A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Ste on 26 Feb 2010 19:54 On 26 Feb, 17:34, PD <thedraperfam...(a)gmail.com> wrote: > On Feb 25, 9:05 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > I also doubt one exists at the moment, but I see that as a problem. > > It's utterly irreconcilable, within any conceptual framework that I > > know of, to have situations where, for example, a large ladder can end > > up in a smaller barn according to an observer stationary in the barn, > > but not according to an observer riding the ladder. > > Why? And here we can systematically trace back to the assumptions you > are making and then question them. In this case, you have a firm > belief that length is definable in such a way that it is intrinsic to > the object and frame-independent, and that physical "fitting" is a > function of the *intrinsic* lengths of two objects (or an object and a > container). My only contention is that it is *not realistic* to say that from the barn frame frame the ladder contracts and fits inside, while saying that from the ladder frame it is the barn that contracts and the doors actually never shut simultaneously. It is simply not realistic. If such a thing appears to happen, then it is obviously an artefact of subjective observation. > > > Your disbelief of SR stems from the fact that you don't understand it. > > > My disbelief, really, stems from the blatant lack of conceptual > > understanding of the theory. I mean, as I repeatedly point out, I > > don't know a single equation of relativity, and yet I can root out the > > conceptual contradictions immediately when people here have a crack at > > making meaningful qualitative statements in SR. The classic example, > > of course, was Paul's contention that "what is simultaneous in one > > frame can never be simultaneous in another", which of course isn't > > true according to SR. > > I'm sorry? It is very much true in SR that two spatially separated > events that are simultaneous in one frame are not simultaneous in > another frame moving relative to the first. But I contradicted that when I pointed out that two observers can be moving relative to each other, and yet undoubtedly events can be simultaneous for both. I seem to remember you conceded that point when I gave you a situation where it was true.
From: Ste on 26 Feb 2010 19:59 On 26 Feb, 17:46, PD <thedraperfam...(a)gmail.com> wrote: > On Feb 25, 9:42 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 25 Feb, 17:15, mpalenik <markpale...(a)gmail.com> wrote: > > > > On Feb 24, 10:22 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > I'm afraid I don't accept that this captures the certainty that many > > > > people have in various scientific theories. I've just responded to > > > > Mark who said that a theory with a 95% confidence should be accepted > > > > universally by all > > > > I said I'm done with this conversation, but I'm not going to let you > > > misquote me, you pathetic idiot. > > > > I said "it should be accepted by all as HAVING A 95% CHANCE OF BEING > > > TRUE". I did not say it should be accepted as being true. I said it > > > should be accepted that THERE IS A 95% CHANCE THAT IT IS TRUE BY > > > EVERYONE. THERE IS A DIFFERENCE. I REPEAT, I DID NOT SAY IT SHOULD > > > BE ACCEPTED AS TRUE--IT SHOULD ONLY BE ACCEPTED THAT THERE IS A 95% > > > CHANCE THAT IT IS TRUE. > > > > If you are so mentally degenerate that you can't understand the > > > difference, then it makes me wonder how you can make it through your > > > every day life, you moronic imbicile. > > > > Once again, I will not discuss anything with you, but I sure as hell > > > am going to call you on it if you make retarded inferences about > > > things that I've said and then try to pass that off as my viewpoint. > > > Calm down. I see that perhaps I did explicitly misquote you, although > > I'm not sure the inferences were so wrong. > > > If people accept that a particular theory has a 95% confidence, then > > what are you saying they should do as a result? Do you think they > > should devote just 95% of their time to that theory? 100% of their > > time? Some other percentage? > > > And aside from what you think they should do, what do you think they > > *actually* do? > > There's a variety of things one can do (and are done). > 1) Explore other candidates, though at a level that is commensurate > with risk-benefit analysis of the effort involved. > 2) Continue to do other tests of this model vs other models to see > where the 5% might lead (to either opening it up to 40% or closing it > to 98%, say) > 3) Let the community by itself determine organically which volunteers > from the community will plumb the 5% doubt. > 4) Design a bunch of devices that are based on a 95% assurance that > the principles of that model are correct, again weighing risk vs > benefit on the chance this is a mistake. That's fair enough in abstract. But the question is still who pursues which avenue, and what subjective perception they have of the likelihood of a particular theory being correct. After all, it's alight for scientists to pay lip service to doubt when questioned strenuously. But what of their day-to-day conduct? And what are their views of scientists who explore other avenues than themselves?
From: Ste on 26 Feb 2010 20:00 On 26 Feb, 18:20, PD <thedraperfam...(a)gmail.com> wrote: > On Feb 26, 1:31 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > In what sense can it be said to work if it doesn't predict what is observed. > > > It does predict what is observed, but only in a very loose way, > > No. It *accommodates*, it does not *predict*. And this is where there > is a difference. > It is one thing to say that a certain behavior is *conceivable* within > a mental picture, it is another thing entirely to say that it is > *demanded* from a model. A prediction is usually precise enough where > it will be able to say, "you will see behavior X in quantity Qx, > behavior Y in quantity Qy, and behavior Z in quantity Qz, but you will > NEVER see behavior W and you will not see behavior Z in any other > quantity." This your mental picture does not do. But it does for example. My mental picture says that gravity will never become stronger with increasing distance. That is a firm prediction.
From: Paul Stowe on 26 Feb 2010 20:06 On Feb 26, 5:00 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 26 Feb, 18:20, PD <thedraperfam...(a)gmail.com> wrote: > > > On Feb 26, 1:31 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > In what sense can it be said to work if it doesn't predict what is observed. > > > > It does predict what is observed, but only in a very loose way, > > > No. It *accommodates*, it does not *predict*. And this is where there > > is a difference. > > It is one thing to say that a certain behavior is *conceivable* within > > a mental picture, it is another thing entirely to say that it is > > *demanded* from a model. A prediction is usually precise enough where > > it will be able to say, "you will see behavior X in quantity Qx, > > behavior Y in quantity Qy, and behavior Z in quantity Qz, but you will > > NEVER see behavior W and you will not see behavior Z in any other > > quantity." This your mental picture does not do. > > But it does for example. My mental picture says that gravity will > never become stronger with increasing distance. That is a firm > prediction. But, in both the center of a spiral galaxy and the center of mass the gravitational potential is zero, increasing in strength until one reaches either the surface of a solid planet or, in the case of a galaxy the rotation speed verses area density starts to drop off. So, while I understand where you are coming from, technically, you're wrong. Paul Stowe
From: Ste on 26 Feb 2010 20:15
On 26 Feb, 18:14, PD <thedraperfam...(a)gmail.com> wrote: > On Feb 25, 10:47 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > You have then questioned why you should adopt the scientific metric > for "working". And the answer is, you don't have to. It's just that > when you decline, you're no longer doing science. But this lends credibility to my assertion in the first place, which is that science is a religion. > > Indeed, you have utterly failed to point out any contradiction yet, > > all you have done is constrain the behaviour of gravity tighter than > > what is otherwise possible in the conceptual understanding that I > > have, and as such amounts to "added detail" and leads to further > > accuracy, rather than requiring a fundamental conceptual overhaul. > > I *have* pointed out the contradiction. Gravity that falls off > linearly with distance is incompatible with elliptical orbits. What is > true is that I have not demonstrated this enough to you that your are > convinced that it is a contradiction. That is different. That is a > *teaching* task. I don't know that I owe it to you to *convince* you > of anything, though I may be inclined to point to a fact or two that > might spur YOUR OWN investigation into why that statement is true. I'm afraid I don't accept this Paul. It's not a contradiction, because my model didn't make any firm statement in the first place as to the quantity of fall-off. The claim it made was that gravity does fall off with distance, and you have not contradicted this - in fact, you have spectacularly supported this claim. > And the cosmos is made of earth, air, fire, and water, which certainly > seems to be true, but is hardly useful. Even though it may make > perfect and plain sense to somebody as a mental picture of the cosmos. It may have been useful at the time, as a basic analysis and a springboard for further investigation. The fact that it is not useful in retrospect is a function of the degree to which science has advanced since then. > > > And that's a case of constraining the observation to ONE experiment. > > > The two models of the nature of the coin would have other > > > implications, OTHER THAN just continuing the coin-toss experiment, > > > that would lead to a clearer experimental distinction. The coin-toss > > > experiment is experiment E1 that does not clearly distinguish between > > > models B and C. So? Now you have to find the place where they make > > > clearly distinguishable predictions, and design an experiment E2 that > > > will make that discrimination. > > > Sometimes that's just not possible. Particularly if the only way the > > coin can be tested is by tossing. > > I'm sorry, but it's the object of science to FIND the other ways to > test a claim. But you've got to accept that sometimes there may be no other realistic way of testing. There's no point just saying "well science must find a way", because in some cases either theory or material circumstances may simply rule out any other kind of test. > That is how the progress is made. I simply refuse to > submit to your hypothetical situation where you say, "How does science > discern between two theories when the only information it has > available doesn't discern between the two theories?" It DOESN'T. It > goes and finds the information that DOES discern the two. As above. > > > > One example is the lip-service paid to doubt and uncertainty, whereas > > > > I can give you Mark who holds that a theory with 95% confidence should > > > > not just be accepted by most people, but all people. > > > > I don't hold the same conviction about this that he does. People > > > CHOOSE what they believe and they CHOOSE the methods by which they > > > become convinced of what they should believe. If you CHOOSE NOT to > > > adopt the scientific method, that's your prerogative, but it just > > > marks what you DO choose to do instead as something other than > > > science. Poetry perhaps. > > > There are many interesting answers in asking what causes a choice. But > > besides that, I think your definition of the scientific method is > > completely wrong. As Kuhn puts it (I was just flicking through the > > book again), the scientific method has only "pedagogic utility" and > > "abstract plausibility". > > And now you presume that Kuhn's position is either authoritative, or > that scientists would endorse it. No, I'm simply having to draw on authority to rebut your just-so statements about the views of physicists collectively, which indeed is the very argument you invoke again, by implicitly saying "ah, well physicists reject Kuhn's view of science...". |