A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: mpalenik on 24 Feb 2010 22:09 On Feb 24, 9:32 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 24 Feb, 08:30, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > > On Feb 24, 2:15 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > That's not true. A further 100 tosses would not discern definitively > > > > > between the two theories, for the outcome would still be technically > > > > > consistent with either theory. > > > > > In fact, though, you can calculate the probability that either > > > > hypothesis is correct if the coin toss comes out a certain way after > > > > 100 tosses. 100% heads, for example, would put you well past a 95% > > > > confidence interval. And in fact, when experimentalists publish their > > > > data, they do also publish such confidence intervals. > > > > But even a weighted coin would be unlikely to give 100% heads. In any > > > event, the point is that there is still no definitive test, and unlike > > > a simple coin-toss outcome theory, the truth of real-world scientific > > > theories and experiments are not nearly as easily reducible to this > > > kind mathematical probability. > > > I don't think you understand how statistics works. We can say "a > > weighted coin should come up heads > 50% of the time." We can say > > "given that we threw the coin n times and got x number of heads, what > > is the probability that this is a fair coin." We can then compare the > > null hypothesis (that it is a fair coin) to the "heads comes up more" > > hypothesis. > > I think you're probably arguing this at a different level. I > understand the statistics of this scenario perfectly. > > > > And indeed, if the confidence level is 95%, then that doesn't mean > > > 100% of people should hold the weighing-theory to be true (i.e. on the > > > basis that the most likely explanation is likely to be the correct > > > one). On the contrary, it would be desirable to have, say, only 95% of > > > people working within the assumption that the weighting-theory is > > > true, and the rest working with the assumption that it is not true. > > > First of all, after 100 flips you'd be well above 95%--probably well > > above 99%. > > Whatever the probability is, it doesn't matter, except that it is not > 100%. > > > But regardless, a 95% confidence interval doesn't mean > > that 5% of all people should believe that the coin isn't weighted. It > > means that everybody should believe that there is a 95% chance that > > the coin is weighted. There's a big difference. > > Ever heard of "putting all your eggs in one basket"? > Ever heard of "95% is not 100%"? You still don't seem to understand how this works. Read what I wrote again. > > > > > > > > > > Notice how different this approach is from sitting back and trying to > > > > > > decide whether mathematicians (or gangsters) are groups of people who > > > > > > self-select themselves into delusions, and therefore their models are > > > > > > not to be trusted. Why do that kind of nonsense, when you can simply > > > > > > ask the coin to show its colors? > > > > > > Because in the real world it is not simply a case of flipping the coin > > > > > an infinite number of times. Let's face it, we both submit to evidence > > > > > - that cannot be the difference between us. > > > > > Actually, you tend to hand-wave away any evidence you don't like as > > > > 100 years of bad experiments, as in the case of the Michaelson Morely > > > > experiment and others like it with similar, albiet more refined, > > > > steups, which you were insisting had problems for a long time. > > > > Perhaps the difference is, we understand the experimental evidence and > > > > you don't. > > > > I haven'thand-wavedthe evidence away at all. If you mean that I've > > > just dismissed evidence out of hand (presumably because you think I > > > find it undesirable), then I would challenge you to identify where I > > > have done this. If you mean something else, then I would ask you to > > > clarify what you mean when you say I've "hand-wavedevidence away". > > > Ok, let's look at your whole thread about measuring the speed of > > light. > > > You came up with a bunch of hypotheses that have no basis in physical > > reality--about how brightness could affect the location of > > interference fringes (it doesn't, and I proved it doesn't), about the > > speed of light and measured brightness being able to "compensate" for > > each other--again none of which have any basis in physical reality-- > > all because you wanted to dismiss the Michaelson-Morley type > > experiments. Again, there was nothing sensible about any of it, > > except that it was a way for you to attempt to justify not having to > > believe the speed of light isotropy measurements. > > And indeed, I said openly that I couldn't make that work, once I'd > been able to construct a graphic where I could see the proof with my > own eyes, and clearly the physical understanding on which that was > based is untenable. As it stands, I don't really have any workable > physical model for light under relativity. And if this were actually coming from someone attempting to practice legitimate science or propose a realistic theory, he would have done that work ahead of time, instead of coming here and insisting that those claims were true before making any attempt to back them up and dismissing everyone's attempts to explain the experiments. > > That said, I don't think anyone can accuse me of being insensible or > lacking integrity in the way you suggest that it was a contrivance to > avoid believing the obvious. It's not a matter of integrity, it's a matter of knowledge of the scientific method and understanding of the requirements of scientific theories. > > > > And before you jump in and say that this newsgroup is not > > > representative of physicists, let me be clear that I've read pretty > > > widely already and this utterly lack of conceptual clarity is by no > > > means confined to this newsgroup. > > > I wasn't going to say that, but what extensive interaction have you > > actually had with physicists? And reading "A Breif History of Time" > > doesn't count. > > Oh come on Mark. I first read A Brief History years ago, and just > happened to mention that I'd read it again recently. > I actually didn't even realize you said that you'd read it, it was just a guess. So what extensive interaction have you had with the physics community (again, outside that book)? > > > > > > > For example, consider this illustration: > > > > A------B---C > > > > Basically you can express the distance AB with the value x, the > > > distance BC as value x/2, and the distance AC as value 3x/2. Or you > > > can express it as AB = 2x, BC = x, and AC = 3x. But this form of > > > expression always relies on comparison, and if you change the > > > reference value of X then all the other values change numerically (but > > > not physically - there is still some essential relationship that is > > > physically invariant). > > > First of all, physically, if you double the distance between two > > objects, that does make a difference. For example, if you bring two > > molecules close engouh together, they will start repelling instead of > > attracting (this is the principle behind atomic force microscopy). If > > you shrank the sun down into a small enough region, it would become a > > black hole. > > > The invariant quantity is the ratio of lengths: 2:1. And yes, this > > can be expressed as 1:2. > > Yes, but you've subtly introduced a comparison again, of expressing > one length as a ratio of another. The question is how to express the > distance of BC in such a way that, no matter how the distance AB > changes, and without reference to any other standard, the expressed > distance of BC does not change. By your ratio method, if we double the > distance of AB (or halve the distance BC), then the ratios change to > 4:1. That's just retarded, quite frankly. You don't want to use units to measure it, and you don't want to compare it to anything else. You don't want relationships of distances, you don't want it in terms of meters, and presumably, you wouldn't accept the speed of light and time, either. Honestly, I give up at this point, I'm done with this conversation. If you don't even get why that's a stupid question, there really is no hope for you. I have much better things to do with my time. This is getting beyond idiotic.
From: Ste on 24 Feb 2010 22:22 On 24 Feb, 17:32, PD <thedraperfam...(a)gmail.com> wrote: > On Feb 24, 2:56 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > On 23 Feb, 15:57, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Feb 22, 11:16 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > And as I've > > > > said, repeatedly, what you call my "cogs and levers" approach is far > > > > more flexible than your caricature would imply. > > > > Yes, to the point where your cogs-and-levers picture permits almost > > > immediately obvious internal contradictions, as I've pointed out. > > > Indeed, but that's why I don't disparage a mathematical refinement of > > it, and I see the maths as "adding detail to the picture". > > I'm sorry, but in my mind there's a big difference between "adding > detail to the picture" and "showing that the picture is self- > contradictory". But you didn't show that it was contradictory. All you did was further constrain the relationship between gravity and distance. > The simplest example I can give you is your claim that > a cogs-and-levers view has no problem whatsoever with gravity falling > off as the distance rather than as the distance squared, while also > being fully consistent with observed comet orbits. Showing that these > two circumstances are completely incompatible is not "adding detail to > the picture". It is showing a serious shortcoming of your qualitative > approach. All you have shown is that the qualitative approach is not mathematically rigorous, but I've admitted as much. > > > > You're characterising my position as being far more hardline than it > > > > is. What I'm saying, at it's most simple, is that I'm not willing to > > > > simply take the word of "authority". Separate from that, I've also > > > > made it clear that I have certain axioms that are not in principle > > > > unquestionable or irrefutable, but which would require such an > > > > overwhelming amount of evidence to overturn that they are, in > > > > practice, probably irrefutable. > > > > Then by all means study physics the way it is intended to be studied. > > > That is, accept nothing without test. There is a reason, as I said, > > > why physics courses contain a laboratory element, so that you can see > > > how experiments can be designed to distinguish between different > > > models, and you can see with your very own eyes the results that make > > > that distinction. There is no better authority than your own eyes. > > > I'm more concerned with how experiments fail to distinguish between > > models, > > You'll have to give me some examples. I'll start. It is certainly true > that two models can be compatible with the results of a *given*, > isolated experiment. I've described this before, and I'll recap > briefly with a toy example because you found the last exposition of > this too "technical" to follow. Suppose you have three models -- A, B, > and C -- and two experiments E1 and E2. Experiment E1 may rule out B > but be compatible with both A and C. Experiment E2 may rule out A but > be compatible with both B and C. But with the pair of results from E1 > and E2, you can firmly say that C is favored over both A and B, even > though neither experiment can clearly pick out one model from the > others. Of course. I wasn't really looking to discuss this sort of simple logic with you. I was making a much broader statement about how some hypotheses can be very difficult to test definitively. I gave you the example earlier about the coin-toss scenario. > In our present state of the Standard Model, there are numerous > extensions that are permitted by the present data -- supersymmetry, > any number of string models, spin-foam quantum gravity, and so on. You forgot "spaghetti". > > and moreover I'm interested in how often the availability of > > experimental evidence, and its interpretation, is constrained by the > > theory, rather than the other way around. > > And on this point, I've repeatedly maintained that it isn't. All > you've offered in the converse is a quote by Einstein that it is. No, I've also referred you to the works of Kuhn and Lakatos. And indeed, the very method that you describe involves formulating a theory and then testing its predictions - in other words, the tests that are carried out are constrained by the predictions made by the theory. One would be unlikely to test for something that the theory does not predict in the first place. > > I dare say that, unlike you, > > I don't have actual faith in the practice of science, even though I > > don't discount its usefulness. > > Precisely. And since you do not believe in the process of science, > there is no way possible for science to convince you of the truth of > its claims. Nor is it the *task* of science to convince even those who > do not believe in the methodology. After all, you cannot teach a > lamppost algebra and it is futile gesture for algebrists to try, not > to mention a futile expectation that algebrists succeed. Indeed, but then do you concede that science amounts to a religion? It certainly ought to strike you as one. > > Yes but in reality the theory itself is not applied independently of > > human intervention. As I say, if a theory is subtly given lots of > > leeway and lots of room for interpretation, and if the opportunities > > for definitive tests are relatively limited, then it's possible that > > it will be regarded as "true" even though it is not, simply because it > > "works" either as a sufficient approximation and/or because it only > > accidentally manages to account for the real variables involved. > > And that's what we MEAN when we say a theory is accepted. 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 - that clearly doesn't seem to acknowledge not only the problem of accurately ascertaining confidence in the first place, but secondly an acknowledgement that other avenues should be explored in parallel lest the most likely theory turn out to be totally wrong (which it inevitably will at some point, if its confidence is less than 100%). Ironically, Mark's psychology revealed there actually describes what I was saying to you weeks ago, which is that only when scientists are disciplined by starvation of further progress do they seriously start to go back and reconsider avenues which were held to be less likely to bear fruit when they were first encountered. While there still seems to be further progress that can be wrung from existing avenues, then scientists (in conduct if not in words) do not seriously entertain doubt at all. They follow Mark's logic of treating the most likely explanation as the universally correct one, and probably even go as far as disparaging those who pursue alternative paths. > This is not > a flat-out statement that is TRUE beyond all alternate possibilities. > It is a statement that it is the BEST model available to us at the > moment, and is accepted provisionally until a better one comes along. > > You'll not find a physicist who is willing to claim that he KNOWS the > Standard Model is the correct description of nature. He will certainly > tell you that it is the best model (in the sense that it is > demonstrated to work in the way described above) to date. He will also > likely tell you that it will eventually be replaced by a better model, > but that we have a poor idea of what that better model might be. There > are some promising leads, however. We'll see about that. Lol. > > > > > But it does beg the question of whether the *method* is the one to be > > > > > pursued to determine the truth. You've said you're not sure you > > > > > believe it is, but you don't have a better way of proceeding. > > > > > Because like I say Paul, I'm not here to sell anything. After hours of > > > > chiselling, conservatives always fall back on the question "is there > > > > any better way?", and of course the very method you're espousing may > > > > well be better if only its proponents actually acknowledged it's > > > > systematic deficits and failings. > > > > I'm not claiming the process is perfect. Neither is Christianity, free- > > > market capitalism, democracy, or justice by jury of peers, in any of > > > the forms those are practiced. But what is true is that diligence and > > > faithfulness to the principles of each of those do tend to remove or > > > correct excursions over a period of time. > > > Well sticking to the subject of the scientific method, you're probably > > right that over a period of time abiding by its principles probably > > keeps the whole thing on track. > > Right. > > > The problem is of keeping scientists > > in conformity with their principles - particularly where they've > > developed elaborate belief systems that allow them to think that they > > are in conformity while not being in conformity at all or where the > > principles come to be interpreted in a way that they lose all value. > > I don't know what principles of investigation have come to be > interpreted in a way that they have lost all value. 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. > Note again, I'm talking about the principles *of investigation* and > not axioms about nature itself. Science DOESN'T HAVE mandatory axioms > about nature itself, though it does have assumed principles about how > to investigate nature. I think it's probably very difficult to extricate axioms concerned with nature from axioms concerned with the investigation of nature. I think you might find any attempt to do so renders the resulting statement trite and meaningless.
From: Peter Webb on 25 Feb 2010 02:19 "mpc755" <mpc755(a)gmail.com> wrote in message news:f65fe091-2c6e-4a1d-9c50-21872decd4c7(a)t42g2000vbt.googlegroups.com... On Feb 24, 3:48 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > > > How do you work out your speed "relative to the ether"? What makes > > > > you > > > > think > > > > it exists at all? > > > > What you can determine is your state, or approximate state, with > > > respect to the aether. > > > > _________________________________ > > > How, exactly? How can you work out your speed relative to the ether? > > > The speed of one reference frame with respect to the aether can be > > determined relative to another reference frame. > > > ______________________ > > How? > > > Atomic clocks 'tick' based on the aether pressure in which it exists. > > An objects momentum determines the aether pressure on and through the > > object. The greater the momentum the greater the associated aether > > pressure. > > > The speed of a GPS satellite with respect to the aether causes it to > > displace more aether and for that aether to exert more pressure on the > > clock in the GPS satellite than the aether pressure associated with a > > clock at rest with respect to the Earth. This causes the GPS satellite > > clock to "result in a delay of about 7 s/day". > > > ________________________________ > > GPS satellites cannot be used to measure ether speed. Time dilation for > > GPS > > satellites is exactly as predicted by Relativity, which does not include > > a > > component for ether speed. So if that is your test of ether theory, it > > failed. > > Time is a concept. There is no such thing as spacetime. The rate at > which atomic clocks tick is based on the aether pressure in which they > exist. Thinking time actually changes is incorrect. > > If you dropped a clock with a paddle off of a boat and the deeper it > was dropped into the ocean the slower it 'ticked', as determined by a > clock on the boat, would you say time has changed or would you say the > increase in hydrostatic pressure is causing the clock to 'tick' > slower? > > > Can you describe a single experiment which you believe would show a > > different result from SR if your theory was correct? > > ______________________________ > Short answer, no, you cannot name a single experiment where your theory is > different to SR. You therefore believe that an 80 foot ladder can fit > inside > a 40 foot barn, and the twins "paradox". Welcome to reality. If the ladder is less at rest with respect to the aether and the barn is more at rest with respect to the aether, the ladder, if it is traveling at close to 'c' and length contraction is physical, will fit in the barn. If the barn is less at rest with respect to the aether and the ladder is more at rest with respect to the aether, the ladder, if it is traveling at close to 'c' and length contraction is physical, will not fit in the barn. Motion is not relative between frames of reference. Motion is with respect to the aether. If the spaceship is moving fast enough, the twin and the atomic clock on the spaceship, will exist under more aether pressure than the twin on the Earth. The atomic clock on the spaceship will 'tick' slower. It is unknown if the additional aether pressure on the twin will cause the twin to age less, or more. The rate at which atomic clocks 'tick' has nothing to do with time. Even though the atomic clock on the spaceship 'ticks' slower than a similar clock on the Earth and even though there is additional aether pressure on the twin in the spaceship, it is not known if the twin on the spaceship will age less, and even if the twin on the spaceship ages less, it is not because time has changed. Time does not change. Time is a concept. ________________________________ Short answer, no, you cannot name a single experiment where your theory is different to SR. You therefore believe that an 80 foot ladder can fit inside a 40 foot barn, and the twins "paradox". Welcome to reality.
From: Peter Webb on 25 Feb 2010 02:21 "mpc755" <mpc755(a)gmail.com> wrote in message news:4374851f-73ff-4aac-8425-f36bc496fb4a(a)g23g2000vbl.googlegroups.com... On Feb 24, 3:48 am, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > > > > How do you work out your speed "relative to the ether"? What makes > > > > you > > > > think > > > > it exists at all? > > > > What you can determine is your state, or approximate state, with > > > respect to the aether. > > > > _________________________________ > > > How, exactly? How can you work out your speed relative to the ether? > > > The speed of one reference frame with respect to the aether can be > > determined relative to another reference frame. > > > ______________________ > > How? > > > Atomic clocks 'tick' based on the aether pressure in which it exists. > > An objects momentum determines the aether pressure on and through the > > object. The greater the momentum the greater the associated aether > > pressure. > > > The speed of a GPS satellite with respect to the aether causes it to > > displace more aether and for that aether to exert more pressure on the > > clock in the GPS satellite than the aether pressure associated with a > > clock at rest with respect to the Earth. This causes the GPS satellite > > clock to "result in a delay of about 7 s/day". > > > ________________________________ > > GPS satellites cannot be used to measure ether speed. Time dilation for > > GPS > > satellites is exactly as predicted by Relativity, which does not include > > a > > component for ether speed. So if that is your test of ether theory, it > > failed. > > Time is a concept. There is no such thing as spacetime. The rate at > which atomic clocks tick is based on the aether pressure in which they > exist. Thinking time actually changes is incorrect. > > If you dropped a clock with a paddle off of a boat and the deeper it > was dropped into the ocean the slower it 'ticked', as determined by a > clock on the boat, would you say time has changed or would you say the > increase in hydrostatic pressure is causing the clock to 'tick' > slower? > > > Can you describe a single experiment which you believe would show a > > different result from SR if your theory was correct? > > ______________________________ > Short answer, no, you cannot name a single experiment where your theory is > different to SR. You therefore believe that an 80 foot ladder can fit > inside > a 40 foot barn, and the twins "paradox". Welcome to reality. If the ladder is less at rest with respect to the aether and the barn is more at rest with respect to the aether, the ladder, if it is traveling at close to 'c' with respect to the aether and length contraction is physical, will fit in the barn. If the barn is less at rest with respect to the aether and the ladder is more at rest with respect to the aether, the ladder, if the barn is traveling at close to 'c' with respect to the aether and length contraction is physical, will not fit in the barn. Motion is not relative between frames of reference. Motion is with respect to the aether. If the spaceship is moving fast enough, the twin and the atomic clock on the spaceship, will exist under more aether pressure than the twin on the Earth. The atomic clock on the spaceship will 'tick' slower. It is unknown if the additional aether pressure on the twin will cause the twin to age less, or more. The rate at which atomic clocks 'tick' has nothing to do with time. Even though the atomic clock on the spaceship 'ticks' slower than a similar clock on the Earth and even though there is additional aether pressure on the twin in the spaceship, it is not known if the twin on the spaceship will age less, and even if the twin on the spaceship ages less, it is not because time has changed. Time does not change. Time is a concept. ____________________________ So you make no predictions at all that are different to SR. What a waste of time.
From: Peter Webb on 25 Feb 2010 02:53
"Jerry" <Cephalobus_alienus(a)comcast.net> wrote in message news:d28e8820-699c-4501-99ca-0802936a45b2(a)k41g2000yqm.googlegroups.com... > On Feb 24, 3:13 am, "Peter Webb" > <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: >> "Jerry" <Cephalobus_alie...(a)comcast.net> wrote in message >> >>> news:0baac22d-ad06-4136-b1b2-d7144955080f(a)a18g2000yqc.googlegroups.com... >>> Should the speed of light ever be discovered not to precisely >>> equal "c" (and there is some controversial evidence that this >>> may be the case for high energy gamma rays), this will have NO >>> CONSEQUENCE WHATSOEVER in regards to the validity of relativity, >>> since the "c" which is the speed of light is not the same "c" >>> which determines the properties of spacetime. >> >> ___________________________________ >> Although I agree with most everything else you have written in your post, >> not unfortunately the above. >> >> Light does have something of a priveleged position in SR, because if the >> Universal speed limit (lets call it d) was not equal to c, then Galileo's >> principle of relativity would be damaged or broken. >> >> Specifically, we know from Maxwells eqns that a light wave viewed in a >> different reference frame has a wavelength that transforms according to >> Lorentz using 'c'. If other matter used 'd', you could determine your >> absulute speed through the ether by measuring the wavelength of light >> which >> varies by c with a metre rule which varies as d. > > For the speed of light c not to equal the universal speed limit d > would mean only that Maxwell's equations need to be replaced by > Proca's equations, which allow for the possibility of a massive > photon. > And there is the rub. You cannot use 'd' instead of 'c' in SR without breaking either Maxwell or Galilean Relativity. Using 'c' as the speed limit in SR is the only choice that doesn't break something else; its not simply based on observation or wishful thinking. > If such were the case, you could no more measure your absolute > speed through the aether using light than my imaginary beings > in the alternate universe could measure their absolute speed > against neutrinos or, for that matter, against speeding > locomotives. > > Fortunately, the speed of light c DOES seem to equal the > universal speed limit d to an accuracy of at least 10^-16. > http://www.skyandtelescope.com/news/39867717.html > > The minor discrepancy noted in the Fermi Gamma Ray Telescope > measurements could simply be a reflection of our ignorance > concerning the mechanism of gamma ray bursts, or (more exciting) > could be indicative of quantum foam effects. Even if confirmed, > these results should not be misconstrued as any sort of disproof > of SRT within its classical domain of applicability. > > Jerry > I was unaware of the finding, but am not impressed or surprised. What the article doesn't mention is that all light lags the neutrino flux, which may or may not comprise particles that have mass at various times. If shorter light wavelengths are slowed more than longer ones, it just means space has a non-zero refractive index. In practice, all known materials have non-zero refractive indexes, apparently now also including interstellar space. Its a long way from "interstellar space has a non-zero refractive index" to quantum foam. Even ignoring the fact that we don't actually know the high and low energy photons were created at the same time. Thanks for posting it though. The link at the bottom http://www.newscientist.com/article/mg20126911.300-our-world-may-be-a-giant-hologram.html?full=true was very interesting. |