Is Length Contraction in SR physical??
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From: kenseto on 8 Feb 2010 13:38 On Feb 8, 11:42 am, PD <thedraperfam...(a)gmail.com> wrote: > On Feb 7, 7:34 am, kenseto <kens...(a)erinet.com> wrote: > > > > > > > On Feb 6, 10:57 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Feb 6, 9:02 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > On 6 Feb, 17:16, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > On Feb 5, 8:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > On 5 Feb, 16:00, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > On Feb 4, 9:57 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > On 5 Feb, 02:48, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > > > > > > > > wrote: > > > > > > > > > > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > > > > > > > > >news:3979bca1-a35e-4399-bc71-75d2fc680757(a)21g2000yqj.googlegroups.com... > > > > > > > > > On 5 Feb, 01:12, artful <artful...(a)hotmail.com> wrote: > > > > > > > > > > > On Feb 5, 11:49 am, kenseto <kens...(a)erinet.com> wrote: > > > > > > > > > > > > On Feb 4, 6:04 pm, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > > > > > > > > On Feb 4, 5:59 pm, "kens...(a)erinet.com" <kens...(a)erinet.com> wrote: > > > > > > > > > > > > > > It it does violate the PoR. You made the contradcictory claims that > > > > > > > > > > > > > the pole can fit into the barn physically (materially) an at the > > > > > > > > > > > > > same > > > > > > > > > > > > > time you claim that the pole cannot fit into the barn physically > > > > > > > > > > > > > (materially)......that a violation of the PoR. > > > > > > > > > > > > > No. The doors are not closed simultaneously in the pole's frame, nor > > > > > > > > > > > > are the two ends of the pole simultaneously in the barn in the pole's > > > > > > > > > > > > reference frame. In the barn's frame, the two ends of the pole are in > > > > > > > > > > > > the barn simultaneously and the doors shut simultaneously. In the > > > > > > > > > > > > pole's frame, the two ends of the pole are in the barn at different > > > > > > > > > > > > times and the doors shut at different times. > > > > > > > > > > > > Sigh..You are making the contradictory claims: > > > > > > > > > > > 1. The pole can fit into the barn with both doors close > > > > > > > > > > > simultaneously. > > > > > > > > > > > In the frame of the barn > > > > > > > > > > > > 2. The pole cannot fit into the barn with both doors close > > > > > > > > > > > simultaneously. > > > > > > > > > > > In the frame of the pole > > > > > > > > > > > Two different meanings for 'simultaneously'. So they are not > > > > > > > > > > contradictory > > > > > > > > > > > You really are not very good at thinking or arguing logically. > > > > > > > > > > He seems perfectly reasonable to me. > > > > > > > > > > He's saying that, if one stands in the middle of the barn equidistant > > > > > > > > > from the doors on each side, and one closes the doors simultaneously > > > > > > > > > (i.e. what I would call "absolutely simultaneously", but which for > > > > > > > > > conveience we'll say "simultaneous according to an observer standing > > > > > > > > > equidistant from each door), then is it possible that both doors can > > > > > > > > > appear closed while the ladder is observed to be inside the barn. > > > > > > > > > > It's a simple question, and the answer is "no!". > > > > > > > > > > ______________________________ > > > > > > > > > Its a simple question, and the answer is "yes". It is quite easy to devise > > > > > > > > > an inertial frame in which the doors both appear closed and the ladder is > > > > > > > > > fully contained in the barn. > > > > > > > > > The question wasn't whether "an inertial frame can be devised...". > > > > > > > > Even I can think of situations where it would *appear* that the ladder > > > > > > > > was inside and both doors closed. The question is whether this is an > > > > > > > > artefact of observation, or whether the ladder is actually inside with > > > > > > > > both doors closed. The answer remains "no, the ladder does not fit > > > > > > > > inside with both doors closed". > > > > > > > > There is a simple test. > > > > > > > We can determine whether the doors closed simultaneously. We do this > > > > > > > using the test of simultaneity I indicated to you above: > > > > > > > 1. Have the door-closings generate signals that travel at identical > > > > > > > speeds from either event. > > > > > > > 2. Have a detector positioned at equal distance from the barn doors. > > > > > > > 3. If the detector receives the signals from the barn door-closings at > > > > > > > the same time, then the two doors closed simultaneously unambiguously. > > > > > > > You and I have agreed on this procedure. > > > > > > > If the detector is stationary, then yes we agree that this determines > > > > > > simultaneity. > > > > > > > > Secondly, we can determine whether any part of the pole was outside > > > > > > > the barn when those doors were closed by looking for the marks the > > > > > > > ends of the pole would have made on the door. In the absence of those > > > > > > > marks, we can safely conclude that the entire pole was inside the barn > > > > > > > at the time the doors were closed. > > > > > > > Agreed. I would expect this test is definitive, were it possible to > > > > > > carry out. > > > > > > And this has been tested in equivalent experiment. Documented. > > > > > Has it really? Which experiment was that, because my sources say that > > > > length contraction has *never* been experimentally observed. > > > > I already told you the answer to that. Please look again. > > > > > > Seto does not read experimental papers, because he finds them > > > > > confusing. So instead he believes what makes sense to him, rather than > > > > > letting experimental results tell him something different. > > > > > You have to concede at least the possibility Paul that the reason Ken > > > > finds them confusing, and so do I, is because *we* can see that they > > > > rest on certain assumptions. That is, assumptions that you've > > > > internalised, and assumptions which me and Ken reject. > > > > In Seto's case, it has more to do with thinking that SR says something > > > it does not. I haven't yet figured out whether you are in the same > > > boat. > > > The only assumptions I make are those that have testable consequences.. > > > Which ones of those do you think I have that you reject? > > > So are you saying that SR doesn't say that the pole can be completely > > inside the barn with both doors close simultaneously? > > SR *certainly* does not say that this statement holds true in both > barn frame and pole frame. > If you thought it did, then you never understood what SR says. I didn't say that that statement hold true in both barn and pole frame. I said that SR claim that the pole is physically contracted so that it can fit into the barn and that SR also made the contradictory assertion that the same pole is not physically contracted so that it is not able to fit into the barn. > > > I ask this > > question because that's what I think SR says. > > You are wrong about that.- Hide quoted text - > > - Show quoted text -
From: PD on 8 Feb 2010 15:09 On Feb 8, 12:38 pm, kenseto <kens...(a)erinet.com> wrote: > On Feb 8, 11:42 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 7, 7:34 am, kenseto <kens...(a)erinet.com> wrote: > > > > On Feb 6, 10:57 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Feb 6, 9:02 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > On 6 Feb, 17:16, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Feb 5, 8:14 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > On 5 Feb, 16:00, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > On Feb 4, 9:57 pm, Ste <ste_ro...(a)hotmail.com> wrote: > > > > > > > > > > On 5 Feb, 02:48, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > > > > > > > > > wrote: > > > > > > > > > > > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > > > > > > > > > >news:3979bca1-a35e-4399-bc71-75d2fc680757(a)21g2000yqj.googlegroups.com... > > > > > > > > > > On 5 Feb, 01:12, artful <artful...(a)hotmail.com> wrote: > > > > > > > > > > > > On Feb 5, 11:49 am, kenseto <kens...(a)erinet.com> wrote: > > > > > > > > > > > > > On Feb 4, 6:04 pm, mpalenik <markpale...(a)gmail.com> wrote: > > > > > > > > > > > > > > On Feb 4, 5:59 pm, "kens...(a)erinet.com" <kens...(a)erinet.com> wrote: > > > > > > > > > > > > > > > It it does violate the PoR. You made the contradcictory claims that > > > > > > > > > > > > > > the pole can fit into the barn physically (materially) an at the > > > > > > > > > > > > > > same > > > > > > > > > > > > > > time you claim that the pole cannot fit into the barn physically > > > > > > > > > > > > > > (materially)......that a violation of the PoR. > > > > > > > > > > > > > > No. The doors are not closed simultaneously in the pole's frame, nor > > > > > > > > > > > > > are the two ends of the pole simultaneously in the barn in the pole's > > > > > > > > > > > > > reference frame. In the barn's frame, the two ends of the pole are in > > > > > > > > > > > > > the barn simultaneously and the doors shut simultaneously. In the > > > > > > > > > > > > > pole's frame, the two ends of the pole are in the barn at different > > > > > > > > > > > > > times and the doors shut at different times. > > > > > > > > > > > > > Sigh..You are making the contradictory claims: > > > > > > > > > > > > 1. The pole can fit into the barn with both doors close > > > > > > > > > > > > simultaneously. > > > > > > > > > > > > In the frame of the barn > > > > > > > > > > > > > 2. The pole cannot fit into the barn with both doors close > > > > > > > > > > > > simultaneously. > > > > > > > > > > > > In the frame of the pole > > > > > > > > > > > > Two different meanings for 'simultaneously'. So they are not > > > > > > > > > > > contradictory > > > > > > > > > > > > You really are not very good at thinking or arguing logically. > > > > > > > > > > > He seems perfectly reasonable to me. > > > > > > > > > > > He's saying that, if one stands in the middle of the barn equidistant > > > > > > > > > > from the doors on each side, and one closes the doors simultaneously > > > > > > > > > > (i.e. what I would call "absolutely simultaneously", but which for > > > > > > > > > > conveience we'll say "simultaneous according to an observer standing > > > > > > > > > > equidistant from each door), then is it possible that both doors can > > > > > > > > > > appear closed while the ladder is observed to be inside the barn. > > > > > > > > > > > It's a simple question, and the answer is "no!". > > > > > > > > > > > ______________________________ > > > > > > > > > > Its a simple question, and the answer is "yes". It is quite easy to devise > > > > > > > > > > an inertial frame in which the doors both appear closed and the ladder is > > > > > > > > > > fully contained in the barn. > > > > > > > > > > The question wasn't whether "an inertial frame can be devised...". > > > > > > > > > Even I can think of situations where it would *appear* that the ladder > > > > > > > > > was inside and both doors closed. The question is whether this is an > > > > > > > > > artefact of observation, or whether the ladder is actually inside with > > > > > > > > > both doors closed. The answer remains "no, the ladder does not fit > > > > > > > > > inside with both doors closed". > > > > > > > > > There is a simple test. > > > > > > > > We can determine whether the doors closed simultaneously. We do this > > > > > > > > using the test of simultaneity I indicated to you above: > > > > > > > > 1. Have the door-closings generate signals that travel at identical > > > > > > > > speeds from either event. > > > > > > > > 2. Have a detector positioned at equal distance from the barn doors. > > > > > > > > 3. If the detector receives the signals from the barn door-closings at > > > > > > > > the same time, then the two doors closed simultaneously unambiguously. > > > > > > > > You and I have agreed on this procedure. > > > > > > > > If the detector is stationary, then yes we agree that this determines > > > > > > > simultaneity. > > > > > > > > > Secondly, we can determine whether any part of the pole was outside > > > > > > > > the barn when those doors were closed by looking for the marks the > > > > > > > > ends of the pole would have made on the door. In the absence of those > > > > > > > > marks, we can safely conclude that the entire pole was inside the barn > > > > > > > > at the time the doors were closed. > > > > > > > > Agreed. I would expect this test is definitive, were it possible to > > > > > > > carry out. > > > > > > > And this has been tested in equivalent experiment. Documented. > > > > > > Has it really? Which experiment was that, because my sources say that > > > > > length contraction has *never* been experimentally observed. > > > > > I already told you the answer to that. Please look again. > > > > > > > Seto does not read experimental papers, because he finds them > > > > > > confusing. So instead he believes what makes sense to him, rather than > > > > > > letting experimental results tell him something different. > > > > > > You have to concede at least the possibility Paul that the reason Ken > > > > > finds them confusing, and so do I, is because *we* can see that they > > > > > rest on certain assumptions. That is, assumptions that you've > > > > > internalised, and assumptions which me and Ken reject. > > > > > In Seto's case, it has more to do with thinking that SR says something > > > > it does not. I haven't yet figured out whether you are in the same > > > > boat. > > > > The only assumptions I make are those that have testable consequences. > > > > Which ones of those do you think I have that you reject? > > > > So are you saying that SR doesn't say that the pole can be completely > > > inside the barn with both doors close simultaneously? > > > SR *certainly* does not say that this statement holds true in both > > barn frame and pole frame. > > If you thought it did, then you never understood what SR says. > > I didn't say that that statement hold true in both barn and pole > frame. Yes, you did. Two days ago you said just this: "The pole observer have to agree with the barn observer that the pole is completely inside the barn with both door close simultnaeously." You said they have to agree. They do not. That does not make a contradiction. > I said that SR claim that the pole is physically contracted so > that it can fit into the barn and that SR also made the contradictory > assertion that the same pole is not physically contracted so that it > is not able to fit into the barn. > > > > > > I ask this > > > question because that's what I think SR says. > > > You are wrong about that.- Hide quoted text - > > > - Show quoted text -
From: PD on 8 Feb 2010 15:21 On Feb 8, 3:57 am, Ste <ste_ro...(a)hotmail.com> wrote: > > Indeed, I have no information about how the decay products are > measured in these accelerators nor access to the raw data set, and I'm > not willing to take the word of scientific authority in which I have > utterly no faith, particularly because so many supposed experts appear > to have no insight whatsoever into the physical nature of their > mathematical models, and even more shockingly the request for a > physical explanation often produces the reply "what do you mean by > physical", as though it needed to be defined! Well, here we run into the small conundrum: S: "I don't see why I should believe this theory without a physical model that makes sense to me." P: "Well, you see, physicists choose which model to believe based on which of the models matches the largest set of experimental data." S: "But I don't believe the experimental data either, because I do not trust that they haven't been skewed by physicists." P: "What would it take for you to believe the experimental data?" S: "It would require physicists to explain the data with a model that makes sense to me." Self-fulfilling prophecy, you see.
From: PD on 8 Feb 2010 15:23 On Feb 7, 9:55 pm, Ste <ste_ro...(a)hotmail.com> wrote: > On 7 Feb, 22:48, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > wrote: > > > > > "Ste" <ste_ro...(a)hotmail.com> wrote in message > > >news:807a38a6-210c-4b5a-9ae0-388f623f391a(a)b10g2000yqa.googlegroups.com.... > > > > On 7 Feb, 07:08, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> > > > wrote: > > >> "Ste" <ste_ro...(a)hotmail.com> wrote in message > > > >> >> _________________________________ > > >> >> Lots of ways. Normally I measure length by puting a ruler next to an > > >> >> object. > > > >> > And by looking at the readings with your eyes no doubt - so we've gone > > >> > back to a measurement mediated by light? > > > >> No, I feel the edges with my fingers. Blind people can still measure > > >> things. > > > > Ain't that the truth about physicists! But seriously, yes you can > > > feel, but the fact remains that no "feeling" experiment has ever been > > > done. > > > Huh? > > > Your complaint about SR is that the experiments have never been conducted by > > a blind person using touch alone? > > No, my complaint is about the people who keep insisting that SR > represents something more fundamental than a description of the > behaviour of EMR. And what is the basis of your complaint? Why do you think it is NOT so?
From: PD on 8 Feb 2010 15:25
On Feb 7, 8:39 am, kenseto <kens...(a)erinet.com> wrote: > > > When Ken started asking these questions 15 years ago, they were > > reasonable questions. When after a couple of years it was clear he was > > not listening to the answers given to his questions, the tone of the > > responses became a little different. > > Why should I listen to what you said when you did made sense.?? Ken, it isn't wise to stop listening to people if you do not understand what they are saying. It would be important in that case to say, "I don't understand what you are saying. Can you explain it differently so I can understand it?" |