A constant speed of light in all reference frames? Surely you can't be serious.
in [Relativity]
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From: Paul Stowe on 7 Mar 2010 23:34 On Mar 7, 7:48 pm, "FrediFizzx" <fredifi...(a)hotmail.com> wrote: > "Inertial" <relativ...(a)rest.com> wrote in message > > news:4b945dcc$0$8789$c3e8da3(a)news.astraweb.com... > > > LET is as possibly valid as SR .. Neither is refuted experimentally. > > I just don't think it is the correct physical explanation. LET is not > > compatible AFAIK with GR .. so is a bit of a dead end .. and has the > > assumption of an undetectableaetherwith properties that don't make > > sense. > > http://www.ilja-schmelzer.de/papers/glet.pdf "A GENERALIZATION OF THE > LORENTZ ETHER TO GRAVITY > WITH GENERAL-RELATIVISTIC LIMIT" Hi Fred, This looks interesting... http://arxiv.org/ftp/physics/papers/0501/0501060.pdf Paul Stowe
From: Jerry on 7 Mar 2010 23:58 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. 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. 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. It is absurd to imagine that a single aether could be responsible for transmission of forces of such diverse characteristics. Therefore, besides the luminiferous aether, there must exist strong, weak, and gravitational aethers. These diverse aethers would be expected to differ from each other in their mechanical properties, and therefore the speed at which waves propagate through them must differ. 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. ================================================================= 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. For even two of these forces to share the same speed of transmission would constitute a coincidence so unlikely as to beggar the imagination. Furthermore, only the luminiferous aether should be undetectable due to the length and time distortion effects otherwise known as the Lorentz transformations. The measured speed of transmission of the other forces should exhibit measurable anisotropies in different directions due to the Earth's motions through space. ================================================================= 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
From: Inertial on 8 Mar 2010 00:11 "Jerry" <Cephalobus_alienus(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) ? > 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. > These diverse aethers would be expected to differ from each other > in their mechanical properties, What mechanical properties does aether have? > and therefore the speed at which > waves propagate through them must differ. Why? > 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 > ================================================================= > 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. > ================================================================= > 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
From: Bruce Richmond on 8 Mar 2010 00:44 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. 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'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. Bruce
From: Bruce Richmond on 8 Mar 2010 00:51
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 |