Simultaneity of Relativity
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From: mpc755 on 9 Oct 2009 11:46 On Oct 9, 11:10 am, glird <gl...(a)aol.com> wrote: > On Oct 8, 12:49 pm, mpc755 wrote: > > < If the aether is stationary relative to the > embankment and stationary relative to the train, this is what will > occur in Einstein's train thought experiment: > http://www.youtube.com/watch?v=jyWTaXMElUk > > > Your illustration doesn't fit the above conditions, which require > the train to be stationary wrt the embankment. (In the demo, the train > - and its aether - are moving wrt to the track and its aether. Since > there is only one material medium in otherwise empty space, the demo > contradicts reality.) > > glird Why must the train be stationary wrt the embankment? If you are implying the aether is stationary relative to the embankment and not stationary relative to the train, then you are making the embankment the preferred frame. If that is the case, then the lightning strikes at A' and B' on the train are irrelevant and the light from B will reach M' prior to the light from A in all frames of reference. That is not what Einstein is implying. Einstein is implying the embankment frame of reference and the train frame of reference are equal in all respects. This means, however the aether exists in the embankment frame of reference it must also exist the same way in the train frame of reference. This means if the aether is stationary relative to the embankment in the embankment frame of reference than the aether must also be stationary relative to the train in the train frame of reference. There is only one material medium in otherwise empty space, but you are placing unnecessary and incorrect assumptions on it to think it cannot behave as all other mediums do. Any medium on the train moves with the train. Aether is no different.
From: mpc755 on 9 Oct 2009 12:01 On Oct 9, 11:06 am, mpc755 <mpc...(a)gmail.com> wrote: > On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > > > > > Sorry, I've fouled this up. > > > > > 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. > > > 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. > I missed where you say it is an open train car. If it is an open train car, which implies the water is stationary relative to the embankment and not stationary relative to the train, then the light from the lightning strike at A and B will not reach the observer at M' simultaneously and neither will the light from the lightning strikes at A' and B'. If the water is stationary relative to the embankment, the light from the lightning strike at B' will travel from B to M' and arrive prior to the light from the lightning strike at A' and will travel from A to M'. A' and B' are irrelevant if we are discussing 'open train cars' which implies the water is stationary relative to the embankment. You can replace 'water' with 'aether' in the above paragraph and the same outcome will occur. > > > > > 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. > > I think we can agree on the following: > > Pebbles are dropped at A, A', B, and B' simultaneously as determined > by observers. The water on the embankment is stationary relative to > the embankment in the embankment frame of reference. The water on the > train is stationary relative to the train in the train frame of > reference. > > If the waves from A and B reach M simultaneously, then the waves from > A' and B' reach M' simultaneously. The waves from A and B reach M and > the waves from A' and B' reach M' at the same time. > > If instead of pebbles being dropped into the water, we now have > flashes occur at A, A', B, and B' simultaneously as determined by > observers, then due to the results of experiments with water and light > performed by Fizeau and others, then if the light from A and B reaches > M simultaneously then the light from A' and B' reaches M' > simultaneously and the light from A and B reaches M and the light from > A' and B' reaches M' at the same time. > > Now, instead of water being stationary relative to the embankment in > the embankment frame of reference and water being stationary relative > to the train in the train frame of reference, we have aether > stationary relative to the embankment in the embankment frame of > reference and aether stationary relative to the train in the train > frame of reference, the results for simultaneously flashes of light at > A, A', B, and B' will be the same in aether as described above for > flashes in water. > > > >http://www.youtube.com/watch?v=jyWTaXMElUk > > > > > > 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment > >
From: PD on 9 Oct 2009 12:30 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. > > > > > > > > > > > > > > > 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. A and A' are a single strike. B and B' are a single strike. 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'? The observer M' either sees the flashes from the strikes at his eyes at the same time or he doesn't. He can't do both. > > > 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. A and A' are ONE lightning strike. B and B' are ONE lightning strike. Let's say that the ONE lightning strike at A/A' is greenish, and the lightning strike at B/B' is yellowish. The question is simple. There is a guy M' who is going to see the two lightning flashes. Does he see the yellowish and greenish ones at the same time or at different times? There can only be one answer, as this is something that the guy can write down when it happens. > > > 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. So? > > You can have a bucket of water that is stationary on the embankment > and a bucket of water that is stationary on the train. Same body of water that the train is immersed in and the embankment is immersed in. If it's not the same body of water, then there has to be a boundary between the two bodies of water. Where is that boundary? > > > > > > 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. > > I think we can agree on the following: > > Pebbles are dropped at A, A', B, and B' simultaneously as determined > by observers. That's just it. Whether they are simultaneous or not depends on the signals they actually receive at their locations. That is, the observers M and M' are not AT the locations A, A', B, B'. They are at the places marked M and M'. What they know is what happens where they are, and THAT tells them what happens at A, A', B, and B'. They have no other way of knowing. > The water on the embankment is stationary relative to > the embankment in the embankment frame of reference. The water on the > train is stationary relative to the train in the train frame of > reference. > > If the waves from A and B reach M simultaneously, then the waves from > A' and B' reach M' simultaneously. The waves from A and B reach M and > the waves from A' and B' reach M' at the same time. > > If instead of pebbles being dropped into the water, we now have > flashes occur at A, A', B, and B' simultaneously as determined by > observers, then due to the results of experiments with water and light > performed by Fizeau and others, then if the light from A and B reaches > M simultaneously then the light from A' and B' reaches M' > simultaneously and the light from A and B reaches M and the light from > A' and B' reaches M' at the same time. > > Now, instead of water being stationary relative to the embankment in > the embankment frame of reference and water being stationary relative > to the train in the train frame of reference, we have aether > stationary relative to the embankment in the embankment frame of > reference and aether stationary relative to the train in the train > frame of reference, the results for simultaneously flashes of light at > A, A', B, and B' will be the same in aether as described above for > flashes in water. > > > >http://www.youtube.com/watch?v=jyWTaXMElUk > > > > > > 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment > >
From: PD on 9 Oct 2009 12:35 On Oct 9, 11:01 am, mpc755 <mpc...(a)gmail.com> wrote: > On Oct 9, 11:06 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > > > > > > Sorry, I've fouled this up. > > > > > 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. > > > > 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. > > I missed where you say it is an open train car. If it is an open train > car, which implies the water is stationary relative to the embankment > and not stationary relative to the train, Well, hold on a second. Why isn't it possible the water is stationary relative to the train and not stationary relative to the embankment? > then the light from the > lightning strike at A and B will not reach the observer at M' > simultaneously and neither will the light from the lightning strikes > at A' and B'. Right. But the observer M' then says the following: "OK, I know the following things: 1. The strikes happened at distances that are equally apart from me. 2. The speed of the signal from those two places traveling to me is the same in both cases. 3. The signals did not arrive at the same time." From these bits of information it is OBVIOUS that the strikes originally happened at different times, because the time of propagation of the signal from the strikes to where the observer is standing is identical. If the time of propagation is the same, and they arrived at different times, then they started at different times. No escaping that conclusion. > If the water is stationary relative to the embankment, > the light from the lightning strike at B' will travel from B to M' and > arrive prior to the light from the lightning strike at A' and will > travel from A to M'. A' and B' are irrelevant if we are discussing > 'open train cars' which implies the water is stationary relative to > the embankment. > > You can replace 'water' with 'aether' in the above paragraph and the > same outcome will occur. > > > > > > > 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. > > > I think we can agree on the following: > > > Pebbles are dropped at A, A', B, and B' simultaneously as determined > > by observers. The water on the embankment is stationary relative to > > the embankment in the embankment frame of reference. The water on the > > train is stationary relative to the train in the train frame of > > reference. > > > If the waves from A and B reach M simultaneously, then the waves from > > A' and B' reach M' simultaneously. The waves from A and B reach M and > > the waves from A' and B' reach M' at the same time. > > > If instead of pebbles being dropped into the water, we now have > > flashes occur at A, A', B, and B' simultaneously as determined by > > observers, then due to the results of experiments with water and light > > performed by Fizeau and others, then if the light from A and B reaches > > M simultaneously then the light from A' and B' reaches M' > > simultaneously and the light from A and B reaches M and the light from > > A' and B' reaches M' at the same time. > > > Now, instead of water being stationary relative to the embankment in > > the embankment frame of reference and water being stationary relative > > to the train in the train frame of reference, we have aether > > stationary relative to the embankment in the embankment frame of > > reference and aether stationary relative to the train in the train > > frame of reference, the results for simultaneously flashes of light at > > A, A', B, and B' will be the same in aether as described above for > > flashes in water. > > > > >http://www.youtube.com/watch?v=jyWTaXMElUk > > > > > > > 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment > >
From: mpc755 on 9 Oct 2009 12:54
On Oct 9, 12:35 pm, PD <thedraperfam...(a)gmail.com> wrote: > On Oct 9, 11:01 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > On Oct 9, 11:06 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Oct 9, 10:52 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > > > > > > > > > > > > > Sorry, I've fouled this up. > > > > I missed where you say it is an open train car. If it is an open train > > car, which implies the water is stationary relative to the embankment > > and not stationary relative to the train, > > Well, hold on a second. Why isn't it possible the water is stationary > relative to the train and not stationary relative to the embankment? > The water could be stationary relative to the train and not stationary relative to the embankment. In that case, the light from the lightning strike at B/B' will travel from B' to M and the light from the lightning strike at A/A' will travel from A' to M. The light from A' and B' will reach M' simultaneously. If the water is stationary relative to the train and not stationary relative to the embankment, the lightning strikes at A and B are irrelevant in terms of where the light travels from. > > then the light from the > > lightning strike at A and B will not reach the observer at M' > > simultaneously and neither will the light from the lightning strikes > > at A' and B'. > > Right. > > But the observer M' then says the following: > "OK, I know the following things: > 1. The strikes happened at distances that are equally apart from me. > 2. The speed of the signal from those two places traveling to me is > the same in both cases. > 3. The signals did not arrive at the same time." > From these bits of information it is OBVIOUS that the strikes > originally happened at different times, because the time of > propagation of the signal from the strikes to where the observer is > standing is identical. If the time of propagation is the same, and > they arrived at different times, then they started at different times. > No escaping that conclusion. It sounds as if we are back discussing the water being stationary relative to the embankment. If that is the case then the observer at M' will not conclude the light traveled from A' and B' to reach him. If he does so, then he is incorrect. If the water is stationary relative to the embankment the Observer at M' will correctly conclude the light from the lightning strike at A/A' traveled from A and the light from the lightning strike at B/B' traveled from B. > > > If the water is stationary relative to the embankment, > > the light from the lightning strike at B' will travel from B to M' and > > arrive prior to the light from the lightning strike at A' and will > > travel from A to M'. A' and B' are irrelevant if we are discussing > > 'open train cars' which implies the water is stationary relative to > > the embankment. > > > You can replace 'water' with 'aether' in the above paragraph and the > > same outcome will occur. > > > > > > 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. > > > > I think we can agree on the following: > > > > Pebbles are dropped at A, A', B, and B' simultaneously as determined > > > by observers. The water on the embankment is stationary relative to > > > the embankment in the embankment frame of reference. The water on the > > > train is stationary relative to the train in the train frame of > > > reference. > > > > If the waves from A and B reach M simultaneously, then the waves from > > > A' and B' reach M' simultaneously. The waves from A and B reach M and > > > the waves from A' and B' reach M' at the same time. > > > > If instead of pebbles being dropped into the water, we now have > > > flashes occur at A, A', B, and B' simultaneously as determined by > > > observers, then due to the results of experiments with water and light > > > performed by Fizeau and others, then if the light from A and B reaches > > > M simultaneously then the light from A' and B' reaches M' > > > simultaneously and the light from A and B reaches M and the light from > > > A' and B' reaches M' at the same time. > > > > Now, instead of water being stationary relative to the embankment in > > > the embankment frame of reference and water being stationary relative > > > to the train in the train frame of reference, we have aether > > > stationary relative to the embankment in the embankment frame of > > > reference and aether stationary relative to the train in the train > > > frame of reference, the results for simultaneously flashes of light at > > > A, A', B, and B' will be the same in aether as described above for > > > flashes in water. > > > > > >http://www.youtube.com/watch?v=jyWTaXMElUk > > > > > > > > 'Fizeau experiment'http://en.wikipedia.org/wiki/Fizeau_experiment > > |