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Post by mrsonde on Jul 2, 2016 16:28:52 GMT 1
I've just been listening to a very strange BBC "science" program in my shed: How Long is a Piece of String?, I think it was called. By Alan Davies, which should tell you how in-depth and reliable it was. On the other hand, he did consult a number of scientists in his quest - the usual scattering of obscure and bizarre authorities on quantum mechanics, spouting the usual mix of fantasy and metaphysical nonsense that such eccentrics are fond of doing.
As far as I'm aware, there are very conscientiously maintained standards for such measures as the IS definition of length. They can even tell how much this standard shrinks per year due to atom leakage. I can imagine no difficulty in holding a piece of string at whatever similarly defined IS measure of tension, and determining according to equally precise IS units the end points, whether according to electron orbit or size of nucleus. The limit of uncertainty due to the Heisenberg Principle is a precisely definable limit and, ultimately, comes down to a quantum of space-time. So - that's the length of a piece of string: under this much tension, it's that long: so many quanta of distance.
Isn't it?
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Post by fascinating on Jul 3, 2016 10:30:54 GMT 1
Do the atoms in the string vibrate, depending on temperature?
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Post by mrsonde on Jul 4, 2016 12:10:05 GMT 1
Yes, and various other variable constants affect your measurement, but this doesn't mean that length has no absolute meaning, which was the conclusion and, I'm fairly certain, the whole point of the program. Within these specified parameters, the string is this long, definitively. Change your specifications, and it's slightly different - but precisely so.
I think it was Euler who first pointed out, and proved, that any natural delineation - the coastline of Britain, say, or the circumference of the Earth - was, without specifying your parameters of scale, of infinite length. A matter of the fractal nature of Nature, ultimately. That doesn't mean that the advent of quantum physics means that all measurements are arbitrary, that it all totally depends on who's looking, and other such typical nonsense that so appeals to the idealist-minded mystics like Abacus.
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Post by alancalverd on Jul 4, 2016 17:36:59 GMT 1
The problem is that the unit of force depends on the fundamental units of length, time and mass. Currently we have adequately reproducible time and length standards based on the atomic clock but the standard mass remains a lump of platinum, so you can't measure the string under a fixed tension to consistent accuracy. And anyway, string tends to creep under tension.
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Post by mrsonde on Jul 4, 2016 19:18:02 GMT 1
The problem is that the unit of force depends on the fundamental units of length, time and mass. Currently we have adequately reproducible time and length standards based on the atomic clock but the standard mass remains a lump of platinum, so you can't measure the string under a fixed tension to consistent accuracy. And anyway, string tends to creep under tension. You are not claiming that a lump of platinum or anything else is not entirely determinable within specified parameters, are you? You are not claiming that "mass" is a meaningless measurement because it's ever-so-slightly variable under various conditions, are you? As for "creep" - that's not the issue, and nor is tension. Specify the time, the tension, and various other influential factors, and you have the length, which would not and could not be significantly different, whatever laboratory conducted the same experiment. It would not be meaningless because there are such alleged phenomena as the Uncertainty Principle or Black Holes.
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Post by alancalverd on Jul 7, 2016 23:26:03 GMT 1
Being a physicist who has designed and built primary measurement standards,I can't be bothered to read any paragraph that misuses "parameter".
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Post by mrsonde on Jul 20, 2016 5:49:56 GMT 1
Being a physicist who has designed and built primary measurement standards A gauge for the SI unit of BS, was it? No, do tell. You're not that guy that spends years rounding off the sphere of platinum by eye and a bit of glass paper are you? What I want to know is: who would be able to check your work? What "misuse" could that be then? I was using the term in its standard English (or scientific) sense, I don't know how it's used in Serbo-Croat: "a parameter is an element of a system that is useful, or critical, when evaluating the identity of a system; or, when evaluating the performance, status, condition, etc. of a system." Perhaps there's another meaning in the field of bsology?
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Post by fascinating on Jul 20, 2016 8:45:11 GMT 1
I've just been listening to a very strange BBC "science" program in my shed: How Long is a Piece of String?, I think it was called. By Alan Davies, which should tell you how in-depth and reliable it was. On the other hand, he did consult a number of scientists in his quest - the usual scattering of obscure and bizarre authorities on quantum mechanics, spouting the usual mix of fantasy and metaphysical nonsense that such eccentrics are fond of doing. As far as I'm aware, there are very conscientiously maintained standards for such measures as the IS definition of length. They can even tell how much this standard shrinks per year due to atom leakage. I can imagine no difficulty in holding a piece of string at whatever similarly defined IS measure of tension, and determining according to equally precise IS units the end points, whether according to electron orbit or size of nucleus. The limit of uncertainty due to the Heisenberg Principle is a precisely definable limit and, ultimately, comes down to a quantum of space-time. So - that's the length of a piece of string: under this much tension, it's that long: so many quanta of distance. Isn't it? Are you saying that you could come up with a single figure for the length of a piece of string, and declare that the quantity was absolutely true. Suppose the string is frozen to absolute zero and there is no atomic movement or atomic loss, and you can use a microscope to see the atoms, how do you define where the electrons in the very last atom of the string are?
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Post by mrsonde on Jul 20, 2016 14:23:22 GMT 1
I've just been listening to a very strange BBC "science" program in my shed: How Long is a Piece of String?, I think it was called. By Alan Davies, which should tell you how in-depth and reliable it was. On the other hand, he did consult a number of scientists in his quest - the usual scattering of obscure and bizarre authorities on quantum mechanics, spouting the usual mix of fantasy and metaphysical nonsense that such eccentrics are fond of doing. As far as I'm aware, there are very conscientiously maintained standards for such measures as the IS definition of length. They can even tell how much this standard shrinks per year due to atom leakage. I can imagine no difficulty in holding a piece of string at whatever similarly defined IS measure of tension, and determining according to equally precise IS units the end points, whether according to electron orbit or size of nucleus. The limit of uncertainty due to the Heisenberg Principle is a precisely definable limit and, ultimately, comes down to a quantum of space-time. So - that's the length of a piece of string: under this much tension, it's that long: so many quanta of distance. Isn't it? Are you saying that you could come up with a single figure for the length of a piece of string, and declare that the quantity was absolutely true. Yes. As I said above, provided you specify your parameters within specified limits there is no problem at all in coming up with a measurement that is absolutely true. It will of course be within a certain range, as specified, but that range can be infinitesimally small and precise. As with the parameter you've specified in your question - there is no difficulty in specifying the size of an electron orbit, if you're talking of its mass; nor one of its effective charge, again within your specified range (which would change pari passu, to an infinitesimal degree.) "Absolute" does not mean fixed and completely known - not always, anyway, and certainly not with measurements. But that does not mean it's meaningless - that measurements are arbitrary and not real, as this whole BBC programme, pursuing its liberal-left agenda of disseminating cognitive relativism, was intent on conveying. You can absolutely define the size of Pi, within your specified limit - a thousand decimal places, say. That doesn't mean it's not more accurate and precise to say it's 3.14 than it is 3.13.
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Post by fascinating on Jul 21, 2016 8:29:55 GMT 1
We're talking absolutes here. You have agreed that we cannot give a single value for the length of a piece of string that we know to be absolutely correct. We have to give a range. Such a range is pretty precise and useful for our purposes, but it isn't ABSOLUTELY precise.
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Post by mrsonde on Jul 22, 2016 0:10:37 GMT 1
We're talking absolutes here. You have agreed that we cannot give a single value for the length of a piece of string that we know to be absolutely correct. No, I haven't. But I do agree that you do not understand what "absolute" means. Yes? As with any absolute. Yes, it is. You just don't understand language, or for that matter mathematics and logic. You have the same problem with "race" and f'#ck knows what else. You have not been educated properly. You have not got a grasp on reality. You may even be mad, given this lack of a grasp, or very dangerously close to it.
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Post by alancalverd on Jul 22, 2016 0:15:04 GMT 1
A marginally less incorrect use of "parameter", though the context renders it meaningless. I'll encourage you with 6/10 for effort, but, to paraphrase a best-forgotten Labour politician, beware of appropriating other people's clothes lest you leave the flies undone..
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Post by mrsonde on Jul 22, 2016 0:22:30 GMT 1
A marginally less incorrect use of "parameter" I gave you the standard definition. God knows which one you're using. Whatever it is, it's certainly no more "correct". Don't, please. I'd take encouragement from someone whom I recognised as superior in knowledge or training or expertise or accomplishment. You are none of these. That much I know for certain. But in turn, with the authority of my superior knowledge, training, expertise, and accomplishment, I'll grant you a 2.
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Post by mrsonde on Jul 22, 2016 0:39:19 GMT 1
...with the authority of my superior knowledge, training, expertise, and accomplishment... But in fact you have none of these. But I do, else I wouldn't have said it. I can prove it, of course, else I wouldn't have said it. Projection, I'm afraid, dear. A sad failed comprehensive latin teacher, sacked from her profession for misconduct, desperate to impinge upon people that she might know something they don't, like perfectly proper English grammar is illegitimate because she doesn't fully understand the language that they speak.
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Post by fascinating on Jul 22, 2016 8:40:41 GMT 1
We're talking absolutes here. You have agreed that we cannot give a single value for the length of a piece of string that we know to be absolutely correct. No, I haven't. But I do agree that you do not understand what "absolute" means. Yes? As with any absolute. Yes, it is. You just don't understand language, or for that matter mathematics and logic. You have the same problem with "race" and f'#ck knows what else. You have not been educated properly. You have not got a grasp on reality. You may even be mad, given this lack of a grasp, or very dangerously close to it. What do YOU mean by the word "absolute" in this context of "absolute measurement"?
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