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Rod Renshaw10/01/2017 10:54:51
10 forum posts

I understand the word "exactly" is used in scientific and technical calculations to advise or remind readers that the unit being used is defined as that number in another set of units.

For example, the inch used to be defined by its relationship to the Imperial Standard Yard ( A metal bar kept in a bank vault somewhere.) and it was approximately equal to 2.54 cm But the exact conversion factor was a long decimal which changed a small amount from time to time for esoteric reasons.

Now the inch is defined as 25.4 mm (exactly) and the Standard Yard has been relegated to history. Which is a pity in some ways but at least it simplifies calculations and brings certainty. It's probably academic as far as we are concerned but some scientific calculations and measurments are done to levels of accuracy and numbers of significant figures which are far beyond anything needed in other fields.

Jon Gibbs10/01/2017 11:40:52
449 forum posts
Posted by Rod Renshaw on 10/01/2017 10:54:51:

It's probably academic as far as we are concerned but some scientific calculations and measurments are done to levels of accuracy and numbers of significant figures which are far beyond anything needed in other fields.

Yes but the most splendid irony IMHO is that the inch is now defined in terms of the metre

Jon

V8Eng10/01/2017 12:49:17
883 forum posts
1 photos

I have noticed on TV that the term "almost exactly" is used quite often, now that is a definition to conjure with!

Must get out more and away from the TV,

Edited By V8Eng on 10/01/2017 13:04:14

SillyOldDuffer10/01/2017 13:35:40
991 forum posts
202 photos
Posted by Jon Gibbs on 10/01/2017 11:40:52:
Posted by Rod Renshaw on 10/01/2017 10:54:51:

 

...

Yes but the most splendid irony IMHO is that the inch is now defined in terms of the metre

Jon

Even more splendidly ironic is just how long ago defining Imperial measure in terms of metric began.

The US did it in 1893 and the UK followed in 1898. The Canadian proposal to make the inch 25.4mm, called the "Industrial Inch" to differentiate it from all the other inches, was adopted by the British in 1927, with the US moving to the same definition in 1933.

Most recently the yard was redefined in 1959 to be 0.9144 metres exactly. There are still 25.4mm to the inch.

Dave

.

 

Edited By SillyOldDuffer on 10/01/2017 13:39:08

Jon Gibbs10/01/2017 14:07:37
449 forum posts

...and our sovereign pre-EU parliament defined the pound as 0.45359237 kg in 1963.

...and the gallon is defined as 4.54609 l.

Jon

Ajohnw10/01/2017 14:08:26
3641 forum posts
160 photos
Posted by V8Eng on 10/01/2017 12:49:17:

I have noticed on TV that the term "almost exactly" is used quite often, now that is a definition to conjure with!

Must get out more and away from the TV,

Edited By V8Eng on 10/01/2017 13:04:14

indecisionMaybe they have been watching the physics programs they put out at times and some have covered Schrodinger. Bound to have just been on the cat though so they must have read or heard more.

John

-

Dod11/01/2017 21:44:07
114 forum posts
7 photos

I think I will stick with my midgies whisker, ba hair, snoot o me bunnet and twa dreel spangs.

Must be merican terms as the English spel cheker doesn't recognize a lot of that.

V8Eng11/01/2017 22:00:04
883 forum posts
1 photos
Posted by Ajohnw on 10/01/2017 14:08:26:
Posted by V8Eng on 10/01/2017 12:49:17:

I have noticed on TV that the term "almost exactly" is used quite often, now that is a definition to conjure with!

Must get out more and away from the TV,

Edited By V8Eng on 10/01/2017 13:04:14

indecisionMaybe they have been watching the physics programs they put out at times and some have covered Schrodinger. Bound to have just been on the cat though so they must have read or heard more.

John

-

Cat in a sealed box: it died of suffocation first anyway! Similar results without the experiment.

Edited By V8Eng on 11/01/2017 22:02:23

Michael Gilligan11/01/2017 23:47:18
9055 forum posts
395 photos

Posted by Jon Gibbs on 10/01/2017 11:40:52:

Yes but the most splendid irony IMHO is that the inch is now defined in terms of the metre

.

Now contemplate that the metre is ultimately defined in terms of time. **LINK**

http://www.bipm.org/en/publications/si-brochure/metre.html

So where does that put that most sacred of all units [the speed of light] question

... Think about it ...

MichaelG.

.

P.S. ... I tried raising that one a while back, to no avail.

Maurice12/01/2017 00:01:22
220 forum posts
39 photos

V8Eng's reference to the term" almost exactly" being used on TV, brings to mind the number of times that TV presenters find things that are "nearly unique"!

Maurice

Michael Gilligan12/01/2017 00:21:14
9055 forum posts
395 photos
Posted by Maurice on 12/01/2017 00:01:22:

... things that are "nearly unique"

.

or [even worse] "very unique"

MichaelG.

John Alexander Stewart12/01/2017 03:24:00
607 forum posts
49 photos
So where does that put that most sacred of all units [the speed of light] question

I think the thoughts that the potential of a varying fine structure constant maybe has put paid to the thought of a speed of light constant. Then again, maybe not. I'm not sure in my own mind about what a non-constant constant that quantum mechanics/ quantum physics is built upon really means.

Sigh. JohnS.

Mike12/01/2017 09:13:28
avatar
406 forum posts
2 photos

When I trained as a journalist in the 1960s I was told to treat the word "unique" the same as "dead" or "pregnant". Something or somebody either is or is not.

SillyOldDuffer12/01/2017 09:59:45
991 forum posts
202 photos
Posted by Michael Gilligan on 12/01/2017 00:21:14:
Posted by Maurice on 12/01/2017 00:01:22:

... things that are "nearly unique"

.

or [even worse] "very unique"

MichaelG.

What is and isn't proper usage in English makes my head hurt.

Unique isn't unique. For example, the rather limited Compact Oxford English Dictionary for Students gives the word 3 meanings:

  1. being the only one of its kind; unlike anything else.
  2. belonging or connected to one particular person, group or place
  3. very special or unusual

Better Dictionaries give more meanings, including the possibility of using unique as a noun as in 'The unique is also the improbable.'

Each individual snowflake is unique but there are billions of them, more or less without value. In that context it doesn't seem unreasonable to me to describe the Sergio Diamond as being 'very unique'.

Likewise, despite being a chap not full of baby, I can finish this post off with a pregnant pause...

Dave

Ajohnw12/01/2017 10:03:05
3641 forum posts
160 photos

devilWhen ever comments on things like almost crop up what always springs to my mind is these and others

In linguistics, an adjective (abbreviated adj) is a describing word, the main syntactic role of which is to qualify a noun or noun phrase, giving more information about the object signified. Adjectives are one of the English parts of speech, although historically they were classed together with the nouns.

adverb
ˈadvəːb/
noun
GRAMMAR
  1. a word or phrase that modifies the meaning of an adjective, verb, or other adverb, expressing manner, place, time, or degree (e.g. gently, here, now, very . Some adverbs, for example sentence adverbs, can also be used to modify whole sentences.

That just leaves the matter of degree. Generally it signifies very little of it. What ever it is. So in real terms what's wrong with that.

Worse still in some quarters terms like begs the question just shouldn't be used. Really there is nothing intrinsically wrong with the phrase. That one causes problems due to this sort of thing

**LINK**

but clearly it generally isn't used in that fashion so can be contextually correct.

John

-

Michael Gilligan12/01/2017 10:28:46
9055 forum posts
395 photos
Posted by SillyOldDuffer on 12/01/2017 09:59:45:

Unique isn't unique. For example, the rather limited Compact Oxford English Dictionary for Students gives the word 3 meanings:

  1. being the only one of its kind; unlike anything else.
  2. belonging or connected to one particular person, group or place
  3. very special or unusual

Better Dictionaries give more meanings, including the possibility of using unique as a noun as in 'The unique is also the improbable.'

.

Thereby demonstrating [what some would consider] the evolution of the language.

... or its degeneration ?

MichaelG.

.

http://www.etymonline.com/index.php?term=unique

Edited By Michael Gilligan on 12/01/2017 10:31:00

richardandtracy12/01/2017 11:31:21
avatar
344 forum posts
3 photos
Posted by V8Eng on 11/01/2017 22:00:04:
Posted by Ajohnw on 10/01/2017 14:08:26:

indecisionMaybe they have been watching the physics programs they put out at times and some have covered Schrodinger. Bound to have just been on the cat though so they must have read or heard more.

John

-

Cat in a sealed box: it died of suffocation first anyway! Similar results without the experiment.

Edited By V8Eng on 11/01/2017 22:02:23

This experiment always ignores the third state of cat: It could be 1) alive, 2) dead or 3) simply so furious the other two states are completely irrelevant. Yeah, we do have 4, and they demonstrate state 3 on a daily basis.

Regards,

Richard

Jon Gibbs12/01/2017 11:55:06
449 forum posts
Posted by Michael Gilligan on 11/01/2017 23:47:18:

Posted by Jon Gibbs on 10/01/2017 11:40:52:

Yes but the most splendid irony IMHO is that the inch is now defined in terms of the metre

Now contemplate that the metre is ultimately defined in terms of time. **LINK**

http://www.bipm.org/en/publications/si-brochure/metre.html

So where does that put that most sacred of all units [the speed of light] question

... Think about it ...

MichaelG.

I think I'm missing your insight here. I have tried to think about it - honest embarrassed

Is it that all measures of length are somehow shaky? - I know that the most recent definitions of the metre say that it's only valid to consider measurements in metres over distances where relativistic effects are negligible.

...or perhaps that the second is essentially a non-decimalized archane division of a year/day/hour which could be claimed as "imperial"? 

Jon

Edited By Jon Gibbs on 12/01/2017 11:59:56

Michael-w12/01/2017 12:07:13
avatar
1326 forum posts
27 photos

I hate that Schrodinger's cat idea, it's just stupid,

Michael W

 

Edited By Michael-w on 12/01/2017 12:12:09

Simon Williams 312/01/2017 12:36:24
121 forum posts
38 photos

What Schrodinger failed to take into account is that cats can walk through walls. Cat owners (now there's an oxy-moron) have known this since pre-history, and Douglas Adams documented it.

Simon

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