoubtedly increases confusion, as does the imperial system's habit of switching between fractions and decimals arbitrarily - I've seen mechanical drawings with instructions like 'drill with a #6 drill, then bore to 0.240", then ream 1/4" '. I for one would much rather see 'drill with a 5.2 mm drill bit, then bore to 5.8 mm, then ream 6 mm". Similar comments can be made about material thicknesses in AWG or SWG. I would be much more in favour of inches if they were used consistently.

One thing I will say in favour of imperial stuff is that quite a few of the imperial conventional sizes (with lots of exceptions of course) are slightly bigger than the metric equivalents. That means if I buy a bit of 1" stock and stick it in the lathe, I can turn it down to 25 mm and guarantee concentricity with diameters. If I'd bought 25 mm stock, that wouldn't be possible!

I also think there's a special place in hell reserved for people who quote temperatures only in Fahrenheit...

Mine's a Guinness.

I'll have 50 ml of Springbank.

 

[Droogs]

Your all wrong. You are confusing and conflating Decimal and Duodecimal numbering systems. 1m is metric no matter what number base is used to name or compare it. I think the problem first occured during the 70's for most brits as both metrification and decimalisation were happening at the same time

@J-G I think you will find that constant is relative, especially once over the event horizon of a black hole

 

[AES]

Erm ................. what about the nautical mile and the (attached) knot - nautical miles/hour - then?

Mind you, I'm just a simpleton, so the idea of a horse raising a pound of something over a foot seems nice and simple to me - but no idea if the original horse was "calibrated" or not (or even if he was measured before or after the poor creature had just had his oats + a sugar lump)!

But as said, I'm just a simpleton, so you can keep all your beery and watery stuff thanks - mine's just a goodly-size (Imperial or Metric, I don't care) of Malbec.

 

[AJB Temple]

Please can someone now tell me something useful to put my mind at rest. I would like to get my head around what was there before the (assumed) Big Bang. Also how can I imagine infinitesimal space? I feel this is sucking me in.

 

[Andy Kev.]

You learn something every day.

@ J-G I'd not heard the equator to N Pole thing before and that is of course also necessarily arbitrary. Agreed about basing the metre on the absolute constant of the speed of light (in a vacuum?) but am I not right in thinking that it still does no more than precisely define in absolute terms the the length of the arbitrary metre. We could just as easily determine the foot in terms of the speed of light but it would be no less arbitrary. I'm not suggesting that arbitrary is in any way inferior but the more I think about it, the more arbitrary units of measurement seem to be unless the unit of measurement is itself an absolute e.g. the mass of a proton.

@Dr Al I agree with all of that. I do however, have the impression that metric is presented as being somehow superior. It can't be of Course, as we agree that all units of measurement are arbitrary. What it undoubtedly is, is mathematically more convenient, especially for physicists, engineers etc. The woodworker has a choice of which system he finds to be more convenient. I tend to prefer imperial for woodwork because it seems natural to consider halves, quarters, eighths of units (in this case the inch) for practical purposes. Obviously other people prefer metric. I was brought up with both systems and have come to prefer imperial for the real world and metric for when e.g. I'm trying to understand astronomy or nuclear physics.

Isn't the real problem time? (Genuine question.) We're not quite sure what it is and it is - almost incredibly - relative due to the famous speeding up/slowing down aspects of it for high speed space travellers.

@Droogs I refuse to offer an opinion on black holes until I've heard Paul Sellers on the topic. Also Einstein was not known for his mortices and tenons which does of course cause the thinking man to raise an eyebrow.