A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
|
From: mpalenik on 18 Feb 2010 05:08 On Feb 17, 2:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 17 Feb, 18:04, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > > On Feb 17, 12:51 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > On 17 Feb, 16:07, mpalenik <markpale...(a)gmail.com> wrote: > > > > > On Feb 17, 10:04 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > As we discussed earlier, it may be that we are only AWARE of four > > > > > > dimensions. It may well be that there are more. Then the way to > > > > > > entertain this notion is to ask the question, how would something that > > > > > > is only AWARE of two dimensions become convinced that there is a third > > > > > > dimension? This turns out to be very answerable. > > > > > > I'm afraid that was not my conclusion. As I've said, these > > > > > possibilities only seem credible to those who already hold them to be > > > > > credible. > > > > > Well, how could they seem credible to people who don't hold them > > > > credible? > > > > I fear the answer follows naturally from the question: they don't seem > > > credible, to people who don't hold them to be credible. > > > That is true by definition > > I know, which makes one wonder why you asked the question in the first > place. I was trying to find out why you even made the statement in the first place. You might as well have said "the only people who are tall are the ones who aren't short."
From: Ste on 18 Feb 2010 09:03 On 17 Feb, 21:47, PD <thedraperfam...(a)gmail.com> wrote: > On Feb 17, 2:38 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > Document that, please. The definition I gave of both those terms is > > > the one that is generally accepted in the physics profession. Do you > > > have evidence otherwise? > > > Yes, you provided the evidence yourself with "string theory", > > I believe I conveyed to you that, speaking to each other, physicists > usually do not call "string theory" a theory, for precisely the reason > that it fails to meet the criteria of a theory. However, physicists do > use the term "string theory" in colloquial language for the sake of > readers of popularizations and general public periodicals and TV > shows. This is an attempt to make the subject accessible to that > audience, though at the expense of accuracy, exactly as I alluded to > earlier. I simply disagree. Physicists *do* call "string theory" a theory. > > and > > indeed you don't commit yourself any stronger than talking of the > > "generally accepted definition". And yet, as I say, this convention is > > regularly flouted, and it just becomes ludicrous to justify it in > > terms of "well they are a minority", "that was a popularisation", etc. > > On the contrary, I just got through explaining to you that scientists > DO use conventional language in popularizations, with full risk that > it may introduce verbal ambiguity and lead to misconceptions, because > the aim of popularization is not to teach but to inspire readers to > read more carefully prepared materials suitable for teaching. Rubbish. Words mean what people understand them to mean - the idea that physicists "speak a different language at work", or go into some sort of mode of "serious discussion" where they use only the special meanings, is just ludicrous. The word "theory" has no consistent special definition amongst the scientific community, and I'm simply not willing to accept your contentions otherwise. At best, I'm willing to accept that *you* attribute a specialised meaning to the word, but that reinforces my view that too many people here spend too long arguing about words, which are in fact being used correctly within their accepted definitions and context, instead of getting on with a substantive argument. > > As for "material", as I say, if you're discussing anything > > philosophical then it alludes to "materialism", > > Philosophy is not physics. It is when we're talking about the nature of the real world, which is exactly the context in which these words cropped up. > > Broadly I agree that words should be used within their correct > > definitions, and this is one situation where a correction would be in > > order. > > > But there is no argument that words, like "theory", should be given an > > unwarranted narrower definition than their legitimate everyday > > meaning, simply because one is talking to a specialist - unless, of > > course, it is expressly stipulated that the narrower definition will > > be used for the time being for the sake of necessary accuracy. > > I disagree. In a teaching environment, that is EXACTLY the stipulation > that is made, over and over again as the terms come up in the course > of study. "Momentum", "velocity", "energy", "heat", "field", > "potential", "mass" are all examples of terms that are very carefully > segregated from conventional usage in the context of physics. But the point is that, within physics, words like velocity *are* used very consistently in their specialised meaning, and they have a very rigorous definition. "Theory" is completely the opposite - it is consistently used as loosely as the everyday meaning even amongst professionals, and it's alleged specialised meaning is very ill- defined.
From: JT on 18 Feb 2010 09:32 On 18 Feb, 11:08, mpalenik <markpale...(a)gmail.com> wrote: > On Feb 17, 2:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 17 Feb, 18:04, mpalenik <markpale...(a)gmail.com> wrote: > > > > On Feb 17, 12:51 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > On 17 Feb, 16:07, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > On Feb 17, 10:04 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > As we discussed earlier, it may be that we are only AWARE of four > > > > > > > dimensions. It may well be that there are more. Then the way to > > > > > > > entertain this notion is to ask the question, how would something that > > > > > > > is only AWARE of two dimensions become convinced that there is a third > > > > > > > dimension? This turns out to be very answerable. > > > > > > > I'm afraid that was not my conclusion. As I've said, these > > > > > > possibilities only seem credible to those who already hold them to be > > > > > > credible. > > > > > > Well, how could they seem credible to people who don't hold them > > > > > credible? > > > > > I fear the answer follows naturally from the question: they don't seem > > > > credible, to people who don't hold them to be credible. > > > > That is true by definition > > > I know, which makes one wonder why you asked the question in the first > > place. > > I was trying to find out why you even made the statement in the first > place. You might as well have said "the only people who are tall are > the ones who aren't short."- Dölj citerad text - > > - Visa citerad text - At least he do not use tall meters and short meters like you. Length units can not be shorter and longer. Just as their can be no mutual timedilation time units can not be shorter and longer because of their state of motion, the units remain the same although there can be effects on the measuring equipment. JT JT
From: Ste on 18 Feb 2010 09:43 On 18 Feb, 10:08, mpalenik <markpale...(a)gmail.com> wrote: > On Feb 17, 2:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 17 Feb, 18:04, mpalenik <markpale...(a)gmail.com> wrote: > > > > On Feb 17, 12:51 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > On 17 Feb, 16:07, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > On Feb 17, 10:04 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > As we discussed earlier, it may be that we are only AWARE of four > > > > > > > dimensions. It may well be that there are more. Then the way to > > > > > > > entertain this notion is to ask the question, how would something that > > > > > > > is only AWARE of two dimensions become convinced that there is a third > > > > > > > dimension? This turns out to be very answerable. > > > > > > > I'm afraid that was not my conclusion. As I've said, these > > > > > > possibilities only seem credible to those who already hold them to be > > > > > > credible. > > > > > > Well, how could they seem credible to people who don't hold them > > > > > credible? > > > > > I fear the answer follows naturally from the question: they don't seem > > > > credible, to people who don't hold them to be credible. > > > > That is true by definition > > > I know, which makes one wonder why you asked the question in the first > > place. > > I was trying to find out why you even made the statement in the first > place. You might as well have said "the only people who are tall are > the ones who aren't short." I'm confused Mark. My position is that someone must hold a priori that alternate dimensions are a real possibility, in order to hold that any theory that employs alternate dimensions is credible. Some here do hold that alternate dimensions are a real possibility, so of course they hold theories that employ them as credible. I don't hold that alternate dimensions are a real possibility, so of course I don't accept that theories that employ them are credible. You asked "how could they seem credible to people who don't hold them credible", and my answer is that, indeed, they simply *don't* (and never will)seem credible to people who don't already hold that alternate dimensions are a real possibility. If what you're really asking is "how can people who hold alternate dimension theories to be incredible, be convinced that they are credible", the answer is "only with unequivocal and overwhelming observational evidence".
From: PD on 18 Feb 2010 09:47
On Feb 18, 8:03 am, Ste <ste_ro...(a)hotmail.com> wrote: > On 17 Feb, 21:47, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 17, 2:38 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > Document that, please. The definition I gave of both those terms is > > > > the one that is generally accepted in the physics profession. Do you > > > > have evidence otherwise? > > > > Yes, you provided the evidence yourself with "string theory", > > > I believe I conveyed to you that, speaking to each other, physicists > > usually do not call "string theory" a theory, for precisely the reason > > that it fails to meet the criteria of a theory. However, physicists do > > use the term "string theory" in colloquial language for the sake of > > readers of popularizations and general public periodicals and TV > > shows. This is an attempt to make the subject accessible to that > > audience, though at the expense of accuracy, exactly as I alluded to > > earlier. > > I simply disagree. Physicists *do* call "string theory" a theory. Not to each other, generally. To laypeople, sure, because they're using the *conventional* and loose meaning of that word, which I believe is what you were *asking* physicists to do, and as a result there is confusion about the term, which is exactly what you buy into when conventional language is used. > > > > and > > > indeed you don't commit yourself any stronger than talking of the > > > "generally accepted definition". And yet, as I say, this convention is > > > regularly flouted, and it just becomes ludicrous to justify it in > > > terms of "well they are a minority", "that was a popularisation", etc.. > > > On the contrary, I just got through explaining to you that scientists > > DO use conventional language in popularizations, with full risk that > > it may introduce verbal ambiguity and lead to misconceptions, because > > the aim of popularization is not to teach but to inspire readers to > > read more carefully prepared materials suitable for teaching. > > Rubbish. Words mean what people understand them to mean Not entirely. Words mean what people INTEND them to mean, as well. When there is synchronization between what people understand them to mean and what people intend them to mean, then there is solid communication. And when there is not, it is not. Solid communication is absolutely essential in the teaching environment, and so in that environment, great care is spent on that synchronization. "In this course, this is what we will mean by this word." In an open discussion forum like this, not so much. > - the idea > that physicists "speak a different language at work", or go into some > sort of mode of "serious discussion" where they use only the special > meanings, is just ludicrous. I'm sorry, but it's true. There is a distinct difference in the language used in professional literature intended for intra-field communication and the the language used in popularizations. > The word "theory" has no consistent > special definition amongst the scientific community, and I'm simply > not willing to accept your contentions otherwise. That's of course your choice. But that's a choice to be wrong. It's not a matter of opinion. > At best, I'm willing > to accept that *you* attribute a specialised meaning to the word, but > that reinforces my view that too many people here spend too long > arguing about words, which are in fact being used correctly within > their accepted definitions and context, instead of getting on with a > substantive argument. You can see how bogged down substantive arguments get when there isn't a clear mutual understanding about the meaning of words. > > > > As for "material", as I say, if you're discussing anything > > > philosophical then it alludes to "materialism", > > > Philosophy is not physics. > > It is when we're talking about the nature of the real world, which is > exactly the context in which these words cropped up. No, sir, they are NOT the same when we're talking about the nature of the real world. Science as a study of the nature of the real world is markedly different than philosophy, in methodology, in the confidence in truth value it associates with statements made, and in other respects as well. I have a degree both in philosophy and in physics, and I'm keenly aware of the differences between the two. > > > > Broadly I agree that words should be used within their correct > > > definitions, and this is one situation where a correction would be in > > > order. > > > > But there is no argument that words, like "theory", should be given an > > > unwarranted narrower definition than their legitimate everyday > > > meaning, simply because one is talking to a specialist - unless, of > > > course, it is expressly stipulated that the narrower definition will > > > be used for the time being for the sake of necessary accuracy. > > > I disagree. In a teaching environment, that is EXACTLY the stipulation > > that is made, over and over again as the terms come up in the course > > of study. "Momentum", "velocity", "energy", "heat", "field", > > "potential", "mass" are all examples of terms that are very carefully > > segregated from conventional usage in the context of physics. > > But the point is that, within physics, words like velocity *are* used > very consistently in their specialised meaning, and they have a very > rigorous definition. Yes, although that definition is not understood by the "ordinary man", who would readily make the mistake of thinking that something that is going at a constant 20 mph has a constant velocity. Hence a mismatch. > "Theory" is completely the opposite - it is > consistently used as loosely as the everyday meaning even amongst > professionals, and it's alleged specialised meaning is very ill- > defined. I disagree. You may not be familiar with the definition, or you may choose to believe that if the definition exists, it is not used in connotation. |