Simultaneity of Relativity
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From: Bruce Richmond on 9 Oct 2009 19:02 On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > On Oct 9, 8:53 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > > On Oct 9, 8:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Oct 8, 8:34 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > > > > > > > > > Sorry, I've fouled this up. > > > > > > > > > > > > > > What Einstein's gedanken says is that the light from A/A' and the > > > > > > > > > > > > > light from B/B' arrive simultaneously at M and NOT simultaneously at > > > > > > > > > > > > > M'. > > > > > > > > > > > > > > And if this were viewed from M', because the propagation toward M' is > > > > > > > > > > > > > c from either A/A' or B/B', then it would be clear that events at A > > > > > > > > > > > > > and B were not simultaneous. > > > > > > > > > > > > > > PD > > > > > > > > > > > > > OK, at least you now understand Relativity of Simultaneity. > > > > > > > > > > > > > In Simultaneity of Relativity, both frames are equal. > > > > > > > > > > > > That's all well and good, but experiment agrees with Einstein, not > > > > > > > > > > > with your picture. > > > > > > > > > > > How would you know? You just figured out what Relativity of > > > > > > > > > > Simultaneity is two minutes ago. > > > > > > > > > > :>) > > > > > > > > > Well, I certainly did have difficulty explaining it right at first. > > > > > > > > > > But the experimental stuff has been figured out a long time ago. > > > > > > > > > > > > > Consider the > > > > > > > > > > > > aether to be 'entrained' by the embankment in the embankment frame of > > > > > > > > > > > > reference and for the aether to be 'entrained' by the train in the > > > > > > > > > > > > train frame of reference. > > > > > > > > > > > > OK, but the train observer could well be sitting on top of the train > > > > > > > > > > > out in the open air, right along with the air that is surrounding the > > > > > > > > > > > embankment. > > > > > > > > > > > So unless you've got overlapping aethers, one passing through the > > > > > > > > > > > other, then there would have to be a boundary between the two moving > > > > > > > > > > > masses of aether, where they are rubbing up against each other. And in > > > > > > > > > > > that case, there would be a region of aether in between where it is > > > > > > > > > > > moving somewhat in between what the two entrained aethers are moving. > > > > > > > > > > > And then just by moving, say, the embankment observer a little closer > > > > > > > > > > > to the train, or the train observer a little to one side, then you'd > > > > > > > > > > > start seeing the effect of the aether moving at a speed somewhat in > > > > > > > > > > > between. However, this is not observed in equivalent experiments. > > > > > > > > > > > Post a link to the experiments you are referring to. > > > > > > > > > > Google "experimental basis for relativity" > > > > > > > > > If you say this is not observed in equivalent experiments, you should > > > > > > > > be willing and able to backup up such a statement with specifics. > > > > > > > > > But, since you just figured out what Relativity of Simultaneity is > > > > > > > > five minutes ago, its understandable you can't backup the claims you > > > > > > > > make. > > > > > > > > Such cheesy baiting. > > > > > > > If you actually do the search I recommended, and you click on the > > > > > > > FIRST link it returns, you'll have a lovely list of experiments. > > > > > > > If you cannot do even this without whining, is it an indicator that > > > > > > > you are hopelessly lazy or hopelessly incompetent? > > > > > > > > > > > > This is what I mean by following the implications of an idea all the > > > > > > > > > > > way through to look for *uniquely distinguishing* predictions. I've > > > > > > > > > > > just given an example of a clear implication of AD, one that would be > > > > > > > > > > > testable. And unfortunately, it doesn't match experiment. So it's > > > > > > > > > > > gotta be wrong. > > > > > > > > > > > Experiments like de Sitter and the double star? > > > > > > > > > > No. That has to do with something else entirely. > > > > > > > > > That has to do with a test that distinguishes ballistic emission > > > > > > > > > theory and relativity. > > > > > > > > > Nothing to do with simultaneity. > > > > > > > > > Simultaneity of Relativity is emission theory in an entrained aether. > > > > > > > > No, it's not. In your theory the speed of light is relative to the > > > > > > > aether. In ballistic theory it is relative to the source. > > > > > > > If the train is half full of water and the water is stationary in the > > > > > > train and you drop pebbles at A' and B', the waves from A' and B' will > > > > > > reach M' simultaneously. > > > > > > > If the embankment is half full of water and the water is stationary > > > > > > relative to the embankment and you drop pebbles into the water at A > > > > > > and B, the waves from A and B will reach M simultaneously. > > > > > > > If you drop pebbles into the water at A and A' simultaneously and drop > > > > > > pebbles into B and B' simultaneously, if the waves from A and B reach > > > > > > M simultaneously, the waves from A' and B' will reach M' > > > > > > simultaneously. > > > > > > If it helps, MPC, Einstein's train gedanken can just as well take > > > > > place on open, flat-bed cars. > > > > > The water is stationary relative to the embankment and the train is > > > > moving along under the water and not affecting the water. Pebbles are > > > > dropped at A/A' and B/B'. The wave from B/B' travels from B to M'. The > > > > waves from A and B and reach M simultaneously. The wave from A reaches > > > > M'. > > > > And notice that the waves from A and B do not arrive at M' at the same > > > time. > > > Yes, because the water is stationary relative to the embankment. In > > this scenario, the embankment is the preferred frame. > > > For Einstein's train thought experiment to be truly relative, there > > can be no preferred frame. > > > Therefore, the water must be stationary relative to the embankment in > > the embankment frame of reference and stationary relative to the train > > in the train reference frame. > > Yes! And notice that, because the train cars are open, flatbed cars, > you have to satisfy both criteria at the same time! > > Here's where the fun starts. So if there is an aether (or water as you > want to analogize), it has to be stationary with respect to the > embankment AND to the train, at the same time. Not different > scenarios. At the same time. > Why not use the LET interpertation for the same math. The aether/ water is not at rest with either the train or the embankment. But because of the method used to sync clocks in each frame they both measure the wave speed to be the same. > > > In this scenario, my animation holds in the light from A and B reaches > > M and the light from A' and B' reaches M' simultaneously. > > No, certainly not. Because it's the same medium. > The embankment observer notes that the light from A and B reaches M' > at different times. > The train observer has to agree with that. Nature doesn't produce two > different measurable outcomes at the same time. There is only one. > Either the light arrives at the same time at M' or it doesn't. The > embankment observer and the train observer have to agree which one of > those two it was. > > It appears that you are having a slow time getting a grip on what the > Einstein gedanken really says. > > > > > > > The water is stationary relative to the train. Pebbles are dropped at > > > > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B' > > > > reach M' simultaneously. The wave from B' reaches M. A and B are > > > > irrelevant in this scenario. > > > > OK, but there are really only two lightning strikes, and the water > > > doesn't really have time to switch from being stationary relative to > > > the embankment to being stationary relative to the train. > > > The water doesn't have to switch. The water is stationary relative to > > the embankment in the embankment frame of reference and the water is > > stationary relative to the train in the train frame of reference. > > But these aren't two different sequences of events. It's the same > train, the same two lightning strikes, and there is only one pool of > water surrounding the embankment and the open train cars. So you tell > me, how can the water be stationary relative to the train AND > stationary relative to the embankment? > > > > > There is a single lightning strike at A/A' but A in on the embankment > > and A' is on the train. Likewise with the lightning strike at B/B'. > > > > Einstein's gedanken is about ONE pair of events (the lightning > > > strikes) and what happens to the light as observed by M and M' for > > > that ONE case, not two cases. > > > That is why I am saying Einstein is incorrect. He is trying to have it > > both ways. He wants to have a single lightning strike in two reference > > frames where the reference frames are not equal. > > What do you mean "equal"? > > The same sequence of events live in a bunch of reference frames all at > once. > If a sailor falls from the crow's nest of a ship, you can look at that > sequence of events from the deck of the ship or you can look at that > SAME sequence of events from the shore. This is looking at the SAME > sequence of events from two different reference frames. > In the reference frame of the ship, the sailor falls in a straight > line down and lands at the bottom of the mast. In the reference frame > of the shore (because the ship is moving relative to the shore), the > sailor falls in a parabola, landing some distance to one side of where > he left the crow's nest. This is what Galileo understood and used as > an example to explain. > There is only one sailor and he only fell once. The sailor travels in > a straight line AND in a parabola AT THE SAME TIME. It's just that the > path is dependent on the reference frame. > > > > > If his train thought experiment was correct with equal reference > > frames, the light from the lightning strikes at A and B would reach M > > and the light from the lightning strikes at A' and B' would reach M' > > simultaneously: > > But they DON'T, in real life, as determined in experiment. > > > > > > >http://www.youtube.com/watch?v=jyWTaXMElUk > > > > > 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text -
From: Bruce Richmond on 9 Oct 2009 19:04 On Oct 9, 11:06 am, mpc755 <mpc...(a)gmail.com> wrote: > On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Oct 9, 8:53 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Oct 9, 8:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Oct 8, 8:34 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > > > > > > > > > > Sorry, I've fouled this up. > > > > > > > > > > > > > > > What Einstein's gedanken says is that the light from A/A' and the > > > > > > > > > > > > > > light from B/B' arrive simultaneously at M and NOT simultaneously at > > > > > > > > > > > > > > M'. > > > > > > > > > > > > > > > And if this were viewed from M', because the propagation toward M' is > > > > > > > > > > > > > > c from either A/A' or B/B', then it would be clear that events at A > > > > > > > > > > > > > > and B were not simultaneous. > > > > > > > > > > > > > > > PD > > > > > > > > > > > > > > OK, at least you now understand Relativity of Simultaneity. > > > > > > > > > > > > > > In Simultaneity of Relativity, both frames are equal. > > > > > > > > > > > > > That's all well and good, but experiment agrees with Einstein, not > > > > > > > > > > > > with your picture. > > > > > > > > > > > > How would you know? You just figured out what Relativity of > > > > > > > > > > > Simultaneity is two minutes ago. > > > > > > > > > > > :>) > > > > > > > > > > Well, I certainly did have difficulty explaining it right at first. > > > > > > > > > > > But the experimental stuff has been figured out a long time ago. > > > > > > > > > > > > > > Consider the > > > > > > > > > > > > > aether to be 'entrained' by the embankment in the embankment frame of > > > > > > > > > > > > > reference and for the aether to be 'entrained' by the train in the > > > > > > > > > > > > > train frame of reference. > > > > > > > > > > > > > OK, but the train observer could well be sitting on top of the train > > > > > > > > > > > > out in the open air, right along with the air that is surrounding the > > > > > > > > > > > > embankment. > > > > > > > > > > > > So unless you've got overlapping aethers, one passing through the > > > > > > > > > > > > other, then there would have to be a boundary between the two moving > > > > > > > > > > > > masses of aether, where they are rubbing up against each other. And in > > > > > > > > > > > > that case, there would be a region of aether in between where it is > > > > > > > > > > > > moving somewhat in between what the two entrained aethers are moving. > > > > > > > > > > > > And then just by moving, say, the embankment observer a little closer > > > > > > > > > > > > to the train, or the train observer a little to one side, then you'd > > > > > > > > > > > > start seeing the effect of the aether moving at a speed somewhat in > > > > > > > > > > > > between. However, this is not observed in equivalent experiments. > > > > > > > > > > > > Post a link to the experiments you are referring to. > > > > > > > > > > > Google "experimental basis for relativity" > > > > > > > > > > If you say this is not observed in equivalent experiments, you should > > > > > > > > > be willing and able to backup up such a statement with specifics. > > > > > > > > > > But, since you just figured out what Relativity of Simultaneity is > > > > > > > > > five minutes ago, its understandable you can't backup the claims you > > > > > > > > > make. > > > > > > > > > Such cheesy baiting. > > > > > > > > If you actually do the search I recommended, and you click on the > > > > > > > > FIRST link it returns, you'll have a lovely list of experiments. > > > > > > > > If you cannot do even this without whining, is it an indicator that > > > > > > > > you are hopelessly lazy or hopelessly incompetent? > > > > > > > > > > > > > This is what I mean by following the implications of an idea all the > > > > > > > > > > > > way through to look for *uniquely distinguishing* predictions. I've > > > > > > > > > > > > just given an example of a clear implication of AD, one that would be > > > > > > > > > > > > testable. And unfortunately, it doesn't match experiment. So it's > > > > > > > > > > > > gotta be wrong. > > > > > > > > > > > > Experiments like de Sitter and the double star? > > > > > > > > > > > No. That has to do with something else entirely. > > > > > > > > > > That has to do with a test that distinguishes ballistic emission > > > > > > > > > > theory and relativity. > > > > > > > > > > Nothing to do with simultaneity. > > > > > > > > > > Simultaneity of Relativity is emission theory in an entrained aether. > > > > > > > > > No, it's not. In your theory the speed of light is relative to the > > > > > > > > aether. In ballistic theory it is relative to the source. > > > > > > > > If the train is half full of water and the water is stationary in the > > > > > > > train and you drop pebbles at A' and B', the waves from A' and B' will > > > > > > > reach M' simultaneously. > > > > > > > > If the embankment is half full of water and the water is stationary > > > > > > > relative to the embankment and you drop pebbles into the water at A > > > > > > > and B, the waves from A and B will reach M simultaneously. > > > > > > > > If you drop pebbles into the water at A and A' simultaneously and drop > > > > > > > pebbles into B and B' simultaneously, if the waves from A and B reach > > > > > > > M simultaneously, the waves from A' and B' will reach M' > > > > > > > simultaneously. > > > > > > > If it helps, MPC, Einstein's train gedanken can just as well take > > > > > > place on open, flat-bed cars. > > > > > > The water is stationary relative to the embankment and the train is > > > > > moving along under the water and not affecting the water. Pebbles are > > > > > dropped at A/A' and B/B'. The wave from B/B' travels from B to M'.. The > > > > > waves from A and B and reach M simultaneously. The wave from A reaches > > > > > M'. > > > > > And notice that the waves from A and B do not arrive at M' at the same > > > > time. > > > > Yes, because the water is stationary relative to the embankment. In > > > this scenario, the embankment is the preferred frame. > > > > For Einstein's train thought experiment to be truly relative, there > > > can be no preferred frame. > > > > Therefore, the water must be stationary relative to the embankment in > > > the embankment frame of reference and stationary relative to the train > > > in the train reference frame. > > > Yes! And notice that, because the train cars are open, flatbed cars, > > you have to satisfy both criteria at the same time! > > > Here's where the fun starts. So if there is an aether (or water as you > > want to analogize), it has to be stationary with respect to the > > embankment AND to the train, at the same time. Not different > > scenarios. At the same time. > > > > In this scenario, my animation holds in the light from A and B reaches > > > M and the light from A' and B' reaches M' simultaneously. > > > No, certainly not. Because it's the same medium. > > The embankment observer notes that the light from A and B reaches M' > > at different times. > > Yes, the light from A and B reaches M' at different times, but the > light from A' and B' reaches M' simultaneously. There is only one wave front emitted at A/A' and one at B/B'. Your inimation is wrong. > > The train observer has to agree with that. > > Yes, the train observer agrees the light from A and B reaches him at > different times, but the light from A' and B' reaches him > simultaneously. > > > > > > > Nature doesn't produce two > > different measurable outcomes at the same time. There is only one. > > Either the light arrives at the same time at M' or it doesn't. The > > embankment observer and the train observer have to agree which one of > > those two it was. > > > It appears that you are having a slow time getting a grip on what the > > Einstein gedanken really says. > > > > > > The water is stationary relative to the train. Pebbles are dropped at > > > > > A/A' and B/B'. The wave from A' reaches M. The waves from A' and B' > > > > > reach M' simultaneously. The wave from B' reaches M. A and B are > > > > > irrelevant in this scenario. > > > > > OK, but there are really only two lightning strikes, and the water > > > > doesn't really have time to switch from being stationary relative to > > > > the embankment to being stationary relative to the train. > > > > The water doesn't have to switch. The water is stationary relative to > > > the embankment in the embankment frame of reference and the water is > > > stationary relative to the train in the train frame of reference. > > > But these aren't two different sequences of events. It's the same > > train, the same two lightning strikes, and there is only one pool of > > water surrounding the embankment and the open train cars. So you tell > > me, how can the water be stationary relative to the train AND > > stationary relative to the embankment? > > It's the same two lightning strikes, but it is occurring at A on the > embankment and A' on the train. > > You can have a bucket of water that is stationary on the embankment > and a bucket of water that is stationary on the train. > > > > > > > > There is a single lightning strike at A/A' but A in on the embankment > > > and A' is on the train. Likewise with the lightning strike at B/B'. > > > > > Einstein's gedanken is about ONE pair of events (the lightning > > > > strikes) and what happens to the light as observed by M and M' for > > > > that ONE case, not two cases. > > > > That is why I am saying Einstein is incorrect. He is trying to have it > > > both ways. He wants to have a single lightning strike in two reference > > > frames where the reference frames are not equal. > > > What do you mean "equal"? > > > The same sequence of events live in a bunch of reference frames all at > > once. > > If a sailor falls from the crow's nest of a ship, you can look at that > > sequence of events from the deck of the ship or you can look at that > > SAME sequence of events from the shore. This is looking at the SAME > > sequence of events from two different reference frames. > > In the reference frame of the ship, the sailor falls in a straight > > line down and lands at the bottom of the mast. In the reference frame > > of the shore (because the ship is moving relative to the shore), the > > sailor falls in a parabola, landing some distance to one side of where > > he left the crow's nest.- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text -- Hide quoted text - > > - Show quoted text -... > > read more »
From: Bruce Richmond on 9 Oct 2009 19:50 On Oct 9, 1:26 pm, mpc755 <mpc...(a)gmail.com> wrote: > On Oct 9, 1:17 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Oct 9, 12:08 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Oct 9, 12:30 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Oct 9, 10:06 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > On Oct 9, 8:53 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > > > On Oct 9, 8:57 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > On Oct 8, 8:34 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > > > > > > > > > > > > > > Sorry, I've fouled this up. > > > > > > Yes, the light from A and B reaches M' at different times, but the > > > > > light from A' and B' reaches M' simultaneously. > > > > > A and A' are a single strike. B and B' are a single strike. > > > > Yes, A and A' are a single strike but A and A' are two different > > > locations in three dimensional space. A in on the embankment and A' is > > > on the train. > > > No, they are not. You have not read the gedanken carefully. A lighting > > strike hits in ONE place, not two. A and A' are two labels for the > > same point. In the original gedanken, A and A' label the point where > > the train meets the track at one end of the train. That is ONE POINT. > > > Please reread it and pay more attention than what you have been doing > > so far. > > The lightning strike leaves marks at A, A', B, and B'. This is four > different locations in three dimensional space. A and A' and B and B' > were co-located at the time of the strikes, but they are four > different locations. > > If A and A' are two labels for the same point, why does the Observer > at M measure to A and B and the Observer at M' measure to A' and B'? > The measure to the appropriate marks because there are four marks. > > Please try and understand if you have four marks at four locations > that is four points. > The mark at A on the tracks and the mark at A' on the train were made when the two points were together. M considers the strike to have happen at A. There are scorch marks on the tracks marking the spot. There are also scorch marks on the train, but the train is moving relative to the tracks, so the marks on the train are not where the strike took place in the track frame. M' considers the strike to have happen at A'. There are scorch marks on the train marking the spot. There are also scorch marks on the tracks, but the tracks are moving relative to the train, so the marks on the tracks are not where the strike took place in the train frame. > > > > > The light from A/A' travels through the *same medium* that the > > > > embankment and the open flatbed train cars are immersed in. The light > > > > from B/B' does the same thing. > > > > So how does the light, coming from a single lightning strike (A/A'), > > > > traveling through a common medium, arrive at the same observer M' both > > > > simultaneously and not simultaneously as the light from B/B'? > > > > It doesn't. If the train contains open flatbed cars, then you are > > > implying the medium is stationary relative to the embankment. > > > No, I'm not. There's no such implication at all. What you know is true > > is that there is ONE medium, not two. > > If there is one medium that is stationary relative to one of the > frames of reference in Einstein's train thought experiment then that > means it is moving relative to the other frame of reference which > means there is a preferred frame of reference. > There is only one medium and it is not stationary relative to either frame, so neither one is preferred. [snip]
From: Inertial on 9 Oct 2009 19:55 "Bruce Richmond" <bsr3997(a)my-deja.com> wrote in message news:ed15034f-aa9e-482e-b657-c5733eb61e87(a)a21g2000yqc.googlegroups.com... > On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > Why not use the LET interpertation for the same math. The aether/ > water is not at rest with either the train or the embankment. But > because of the method used to sync clocks in each frame they both > measure the wave speed to be the same. And don't forget that, according to LET, movement through the aether makes *all* processes run slower, and *all* objects and distances (material and non-material) compress. In LET this is a physical change to the object itself (it gets truly compressed when speed in the aether increases, or expanded when speed in aether decreases) and a physical slowing of the processes (they run slower when speed in the aether increases, and faster when speed in the aether decreases).
From: Bruce Richmond on 9 Oct 2009 20:10
On Oct 9, 7:55 pm, "Inertial" <relativ...(a)rest.com> wrote: > "Bruce Richmond" <bsr3...(a)my-deja.com> wrote in message > > news:ed15034f-aa9e-482e-b657-c5733eb61e87(a)a21g2000yqc.googlegroups.com... > > > On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > > Why not use the LET interpertation for the same math. The aether/ > > water is not at rest with either the train or the embankment. But > > because of the method used to sync clocks in each frame they both > > measure the wave speed to be the same. > > And don't forget that, according to LET, movement through the aether makes > *all* processes run slower, and *all* objects and distances (material and > non-material) compress. In LET this is a physical change to the object > itself (it gets truly compressed when speed in the aether increases, or > expanded when speed in aether decreases) and a physical slowing of the > processes (they run slower when speed in the aether increases, and faster > when speed in the aether decreases). But the observer never detects that change because the measuring rod changes in the exact same way as the object being measured. The method of clock sync hides the differences in light speed and length contraction. |