A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Peter Webb on 9 Mar 2010 07:16 If and when the speed of gravitation is ever measured, if the speed turns out to be identical to the speed of light, that would be an incredible finding that casts severe questions on the viability of aether theories in general. Aether theories explain wave propagation as due to the mechanical properties of the particular aether in question, and there is no reason whatsoever why two theories should share the same wave speed. Certainly the gravitational and luminiferous aethers shouldn't. Jerry ___________________________ The confirmation of the existence of the strong and weak forces and QM generally is itself a strong argument against LET at a number of levels. The argument that Lorentz put forward is based upon in the absence of gravity there are physical objects, and electromagnetism. Maxwell's eqns transformed according to the Lorentz equations. As experiments had shown that physical objects and EM transform the same way, and everybody was pretty confident about Maxwell, the obvious (and correct) answer was that physical objects must also obey a Lorentz transform. The putative mechanism was that the movement through the ether compressed physical objects. Now, that's all well and good, but how do you reconcile this with the existence of other fields, such as the strong and weak forces? It has long been known that radioactive decay rates (from say cosmic rays) and other processes that are mediated by the strong and weak force follow exactly the same transformations eg time dilation. So now this ether is doing more than compress physical objects to make them have the same transformation rules as EM, it is also compressing weak fields and strong fields in exactly the same way to force them to align with EM. By the time you have run this kludge three times (for physical objects, strong force, weak force) to align them with Maxwell, its pretty obvious that its much, much simpler to assume space itself is changing.
From: Inertial on 9 Mar 2010 08:12 "Peter Webb" <webbfamily(a)DIESPAMDIEoptusnet.com.au> wrote in message news:4b963c4b$0$1783$afc38c87(a)news.optusnet.com.au... > If and when the speed of gravitation is ever measured, if the > speed turns out to be identical to the speed of light, that > would be an incredible finding that casts severe questions on > the viability of aether theories in general. Aether theories > explain wave propagation as due to the mechanical properties > of the particular aether in question, and there is no reason > whatsoever why two theories should share the same wave speed. > Certainly the gravitational and luminiferous aethers shouldn't. > > Jerry > > ___________________________ > The confirmation of the existence of the strong and weak forces and QM > generally is itself a strong argument against LET at a number of levels. > > The argument that Lorentz put forward is based upon in the absence of > gravity there are physical objects, and electromagnetism. Maxwell's eqns > transformed according to the Lorentz equations. As experiments had shown > that physical objects and EM transform the same way, and everybody was > pretty confident about Maxwell, the obvious (and correct) answer was that > physical objects must also obey a Lorentz transform. The putative > mechanism was that the movement through the ether compressed physical > objects. > > Now, that's all well and good, but how do you reconcile this with the > existence of other fields, such as the strong and weak forces? It has long > been known that radioactive decay rates (from say cosmic rays) and other > processes that are mediated by the strong and weak force follow exactly > the same transformations eg time dilation. > > So now this ether is doing more than compress physical objects to make > them have the same transformation rules as EM, it is also compressing weak > fields and strong fields in exactly the same way to force them to align > with EM. > > By the time you have run this kludge three times (for physical objects, > strong force, weak force) to align them with Maxwell, its pretty obvious > that its much, much simpler to assume space itself is changing. Indeed it is. Even if there *is* an aether (or aethers), that it cannot be detected, and that we can model our universe without it, means it is of no use to physics.
From: Ste on 9 Mar 2010 08:26 On 8 Mar, 22:36, PD <thedraperfam...(a)gmail.com> wrote: > On Mar 8, 1:57 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 8 Mar, 19:12, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Mar 8, 8:42 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > On 4 Mar, 18:27, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Mar 4, 10:24 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 4 Mar, 15:54, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Mar 4, 1:03 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > This is what fundamentally sets apart things like creationism from > > > > > > > > > > science. Whatever other hoops creationism manages to jump through, it > > > > > > > > > > will never jump through the hoop of naturalism, and that is what > > > > > > > > > > *fundamentally* sets it apart from science. > > > > > > > > > > And also FUNDAMENTALLY distinguishes science from religion. Thanks. > > > > > > > > > Agreed, but then religion in general never claimed to be science, > > > > > > > > Agreed! And so science is not a religion in the same fashion. > > > > > > > No, but neither did one religion ever claim to be the other. > > > > > > > > > and > > > > > > > > traditional religion is almost immediately identifiable by its > > > > > > > > supernaturalism. Creationism is different in that it actually claims > > > > > > > > to be scientific in some essential respects. > > > > > > > > Ah, yes, but as has been demonstrated even to layfolk (Dover v > > > > > > > Kitsmiller), this is an unsupportable claim. > > > > > > > I agree. I'm glad you brought up that case. I just reviewed the > > > > > > judgment quickly, and apparently the court agrees that the defining > > > > > > essence of science is naturalism. > > > > > > Gee, I didn't read that into the judgment at all. > > > > > Then what did you read into it? > > > > I didn't have to read into it. Take a look at page 64 of the 139-page > > > decision: > > > ======================================================= > > > 4. Whether ID is Science > > > > After a searching review of the record and applicable caselaw, we find > > > that while ID arguments may be true, a proposition on which the Court > > > takes no position, ID is not science. We find that ID fails on three > > > different levels, any one of which is sufficient to preclude a > > > determination that ID is science. They are: (1) ID violates the > > > centuries-old ground rules of science by invoking and permitting > > > supernatural causation; (2) the argument of irreducible complexity, > > > central to ID, employs the same flawed and illogical contrived dualism > > > that doomed creation science in the 1980's; and (3) IDs negative > > > attacks on evolution have been refuted by the scientific community. As > > > we will discuss in more detail below, it is additionally important to > > > note that ID has failed to gain acceptance in the scientific > > > community, it has not generated peer-reviewed publications, nor has it > > > been the subject of testing and research. Expert testimony reveals > > > that since the scientific revolution of the 16th and 17th centuries, > > > science has been limited to the search for natural causes to explain > > > natural phenomena. (9:19-22 (Haught); 5:25-29 (Pennock); 1:62 > > > (Miller)). This revolution entailed the rejection of the appeal to > > > authority, and by extension, revelation, in favor of empirical > > > evidence. (5:28 (Pennock)). Since that time period, science has been a > > > discipline in which testability, rather than any ecclesiastical > > > authority or philosophical coherence, has been the measure of a > > > scientific ideas worth. (9:21-22 (Haught); 1:63 (Miller)). In > > > deliberately omitting theological or ultimate explanations for the > > > existence or characteristics of the natural world, science does not > > > consider issues of meaning and purpose in the world. (9:21 > > > (Haught); 1:64, 87 (Miller)). While supernatural explanations may be > > > important and have merit, they are not part of science. (3:103 > > > (Miller); 9:19-20 (Haught)). This self-imposed convention of science, > > > which limits inquiry to testable, natural explanations about the > > > natural world, is referred to by philosophers as methodological > > > naturalism and is sometimes known as the scientific method. > > > ============================================ > > > You'll note the emphasis on "testability, rather than any ... > > > philosophical coherence" which provides a scientific idea's worth. > > > Note also (emph. mine) "This self-imposed CONVENTION of science, which > > > limits inquiry to TESTABLE, natural (NOT SUPERNATURAL) explanations > > > about the natural world, is referred to by philosophers as > > > 'methodological naturalism' and is sometimes known as the scientific > > > method." > > > > Creationism (and it was also judged that Intelligent Design is thinly > > > disguised creationism) is simply not science, because it fails on the > > > metric of testability, which is an indispensable component of the > > > scientific method which in turn is indispensable to science. > > > > It seems so plainly written to me. > > > Then you are less accustomed to reading judgments than I am. It > > mentions "natural" and "naturalism" 6 times in total, and mentions the > > word "testable" only twice (and without necessarily relating > > "testability" to "falsificationism"). > > > The same is true of the whole judgment - it repeatedly refers > > contrasts the supernaturalism of creationism (or specifically ID), > > with the naturalism of science. I'm not saying one judgment of the > > court is the final word on the matter, but it was your reference and > > certainly the main emphasis is on the supernatural versus the natural, > > not specifically the untestable versus testable (or any specific brand > > of testability). > > > Come on Paul, if this reference was supposed to support your > > contention that falsificationism as opposed to naturalism defined > > science, then it wasn't fit for purpose. > > I certainly defer to you on the legal arcanery, as you should with me > in the arcanery of physics. If you say that what is written in the > judgment is tempered by how many times a word is used, and that if > there is one sentence in a judgment that uses a word once, it means > then it is not to be taken as true as statements that use a different > word more than once, I certainly will have to take your word for it. No that's not what I said. What I did say is that, on account of the frequency with which the judge (and the witnesses) connect science with naturalism (and as I say, from a cursory glance it appeared to be a connection that ran through the entire judgment), it does nothing for your position that falsificationism is what defines science. According to this judgment, a central pillar of science is naturalism. At the very least, we can agree that testability *and* naturalism define science according to the judge. However there is no extensive discussion of what "testable" means. Indeed, at times the judge and the witnesses seem to treat "testable" as being almost synonymous with naturalistic[1], and untestable as being a necessary entailment of the supernaturalistic. Indeed the one and only occasion on which "falsifiable" is mentioned (within a 140 page judgment), it is within the context of saying that ID is necessarily not falsifiable *because* is it not naturalistic. It is fair to say that, on the evidence that the court considered, the arguments were strongly focussed towards distinguishing the natural from the supernatural, not the falsifiable from the unfalsifiable. However, I'm not saying this judgment is the final word on the matter. What I am saying is that it lent your position no support as against mine. [1] Other sources have pointed out that virtually any statement about the natural world is testable (at least notionally, if not practically so). Also bear in mind that the court is not concerned with whether science rests on belief. Only in whether ID is compatible with science, which it clearly isn't.
From: Ste on 9 Mar 2010 08:37 On 9 Mar, 05:34, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > Did you look at the diagrams on the Wikipedia page on the twins paradox as I > suggested? > > This shows *exactly* what the moving and stationary clocks see as happening > at all stages of the thought experiment. This isn't the twins paradox, so it would be strange to find the answer to my question there. Also, I've read that page in the past, and I don't recall it having relevant detail. > If you didn't understand it, go through it again, and identify where you > start having problems, and I will be happy to help ... unfortunately if you > want to understand the Twins Paradox fully, you will need to do some work > yourself. We are not even talking about the twins paradox.
From: Ste on 9 Mar 2010 08:49
On 8 Mar, 22:55, PD <thedraperfam...(a)gmail.com> wrote: > On Mar 6, 5:32 am, Ste <ste_ro...(a)hotmail.com> wrote: > > > What confuses me is that, if the clocks run slow by 2% for all the > > time that they are moving, how does one reconcile this with the fact > > that, if one uses the frame of one of the moving clocks, say clock B, > > then it seems to be to be your argument that there is no slowdown at > > all for B, and it is the other clocks, A and C, that slow down (i.e. > > *disregarding* both acceleration and propagation delays). > > Be careful. The acceleration profiles are common between B and C, but > they are not common to A. So while there is no difference between B > and C due to the acceleration, you CANNOT say that the acceleration > has no effect whatsoever. In fact, it is the indisputable fact that B > and C accelerate and A does NOT accelerate that makes the situation > nonsymmetric for A. This is what makes the worldline for A straight, > and the worldline for B and C kinked. Yes, but we're supposed to have isolated the effect of acceleration, and disregarded it. And in any event, the more important question is the discrepancy between B and C. > Two places where I will try to intercept misconceptions. > 1. The first temptation is to say, well, if the kink is what's > responsible for the time dilation, then all the dilating must happen > during the acceleration. That is not the case. Note the time dilation > is different for B and C, even though they have the same kink (the > same acceleration profile). The fact that there IS a kink is what > makes the elapsed time less on B and C than it is on A (where there is > no kink), but how much less depends on the steepness and length of the > straight parts of the worldline on either side of the kink. As I say, I've stipulated that we are measuring on the outbound journey, before any of the clocks have turned back. So we've had one episode of acceleration and now B and C are travelling at the same speed away from the origin point, but in opposite directions. What amount of time dilation does C suffer relative to B? Nil? 2%? 4%? > 2. The second temptation is to say, well, in B's frame it does not > accelerate, and A does accelerate. This is not correct. I know. > Now, it IS fair to say that while the clock B is on its outward > journey at constant speed, it can look back at clock A and discern > that clock A is running slow relative to B. And the same goes on the > inbound journey. And so it's a fair question to say, how does it > happen then that by the time B lands back at A, it is BEHIND clock A? > And here is where things do get interesting in terms of what B sees in > terms of the clock reading on A in the turnaround. No, the question is between B and C, not B and A. I'm using B and C specifically in order to allow us to disregard any effects of acceleration. And we've already stipulated that, if B and C have the same acceleration profiles and travel the same distance before returning to A, then they will be in agreement with each other, but both will have slowed relative to A. The question is, while they are still on the outbound journey, what do B and C report about each other? Do they both agree with each other still? Or not? |