Joan-Claude van Dirk Helps to Trivialize Special Relativity
in [Relativity]
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From: Daryl McCullough on 22 Mar 2005 09:33 cadwgan_gedrych(a)yahoo.com says... >Here is what it means: >Intrinsic atomic clock rhythm = >1 time unit per 1 atomic vibration. I don't know what that's supposed to mean. How do you measure time units, if not by counting atomic vibrations (or using some other periodic process)? >Therefore, clocks which when directly compared have >different readings when they once had identical readings >with no acceleration involved must have different intrinsic >clock rhythms. That's incorrect. Here's an analogy: You and I are both making a trip from New York City to Chicago, but by different routes. You drive straight west, while I drive southwest to Atlanta, and then northwest to Chicago. When we get together in Chicago, we compare odometer readings. My odometer shows more miles for the trip than yours does. Does that mean that my odometer has a different, faster "rhythm" than yours? No, it just means that my trip had a different length than yours. In Special Relativity, the same is true of elapsed (clock) time. Different paths through spacetime have different elapsed times, just like different paths through space have different lengths. >In the Triplet Paradox case (given by Throop at >http://mentock.home.mindspring.com/twins.htm), >the only SR explanation for the different ages at >the end is "they were in different frames." No, that's not the SR explanation. The SR explanation is that different paths through spacetime have different elapsed times, in the same way that different paths through space have different lengths. Elapsed time is a geometric property in SR, in the same way that path length is a geometric property. >As I said, SR does not pertain to intrinsic clock >rhythms or to intrinsic aging of people. All SR >can do is to offer the non-explanation that the >clocks and/or people were in different frames. The goal of SR (and science, in general) is not to "explain", but to describe nature. Whether a description counts as an explanation or not is *psychological*, not scientific. The scientific aspect of a theory is the extent to which it makes definite predictions that are born out by experiment. "Intrinsic clock rhythm" is not something that is observable, so it's not required that a scientific theory say anything at all about it. -- Daryl McCullough Ithaca, NY
From: cadwgan_gedrych on 22 Mar 2005 11:03 Daryl McCullough wrote: > > Take two identical atomic clocks. Take them out into > outer space far from atmosphere, far from any source > of gravity. Let one clock remain at rest in an inertial > frame. Put the second clock on a high speed rocket, and > take it on a outward-bound trip at speed v for a year, > and then back at speed v. After the two clocks are > reunited, compare the elapsed times on the two clocks. > Let T1 be the elapsed time on the first clock, and let > T2 be the elapsed time on the second clock. > > If I predict that T2/T1 = square-root(1-(v/c)^2), that seems > like a falsifiable prediction to me. You seem to be claiming > that such a prediction isn't *really* a prediction of SR. Okay, > if you want to say that, go ahead. It's not important what you > call it. No, it is not a prediction of SR. By "it," I mean "intrinsic clock slowing," and that is to what your experiment pertained because when two clocks which were once synchronous became asynchronous upon direct comparison, this involves intrinsic clock rhythm differences or intrinsic clock slowing. A much better example (than your above) would have been Throop's web site http://mentock.home.mindspring.com/twins.htm Throop's use of 3 people (which is the same as the use of three clocks) eliminates any and all accelerations. If we eliminate gravity (as you and Throop did) and all accelerations (as Throop did), then all we have left to explain the Triplet Paradox is different twin motions (or different clock motions) through space. However, as you well know, SR denies all meaning to the notion of motion through space. This raises the question So how did intrinsic clock slowing get into SR? Answer: It was given via Einstein's mere acceptance as experimental facts round-trip light speed invariance and isotropy before creating SR. Since intrinsic clock slowing is the most probable cause of timed round-trip light speed invariance, we see that Einstein's up-front acceptance of such invariance caused intrinsic clock slowing to be incorporated into SR, *despite* his firm denial that clocks do not intrinsically slow due to motion through space. Thus, contrary to your claim, intrinsic clock slowing was not a prediction of SR because it was merely given as an experimental result _before_ or prior to SR.
From: Daryl McCullough on 22 Mar 2005 11:27 cadwgan_gedrych(a)yahoo.com says... >This raises the question So how did intrinsic clock slowing >get into SR? There is no such thing in SR. -- Daryl McCullough Ithaca, NY
From: PDraper on 22 Mar 2005 11:48 On 3/22/05 9:45 AM, in article 1111502719.486342.221400(a)o13g2000cwo.googlegroups.com, "cadwgan_gedrych(a)yahoo.com" <cadwgan_gedrych(a)yahoo.com> wrote: > PD wrote: >> cadwgan_gedr...(a)yahoo.com wrote: >>> [1] Prove that SR says anything predictive about intrinsic >>> or physical clock rhythms. >> >> SR does not say anything predictive about intrinsic clock rhythms, as >> far as I know, nor does it claim to. Intrinsic clock rhythms are >> governed by physical laws, which must be Lorentz-invariant. However, >> this does NOT mean that physical clock rhythms are reflected in time >> measurements. > > Sorry, but your last sentence tells me that this conversion > must end now. You are too far off the wall for me. > I'm not surprised you think so. Special relativity and the non-absoluteness of time interval between two events or synchronicity seems to be too off the wall for you, too. PD
From: harry on 23 Mar 2005 05:26
Bilge wrote: > Harry: > >"Bilge" <dubious(a)radioactivex.lebesque-al.net> wrote in message > > >> > >> And the aforementioned experiment shows that there is no > >> ``correct choice.'' Events which are simultaneous in one frame > >> are simultaneous in _every_ frame. > > > >You mean, they are *out of sync* according to the calibration of *every > >other* frame - or your experiment is different from this one of PD. > > Exactly. What you fail to understand is that any to events connected > by a signal which propagates with less than infinite velocity are not > simultaneous in that case. I wonder why you think that I fail to understand that out of sync is called asynchronous... > [...] > > >> ought to be able to > >> grasp the reason why. Anything which can have any effect on anything > >> in this universe, has to be measureable in principle, since by definition, > >> an effect is the outcome of an experiment. > > > >Now that's too the point. There is a difference between measuring something > >with our toolbox, and inferring cause and effect. > >And it seems that you agree that what we measure are effects, from which we > >infer causes. > > The existence of an effect is not sufficient to infer a cause. I meant a cause in general. If you mean with "a cause", a specific proposed cause, I agree. Or do you pretend that things may just happen without any cause? > In order > to infer a cause, you first need a theory which quantifies the effect and > tells you what parameters of an experiment can be manipulated in such a > way that the effect is correlated with changing those parameters. Finally, > you need data that demonstrates that correlation. That is why it is so > difficult to do any experiment which provides evidence for new physics. > You first have to eliminate any possibility that existing physics doesn't > already contain the explanation. You can't simply attribute a physical > effect to a lack of desire to perform a difficult calculation or to a cause > which cannot be quantified physically. Anything which is physical can, > in principle, be manipilated by physical means through an experiment > and quantified. If you can't affect some physical quantity, it can't > affect you, since those are one and the same. I agree except for the last phrase: there you again confuse cause and effect. "I can't affect the sun, therefore it can't affect me"??! > >But necessarily the causes of what we can measure can logically not be > >measured, except if they themselves are effects. > >In the end we may expect that causes exist that can't be measured, but that > >can be inferred. > > Only if you believe it's turtles all the way down, in which case, > you might as throw your hands up in despair, declare science to have > no point and go to work for a pr firm. I think that there is a limit. But that makes no difference for this! > >> Explain how something can affect physical objects, yet conspire to not > >> affect the physical objects of an experiment. > > > >See above. Nothing is suggested to exist and that is useful for physics but > >that has no effect. > > You are suggesting exactly that. You are trying to avoid quantifying > the elements that make up the ontology of a theory by removing the > cause to the cause of a cause which is unquantifiable. That simply > adds a literal ``nothing'' to the theory. That sounds like garble to me. If you mean that physics can't describe all, I agree. > >> >> 3. No test has been able to distinguish which choice is correct. > >> > > >> >Correct, AFAIK. > >> > >> Incorrect. The article below reports an experiment that demonstrates > >> quantum correlations over a spacelike interval using moving beam > >> splitters, are completely independent of any time ordering assigned > >> to the measurements over that spacelike interval. > > > >"Incorrect" would imply, if I read him well, that an absolute reference > >frame has be measured. > > As usual, you do your best to read anything but what has been written. > ``Incorrect'' means that a test has been performed to determine which > choice is correct and what it determined is that no choice for an > absolute frame is correct. By the way, the outcome was exactly the > opposite of what the author had proposed. You mean that you read anything in what I have written! I stated that IMO PD's third point was correct, AFAIK. Harald |