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 8 Mar 2010 01:31 "Bruce Richmond" <bsr3997(a)my-deja.com> wrote in message news:e4af970e-c2d2-47ac-934b-f5801d5e85ec(a)m37g2000yqf.googlegroups.com... On Mar 7, 9:47 pm, "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote: > "Bruce Richmond" <bsr3...(a)my-deja.com> wrote in message > > news:1c6a2640-39f5-4ea4-9c85-127e71f4e6a2(a)33g2000yqj.googlegroups.com... > On Mar 7, 6:58 pm, "Inertial" <relativ...(a)rest.com> wrote: > > > > > > > "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message > > >news:4b943853$0$11336$afc38c87(a)news.optusnet.com.au... > > > > "Inertial" <relativ...(a)rest.com> wrote in message > > >news:4b942bcf$0$27789$c3e8da3(a)news.astraweb.com... > > >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message > > >>news:4b93bf73$0$28464$afc38c87(a)news.optusnet.com.au... > > > >>>>> 1) your statement: "For clarity, both effects are purely > > >>>>> observational - SR presumes (ideal) clock mechanisms are > > >>>>> completely > > >>>>> unaffected by a clock's motion." -- I agree the physical mechanism > > >>>>> of > > >>>>> the clock is unaffected, but this is a really misleading > > >>>>> statement, > > >>>>> since the amount of proper time that the clock consumes is > > >>>>> affected > > >>>>> by > > >>>>> its motion. Are you trying to say > > > >>>> I was "trying to say" exactly what I did say. If you didn't find it > > >>>> clear enough, try this: relative slow-downs/speed-ups observed in > > >>>> the > > >>>> readings of SR's ideal clocks aren't due to changes in the tick > > >>>> mechanisms of those clocks. > > > >>> I still don't find it clear, as it begs the question - it says what > > >>> doesn't cause the change, not what does cause the change. > > > >>> The standard SR answer is much more direct - the clocks slow down > > >>> due > > >>> to > > >>> relativistic time dilatation from them being in different reference > > >>> frames. > > > >>> Is that standard position of SR also your position? Or is your > > >>> somehow > > >>> different? > > > >> SR says that the difference in clock sync (clock settings) cause the > > >> measurement of length to be contracted and measurement of clock > > >> ticking > > >> rates to be dilated. > > > > More or less. > > > That's what it is :) > > > > But I asked you about *your* position, not SR's position. > > > My position is SR's position > > > > Do you agree that that the clocks slow down due to relativistic time > > > dilation, as predicted by SR, or not? > > > They are measured as slower, just as a rod is measured as shorter. This > > is > > due to the difference in simultaneity. They don't slow down because a > > moving observer is looking at them any more than a rod shrinks because a > > relatively moving observer is looking at it. > > > Here's a little example you might follow .. with time differences > > exagerated > > for clarity > > > Here are six clocks, in tow rows (S and S'), all ticking at the correct > > rate, but set with different times... > > > S' 10:30 11:00=A 11:30 <--v > > S 11:30=C 11:00=B 10:30 -->v > > > Clocks B sees the A is synchronized with it. > > > Now .. the clocks are moving in opposite directions so after an hour we > > have > > > S' 11:30 12:00=A 12:30 > > S 12:30=C 12:00=B 11:30 > > > Clock A has moved away from clock B .. but another clock (C) in S can > > see > > the time on it. Clock C sees that clock A is half an hour slow (A shows > > 12:00 when C shows 12:30). So according to the clocks in S, clock A is > > ticking slower. We also note that clock B now sees a *different* S' > > clock > > next to it as being fast (it shows 12:30 when B shows 12:00) > > > If you look at the same scenario but from the point of view of the other > > row > > of clocks, you get symmetric results. > > > This is how clock synch affects measured ticking rates for moving clocks > > in > > SR. Even though the clocks themselves do NOT change their intrinsic > > ticking > > rates.- Hide quoted text - > > Looks good, but let's take it one step further. The observer with > clock A jumps to frame S" which is traveling in the same direction as > S relative to S' but at twice the velocity. > > S" 1:00 12:00=A 11:00 -->2v > S' 11:30 12:00=A 12:30 <--v > S 12:30=C 12:00=B 11:30 -->v > > Clocks A and B continue to tick at there same intrinsic ticking rate > and an hour later A has overtaken B. > > S" 2:00 1:00=A 12:00 -->2v > S' 12:30 1:00=A 1:30 <--v > S 1:30=C 1:00=B 12:30 -->v > > The above provides the same situation as the twins paradox. Clock A > left clock B and returned. So why doesn't clock A show less time > elapsed than B? (Note the clocks in S" are further out of sync than > those in S due to the higher velocity.) > > _________________________________________ > I can't exactly follow your experiment or its conclusions. > > But, if as you say, it is the same situation as the twins paradox, > thenhttp://en.wikipedia.org/wiki/Twin_paradoxshould explain it. > > More generally, once you understand the "normal" twins paradox, and the > diagrams on the web page, it is very simple to change this to model > additional frames-of-reference, either by simpy adding a third object to > the > diagrams or considering the various objects in pairs. > > If, OTOH, you don't understand the "vanilla" twins paradox, making it more > complicated won't help. > > So, as a starting point, do you understand and accept the resolution of > the > "vanilla" twins paradox as explained > athttp://en.wikipedia.org/wiki/Twin_paradoxand many other reputable > sites?- Hide quoted text - For starters it wasn't my experiment. As for it being the same as the twins paradox, clock A left clock B and then returned to clock B while clock B stayed inertial the whole time. I think we can agree that is a perfect description of the twins paradox. I understand the "vanilla" twins paradox. It is often explained using light clocks with a photon bouncing vertically between mirrors as the twin moves horizontally. The moving photon follows a zig zag path that is longer than the vertical path of the stationary twin, resulting in fewer ticks during the trip than the stationary twin. In that presentation the moving clock does tick slower. __________________________________ Excellent. You should have no problem. Inertial started with clocks A and B moving in opposit directions at the same speed, so their clock photons would plot symetric paths in opposit directions, yeilding the same tick rate. Combine that with the clock sync and you can show how the clock sync creates mutual time dialation with the clocks tick rate unchanged by the motion of the clock. But adding the turn around shows that the clocks are affected by their motion. If clock A continues to tick at the same rate, as Inertial claimed it would, then it would read the same as clock B when they met up again. If OTOH you consider that the zig zag path of the photon in clock A gets streched out further, resulting in a slower tick rate, you get clock A showing less time than clock B when they get back together. ___________________________________ I still don't understand the experimental design. Try explaining it without your own editorial about zizagging photons, or your own predictions as to what might result. For example: "Two clocks B and C are sent in opposite directions at 0.9c for 1 second, at the end of the 1 second they reverse direction and head back to the origon at 0.9c for another second, when they meet again at the origon, how would their times compare with each other and a reference clock A that stayed at the origin and didn't move"? If that in fact is your question, then both B and C will show the same elapsed time, which will be a bit over a second less elapsed time than shown by clock A. If that is not your question, if you are able to state it simply as per my example I am happy to help. I'm not trying to be a troll here. I agree that clock A should show less elapsed time than clock B when they get back together. I also agree that the primary cause for the measured slowing of moving clocks is the syncronization of the clocks doing the measuring. But from what I see that can't be the only reason or there would be no age difference when the twin returns. In the Wiki explaination it says of the turn around, "That is when he must adjust his calculated age of the twin at rest." That calculation doesn't change his age any more than the intrinsic length of a rod is changed by an observer looking at it. ____________________________________ The turnaround is when things have to be recalculated, because he has changed intertial frames. His age is a function of the inertial reference frame in which it is measured. Exactly this happens every day when the age s measured of unstable sub-atomic particles in pareticle accelerators or in cosmic ray debris. Bruce
From: Peter Webb on 8 Mar 2010 01:38 "Bruce Richmond" <bsr3997(a)my-deja.com> wrote in message news:29fd9f7d-c9b4-41e6-b33a-585c3e0e7acf(a)q23g2000yqd.googlegroups.com... On Mar 7, 9:48 pm, "Inertial" <relativ...(a)rest.com> wrote: > "Bruce Richmond" <bsr3...(a)my-deja.com> wrote in message > > news:1c6a2640-39f5-4ea4-9c85-127e71f4e6a2(a)33g2000yqj.googlegroups.com... > > > > > > > On Mar 7, 6:58 pm, "Inertial" <relativ...(a)rest.com> wrote: > >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message > > >>news:4b943853$0$11336$afc38c87(a)news.optusnet.com.au... > > >> > "Inertial" <relativ...(a)rest.com> wrote in message > >> >news:4b942bcf$0$27789$c3e8da3(a)news.astraweb.com... > >> >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message > >> >>news:4b93bf73$0$28464$afc38c87(a)news.optusnet.com.au... > > >> >>>>> 1) your statement: "For clarity, both effects are purely > >> >>>>> observational - SR presumes (ideal) clock mechanisms are > >> >>>>> completely > >> >>>>> unaffected by a clock's motion." -- I agree the physical > >> >>>>> mechanism > >> >>>>> of > >> >>>>> the clock is unaffected, but this is a really misleading > >> >>>>> statement, > >> >>>>> since the amount of proper time that the clock consumes is > >> >>>>> affected > >> >>>>> by > >> >>>>> its motion. Are you trying to say > > >> >>>> I was "trying to say" exactly what I did say. If you didn't find > >> >>>> it > >> >>>> clear enough, try this: relative slow-downs/speed-ups observed in > >> >>>> the > >> >>>> readings of SR's ideal clocks aren't due to changes in the tick > >> >>>> mechanisms of those clocks. > > >> >>> I still don't find it clear, as it begs the question - it says what > >> >>> doesn't cause the change, not what does cause the change. > > >> >>> The standard SR answer is much more direct - the clocks slow down > >> >>> due > >> >>> to > >> >>> relativistic time dilatation from them being in different reference > >> >>> frames. > > >> >>> Is that standard position of SR also your position? Or is your > >> >>> somehow > >> >>> different? > > >> >> SR says that the difference in clock sync (clock settings) cause the > >> >> measurement of length to be contracted and measurement of clock > >> >> ticking > >> >> rates to be dilated. > > >> > More or less. > > >> That's what it is :) > > >> > But I asked you about *your* position, not SR's position. > > >> My position is SR's position > > >> > Do you agree that that the clocks slow down due to relativistic time > >> > dilation, as predicted by SR, or not? > > >> They are measured as slower, just as a rod is measured as shorter. This > >> is > >> due to the difference in simultaneity. They don't slow down because a > >> moving observer is looking at them any more than a rod shrinks because > >> a > >> relatively moving observer is looking at it. > > >> Here's a little example you might follow .. with time differences > >> exagerated > >> for clarity > > >> Here are six clocks, in tow rows (S and S'), all ticking at the correct > >> rate, but set with different times... > > >> S' 10:30 11:00=A 11:30 <--v > >> S 11:30=C 11:00=B 10:30 -->v > > >> Clocks B sees the A is synchronized with it. > > >> Now .. the clocks are moving in opposite directions so after an hour we > >> have > > >> S' 11:30 12:00=A 12:30 > >> S 12:30=C 12:00=B 11:30 > > >> Clock A has moved away from clock B .. but another clock (C) in S can > >> see > >> the time on it. Clock C sees that clock A is half an hour slow (A shows > >> 12:00 when C shows 12:30). So according to the clocks in S, clock A is > >> ticking slower. We also note that clock B now sees a *different* S' > >> clock > >> next to it as being fast (it shows 12:30 when B shows 12:00) > > >> If you look at the same scenario but from the point of view of the > >> other > >> row > >> of clocks, you get symmetric results. > > >> This is how clock synch affects measured ticking rates for moving > >> clocks > >> in > >> SR. Even though the clocks themselves do NOT change their intrinsic > >> ticking > >> rates.- Hide quoted text - > > > Looks good, but let's take it one step further. The observer with > > clock A jumps to frame S" which is traveling in the same direction as > > S relative to S' but at twice the velocity. > > > S" 1:00 12:00=A 11:00 -->2v > > S' 11:30 12:00=A 12:30 <--v > > S 12:30=C 12:00=B 11:30 -->v > > > Clocks A and B continue to tick at there same intrinsic ticking rate > > and an hour later A has overtaken B. > > > S" 2:00 1:00=A 12:00 -->2v > > S' 12:30 1:00=A 1:30 <--v > > S 1:30=C 1:00=B 12:30 -->v > > > The above provides the same situation as the twins paradox. Clock A > > left clock B and returned. So why doesn't clock A show less time > > elapsed than B? (Note the clocks in S" are further out of sync than > > those in S due to the higher velocity.) > > The three clock situation cannot be so easily drawn .. bit like trying to > drawing a three dimensional figure in 2d :) This sort of diagram only > really works for a single pair of clocks looking from a third frame in > which > they move with the same speed. Things are trickier when there is frame > jumping going on :):)- Hide quoted text - > > - Show quoted text - The question still remains, if there is no change in the tick rate of the clock, how can clock A have fewer ticks recorded when it is brought back to clock B? Bruce _________________________________ Again, state your experimental design exactly. It should be quite easy to say exactly what SR would predict happening. If you do not understand or agree with what SR predicts, we can go through it step by step in the same manner as for the vanilla twins paradox.
From: G. L. Bradford on 8 Mar 2010 01:38 "Bruce Richmond" <bsr3997(a)my-deja.com> wrote in message news:1c6a2640-39f5-4ea4-9c85-127e71f4e6a2(a)33g2000yqj.googlegroups.com... On Mar 7, 6:58 pm, "Inertial" <relativ...(a)rest.com> wrote: > "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message > > news:4b943853$0$11336$afc38c87(a)news.optusnet.com.au... > > > > > > > > > "Inertial" <relativ...(a)rest.com> wrote in message > >news:4b942bcf$0$27789$c3e8da3(a)news.astraweb.com... > >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message > >>news:4b93bf73$0$28464$afc38c87(a)news.optusnet.com.au... > > >>>>> 1) your statement: "For clarity, both effects are purely > >>>>> observational - SR presumes (ideal) clock mechanisms are completely > >>>>> unaffected by a clock's motion." -- I agree the physical mechanism > >>>>> of > >>>>> the clock is unaffected, but this is a really misleading statement, > >>>>> since the amount of proper time that the clock consumes is affected > >>>>> by > >>>>> its motion. Are you trying to say > > >>>> I was "trying to say" exactly what I did say. If you didn't find it > >>>> clear enough, try this: relative slow-downs/speed-ups observed in the > >>>> readings of SR's ideal clocks aren't due to changes in the tick > >>>> mechanisms of those clocks. > > >>> I still don't find it clear, as it begs the question - it says what > >>> doesn't cause the change, not what does cause the change. > > >>> The standard SR answer is much more direct - the clocks slow down due > >>> to > >>> relativistic time dilatation from them being in different reference > >>> frames. > > >>> Is that standard position of SR also your position? Or is your somehow > >>> different? > > >> SR says that the difference in clock sync (clock settings) cause the > >> measurement of length to be contracted and measurement of clock ticking > >> rates to be dilated. > > > More or less. > > That's what it is :) > > > But I asked you about *your* position, not SR's position. > > My position is SR's position > > > Do you agree that that the clocks slow down due to relativistic time > > dilation, as predicted by SR, or not? > > They are measured as slower, just as a rod is measured as shorter. This is > due to the difference in simultaneity. They don't slow down because a > moving observer is looking at them any more than a rod shrinks because a > relatively moving observer is looking at it. > > Here's a little example you might follow .. with time differences > exagerated > for clarity > > Here are six clocks, in tow rows (S and S'), all ticking at the correct > rate, but set with different times... > > S' 10:30 11:00=A 11:30 <--v > S 11:30=C 11:00=B 10:30 -->v > > Clocks B sees the A is synchronized with it. > > Now .. the clocks are moving in opposite directions so after an hour we > have > > S' 11:30 12:00=A 12:30 > S 12:30=C 12:00=B 11:30 > > Clock A has moved away from clock B .. but another clock (C) in S can see > the time on it. Clock C sees that clock A is half an hour slow (A shows > 12:00 when C shows 12:30). So according to the clocks in S, clock A is > ticking slower. We also note that clock B now sees a *different* S' clock > next to it as being fast (it shows 12:30 when B shows 12:00) > > If you look at the same scenario but from the point of view of the other > row > of clocks, you get symmetric results. > > This is how clock synch affects measured ticking rates for moving clocks > in > SR. Even though the clocks themselves do NOT change their intrinsic > ticking > rates.- Hide quoted text - Looks good, but let's take it one step further. The observer with clock A jumps to frame S" which is traveling in the same direction as S relative to S' but at twice the velocity. S" 1:00 12:00=A 11:00 -->2v S' 11:30 12:00=A 12:30 <--v S 12:30=C 12:00=B 11:30 -->v Clocks A and B continue to tick at there same intrinsic ticking rate and an hour later A has overtaken B. S" 2:00 1:00=A 12:00 -->2v S' 12:30 1:00=A 1:30 <--v S 1:30=C 1:00=B 12:30 -->v The above provides the same situation as the twins paradox. Clock A left clock B and returned. So why doesn't clock A show less time elapsed than B? (Note the clocks in S" are further out of sync than those in S due to the higher velocity.) ========================== Two clocks one light year apart that God certifies are in as perfect a sync as if each of them were sitting in the other's space would each have a year equal to 2010. But each observes the other to have the year 2009 as the year on the clock, not 2010. That year 2009, not 2010, is any traveler's starting block for any voyage to that destination ONE LIGHT YEAR FROM THE TRAVELER'S DEPARTURE POINT! You two like so many, many others totally ignore -- or are so totally ignorant of -- the LIGHT-TIME (the LIGHT-HISTORY) universe surrounding you! Light-time (light-history), light second by light second (second by historical second), light year by light year (year by historical year) that, really, would have to be accounted for in all travel. Even the slightest fraction of a light second (the slightest fraction of a historical second) has to be accounted for.....HAS TO BE PASSED OVER OR THROUGH! and thus observed, second of history by second of history, by second of history! Thus a ship departing planet A (March 2010) for planet B one light year away (thus observed time-date for planet B being Mar 2009), taking one year of ship's time to reach B (arrival scheduled for March 2011), has to deal with a time period during its space travel of Mar 2009, Apr 2009, May 2009........, Jan 2010, Feb 2010, Mar 2010, Apr 2010, May 2010......, Jan 2011, Feb 2011, to its arrival at planet B one light year away and one year later, March 2011. Ship's travel time per ship's clock, one year (Mar 2010-Mar 2011). Ship's travel time per closest observations made of the space-time of the external environment, the light-time of the external universe, two years (Mar 2009-Mar 2011). Upon arrival at planet B, what does the traveler observe of planet A? He observes Planet A one light year (or Mar 2010) in distance from planet B (or Mar 2011) where he stands now. The same as any of planet B's homebodies who never step foot, whatever, off planet. Even if you are just going to walk down the street, the merest fraction of a light second's distance, you are observing a historical universe (a light-time universe) extending out in every direction from the departure point, and you have to account for it each and every step of the walk. Your starting point (vis-a-vis the universe of light) is not the time on your watch or the time on the atomic clock you are standing next to, but the space-time in the universe you would observe for your destination (-) from where you stand (0). Arrival at your destination will have you at (0) from that originally observed distant (-). You traveled the history (-) (the light-time (-)) -- and the travel time -- all in the clocked time of your travel from A to B. In order to get from A to B, at all, you have to do some contracting, followed by expanding, of the universe. Some contracting / expanding of space and time (of space as well as time, both at once). Some contracting / expanding of the SINGLE ENTITY of space-time (out there especially, the single entity of light-time). Yes travelers do leap forward into the future, but they don't do that leap from the present. They leap forward into the future from the past. Any competent observer should know what he is observing at any distance from him, of course including all travelers, is history and not simultaneity. All travelers observed to be coming on out of the distances of the universe are observed to be fast forwarding (+) up through history (-) and cannot be observed to be coming on present (0) to present (0). All travelers observed to be going away are observed to be going away into the past (-), going away into that same history (-) above, observably becoming an observed piece (-) of that observed universe (-), and cannot be observed to be going away present (0) to present (0). Yet there are physicists who claim that all their observations of travelers are observations of the present of the travelers no matter how distant the travelers from them. And, the strangest and funniest thing of all is that they observe, and describe, exactly the same picture for their THERE-NOW "present" (0) of travelers that anyone else would be observing and describing for a THERE-THEN distance (-) in space-time concerning exactly the same travelers. Our distant THERE-THEN universe (-), and the equally distant THERE-THEN travelers in it (-), we observe and describe is exactly the same picture, exactly the same universe and travelers, as those particular physicists' no-distance-at-all (instantaneous) THERE-NOW universe (0), and the THERE-NOW travelers in it (0), they purport to observe and describe. What differences we observe for THERE-THEN and HERE-NOW, they claim exist for THERE-NOW and HERE-NOW. To go at it somewhat differently, ask them to describe the historical space-time the historical traveler is observed to be in at 200 light seconds from here and now, [versus] a forwardly projected picture of that traveler 200 seconds to the unobservable there-now space-time of the universe, and they will not do it. They cannot do it. They cannot project the traveler forward in space and time from a negative space-time picture. They cannot do a "versus" picture because the two pictures are exactly one, and the same, picture to them. They ascribe exactly the same negative time of the historical picture observed of the distant traveler to the literal physical being of the traveler who arrives home here on Earth. GLB ============================
From: Inertial on 8 Mar 2010 01:58 "Bruce Richmond" <bsr3997(a)my-deja.com> wrote in message news:29fd9f7d-c9b4-41e6-b33a-585c3e0e7acf(a)q23g2000yqd.googlegroups.com... > On Mar 7, 9:48 pm, "Inertial" <relativ...(a)rest.com> wrote: >> "Bruce Richmond" <bsr3...(a)my-deja.com> wrote in message >> >> news:1c6a2640-39f5-4ea4-9c85-127e71f4e6a2(a)33g2000yqj.googlegroups.com... >> >> >> >> >> >> > On Mar 7, 6:58 pm, "Inertial" <relativ...(a)rest.com> wrote: >> >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in message >> >> >>news:4b943853$0$11336$afc38c87(a)news.optusnet.com.au... >> >> >> > "Inertial" <relativ...(a)rest.com> wrote in message >> >> >news:4b942bcf$0$27789$c3e8da3(a)news.astraweb.com... >> >> >> "Peter Webb" <webbfam...(a)DIESPAMDIEoptusnet.com.au> wrote in >> >> >> message >> >> >>news:4b93bf73$0$28464$afc38c87(a)news.optusnet.com.au... >> >> >> >>>>> 1) your statement: "For clarity, both effects are purely >> >> >>>>> observational - SR presumes (ideal) clock mechanisms are >> >> >>>>> completely >> >> >>>>> unaffected by a clock's motion." -- I agree the physical >> >> >>>>> mechanism >> >> >>>>> of >> >> >>>>> the clock is unaffected, but this is a really misleading >> >> >>>>> statement, >> >> >>>>> since the amount of proper time that the clock consumes is >> >> >>>>> affected >> >> >>>>> by >> >> >>>>> its motion. Are you trying to say >> >> >> >>>> I was "trying to say" exactly what I did say. If you didn't find >> >> >>>> it >> >> >>>> clear enough, try this: relative slow-downs/speed-ups observed in >> >> >>>> the >> >> >>>> readings of SR's ideal clocks aren't due to changes in the tick >> >> >>>> mechanisms of those clocks. >> >> >> >>> I still don't find it clear, as it begs the question - it says >> >> >>> what >> >> >>> doesn't cause the change, not what does cause the change. >> >> >> >>> The standard SR answer is much more direct - the clocks slow down >> >> >>> due >> >> >>> to >> >> >>> relativistic time dilatation from them being in different >> >> >>> reference >> >> >>> frames. >> >> >> >>> Is that standard position of SR also your position? Or is your >> >> >>> somehow >> >> >>> different? >> >> >> >> SR says that the difference in clock sync (clock settings) cause >> >> >> the >> >> >> measurement of length to be contracted and measurement of clock >> >> >> ticking >> >> >> rates to be dilated. >> >> >> > More or less. >> >> >> That's what it is :) >> >> >> > But I asked you about *your* position, not SR's position. >> >> >> My position is SR's position >> >> >> > Do you agree that that the clocks slow down due to relativistic time >> >> > dilation, as predicted by SR, or not? >> >> >> They are measured as slower, just as a rod is measured as shorter. >> >> This >> >> is >> >> due to the difference in simultaneity. They don't slow down because a >> >> moving observer is looking at them any more than a rod shrinks because >> >> a >> >> relatively moving observer is looking at it. >> >> >> Here's a little example you might follow .. with time differences >> >> exagerated >> >> for clarity >> >> >> Here are six clocks, in tow rows (S and S'), all ticking at the >> >> correct >> >> rate, but set with different times... >> >> >> S' 10:30 11:00=A 11:30 <--v >> >> S 11:30=C 11:00=B 10:30 -->v >> >> >> Clocks B sees the A is synchronized with it. >> >> >> Now .. the clocks are moving in opposite directions so after an hour >> >> we >> >> have >> >> >> S' 11:30 12:00=A 12:30 >> >> S 12:30=C 12:00=B 11:30 >> >> >> Clock A has moved away from clock B .. but another clock (C) in S can >> >> see >> >> the time on it. Clock C sees that clock A is half an hour slow (A >> >> shows >> >> 12:00 when C shows 12:30). So according to the clocks in S, clock A >> >> is >> >> ticking slower. We also note that clock B now sees a *different* S' >> >> clock >> >> next to it as being fast (it shows 12:30 when B shows 12:00) >> >> >> If you look at the same scenario but from the point of view of the >> >> other >> >> row >> >> of clocks, you get symmetric results. >> >> >> This is how clock synch affects measured ticking rates for moving >> >> clocks >> >> in >> >> SR. Even though the clocks themselves do NOT change their intrinsic >> >> ticking >> >> rates.- Hide quoted text - >> >> > Looks good, but let's take it one step further. The observer with >> > clock A jumps to frame S" which is traveling in the same direction as >> > S relative to S' but at twice the velocity. >> >> > S" 1:00 12:00=A 11:00 -->2v >> > S' 11:30 12:00=A 12:30 <--v >> > S 12:30=C 12:00=B 11:30 -->v >> >> > Clocks A and B continue to tick at there same intrinsic ticking rate >> > and an hour later A has overtaken B. >> >> > S" 2:00 1:00=A 12:00 -->2v >> > S' 12:30 1:00=A 1:30 <--v >> > S 1:30=C 1:00=B 12:30 -->v >> >> > The above provides the same situation as the twins paradox. Clock A >> > left clock B and returned. So why doesn't clock A show less time >> > elapsed than B? (Note the clocks in S" are further out of sync than >> > those in S due to the higher velocity.) >> >> The three clock situation cannot be so easily drawn .. bit like trying to >> drawing a three dimensional figure in 2d :) This sort of diagram only >> really works for a single pair of clocks looking from a third frame in >> which >> they move with the same speed. Things are trickier when there is frame >> jumping going on :):)- Hide quoted text - >> >> - Show quoted text - > > The question still remains, if there is no change in the tick rate of > the clock, how can clock A have fewer ticks recorded when it is > brought back to clock B? Look at the Lorentz transforms to see. Its all due to clock synch.
From: Jerry on 8 Mar 2010 07:10
On Mar 7, 11:11 pm, "Inertial" <relativ...(a)rest.com> wrote: > "Jerry" <Cephalobus_alie...(a)comcast.net> wrote in message > > news:4618fc10-f129-4474-b8c4-3eb3466dc5ab(a)t41g2000yqt.googlegroups.com... > > > On Mar 7, 9:00 pm, "Inertial" <relativ...(a)rest.com> wrote: > > >> I agree .. the existence of an aether is not falsifiable. Unless perhaps > >> some GR predictions (say)would be incompatible with an aether (but > >> compatible with SR). I'm certainly not aware of any test that would > >> allow > >> one to test for its presence or not. > > > I beg to differ on the matter of falsifiability, at least in > > principle. > > OK .. so you know how to falsify the hypothesis that aether exists? > > > The classical luminiferous aether that we are most familiar with > > is a hypothetical medium that allows the transmission of > > electromagnetic disturbances through otherwise empty space. > > Hypothetical, but not (as yet) falsifiable > > > But > > there are other forces besides electromagnetic: There are the > > strong, weak, and gravitational forces. > > > These other forces are so completely different in properties from > > electromagnetic forces, that they -MUST- be transmitted via their > > own aethers. > > Why not the same aether? Why does there need to be ANY aethers? How does > this make the ( luminiferous ) aether falsifiable .. let alone the others > (if any) ? You forget that the WHOLE PURPOSE OF AN AETHER was to provide a mechanistic basis for the transmission of waves. Classically, supporters of the aether tied themselves into knots trying to come up with an aether with the necessary mechanical properties to support all the known characteristics of light. > > It is absurd to imagine that a single aether could > > be responsible for transmission of forces of such diverse > > characteristics. > > Why absurd? No more absurd than the notion of an aether for EMR? > > > Therefore, besides the luminiferous aether, > > there must exist strong, weak, and gravitational aethers. > > You simply assert that. There is no particular reason to do so. It is not > a prediction of LET. Read Lorentz's original writings. Here on these newsgroups we tend to forget that Lorentz was developing a theory of the electron. LET is not an abstract mathematical theory. It is a MECHANISTIC theory. > > These diverse aethers would be expected to differ from each other > > in their mechanical properties, > > What mechanical properties does aether have? That is what advocates of an aether must supply. > > and therefore the speed at which > > waves propagate through them must differ. > > Why? Why not? > > Likewise, these diverse aethers should couple with matter > > differently. In other words, there is no reason that a strong > > aether wind, weak aether wind, or gravitational aether wind > > should induce "length contraction" in the same way that a flowing > > luminiferous aether induces length contraction in material > > substances. > > Or even why it ANY aether should induce object compressions and process > slowing due to movement through it That is an INTRINSIC assumption of LET. > > ================================================================= > > A fundamental prediction of aether theories must therefore be > > that gravitational waves, electromagnetic waves, strong waves, > > and weak waves all propagate at different constant speeds. > > No .. that does not follow > > > For > > even two of these forces to share the same speed of transmission > > would constitute a coincidence so unlikely as to beggar the > > imagination. > > Not really. > > > Furthermore, only the luminiferous aether should be undetectable > > due to the length and time distortion effects otherwise known as > > the Lorentz transformations. > > We only need one aether to do that. That is enough to make all aethers (if > any) undetectable (if they have the same propagation speed). > > > The measured speed of transmission > > of the other forces should exhibit measurable anisotropies in > > different directions due to the Earth's motions through space. > > You are making your own assertions about what you think is the case > falsifiable. Your assumptions can be false and LET still valid. > > So we're back at square one. No. Because you are mistakenly treating LET as an abstract mathematical theory. It is not. > > ================================================================= > > Special relativity, however, makes a different prediction than > > aether theories. Electromagnetic waves, gravitational waves, and > > strong waves should all travel at a common speed c, while the > > weak force should not propagate at any constant speed. > > ================================================================= Jerry |