Simultaneity of Relativity
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From: mpc755 on 10 Oct 2009 11:41 On Oct 10, 9:52 am, PD <thedraperfam...(a)gmail.com> wrote: > On Oct 9, 10:25 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > > On Oct 9, 6:14 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > On Oct 8, 11:49 am, mpc755 <mpc...(a)gmail.com> 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 > > > > I think the end result of this discussion, MPC, is that you've never > > > understood what's being said in the Einstein train gedanken. > > > > At this point, it might have been effective for you to say, "I guess I > > > don't understand what Einstein was trying to say. Is there anyone that > > > is willing to walk through it with me to explain to me what it's > > > saying?" > > > > For some people this is emotionally difficult to do. One recourse for > > > such people is to pretend that they understand what they do not, and > > > to try to invent something they can at least call their own, because > > > they do understand what they invent for themselves. The problem is, > > > this has nothing to do with science, where the value of an idea is > > > determined by how nature really acts, not how intuitive it is in our > > > heads. > > > > The right steps are to ask the following: > > > 1. "What is this relativity theory, exactly, and what does it say?" > > > 2. "OK, now that I understand what it claims, what makes you think > > > it's right?" > > > 3. "If there are other claims that have been put forward that are > > > different, how do you know that any of those are not right?" > > > > PD > > > I understand exactly what is occurring in Einstein's Train Thought > > experiment. > > Not as Einstein explained it, no you don't. > > You understand the MPC Train Thought Experiment, which is something > completely different than the Einstein Train Thought Experiment. > > > > > Lightning strikes at A/A' and B/B' behave exactly like the waves of > > pebbles dropped into stationary pools of water on the train and > > stationary pools of water on the embankment. > > > If there are stationary pools on the train and on the embankment, the > > waves the pebbles create from A and B reaches M and the light from A' > > and B' reaches M' simultaneously. > > > If there are stationary pools on the train and on the embankment, the > > light waves from A and B reach M and the light wave from A' and B' > > reach M' simultaneously. > > See? That's the MPC Train Thought Experiment, not the Einstein one. It's the same thought experiment, but I am starting with pebbles in the stationary medium of water, moving to flashes of light in the stationary medium water, moving to flashes of light in the stationary medium of aether.
From: PD on 10 Oct 2009 11:46 On Oct 10, 10:38 am, mpc755 <mpc...(a)gmail.com> wrote: > On Oct 10, 9:50 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Oct 9, 10:27 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Oct 9, 7:04 pm, Bruce Richmond <bsr3...(a)my-deja.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: > > > > > > > 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. > > > > Why is everyone afraid to answer my thought experiment with pebbles > > > and the waves they create and stationary water on the train and > > > stationary water on the embankment? > > > > If pebbles are dropped simultaneously at A and A' and pebbles are > > > dropped simultaneously at B and B', if the waves from A and B reach M > > > simultaneously do the waves from A' and B' reach M' simultaneously? > > > Answer in what way? > > It doesn't pertain to the Einstein gedanken, which is done out in the > > open so that at best there is ONE medium. > > If Einstein's Train Thought Experiment was done 'out in the open' then > you are tying the stationary aether to one of the frames of reference, No, *I'm* not, you are. Einstein made no presumption that an aether was present at all. And in fact, I asked you how you can tell with the information given that there is an aether tied to *either* frame of reference. I explicitly asked you how you know that the aether isn't moving relative to *both* the embankment and the train. > which is a different thought experiment than the one Einstein > proposes. > > Asking, 'Answer in what way?' is hiding from answering the following > question: > > If pebbles are dropped into the water simultaneously at A and A' and > pebbles are dropped into the water simultaneously at B and B', if the > waves from A and B reach M simultaneously do the waves from A' and B' > reach M' simultaneously? Sorry, but now you're asking questions about the MPC train thought experiment, not the Einstein gedanken. I was interested when you were claiming this has something to do with Einstein's gedanken, but I'm not interested in a wholly different example involving two tanks of water and pebbles.
From: PD on 10 Oct 2009 11:48 On Oct 10, 10:41 am, mpc755 <mpc...(a)gmail.com> wrote: > On Oct 10, 9:52 am, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Oct 9, 10:25 pm, mpc755 <mpc...(a)gmail.com> wrote: > > > > On Oct 9, 6:14 pm, PD <thedraperfam...(a)gmail.com> wrote: > > > > > On Oct 8, 11:49 am, mpc755 <mpc...(a)gmail.com> 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 > > > > > I think the end result of this discussion, MPC, is that you've never > > > > understood what's being said in the Einstein train gedanken. > > > > > At this point, it might have been effective for you to say, "I guess I > > > > don't understand what Einstein was trying to say. Is there anyone that > > > > is willing to walk through it with me to explain to me what it's > > > > saying?" > > > > > For some people this is emotionally difficult to do. One recourse for > > > > such people is to pretend that they understand what they do not, and > > > > to try to invent something they can at least call their own, because > > > > they do understand what they invent for themselves. The problem is, > > > > this has nothing to do with science, where the value of an idea is > > > > determined by how nature really acts, not how intuitive it is in our > > > > heads. > > > > > The right steps are to ask the following: > > > > 1. "What is this relativity theory, exactly, and what does it say?" > > > > 2. "OK, now that I understand what it claims, what makes you think > > > > it's right?" > > > > 3. "If there are other claims that have been put forward that are > > > > different, how do you know that any of those are not right?" > > > > > PD > > > > I understand exactly what is occurring in Einstein's Train Thought > > > experiment. > > > Not as Einstein explained it, no you don't. > > > You understand the MPC Train Thought Experiment, which is something > > completely different than the Einstein Train Thought Experiment. > > > > Lightning strikes at A/A' and B/B' behave exactly like the waves of > > > pebbles dropped into stationary pools of water on the train and > > > stationary pools of water on the embankment. > > > > If there are stationary pools on the train and on the embankment, the > > > waves the pebbles create from A and B reaches M and the light from A' > > > and B' reaches M' simultaneously. > > > > If there are stationary pools on the train and on the embankment, the > > > light waves from A and B reach M and the light wave from A' and B' > > > reach M' simultaneously. > > > See? That's the MPC Train Thought Experiment, not the Einstein one. > > It's the same thought experiment, but I am starting with pebbles in > the stationary medium of water, moving to flashes of light in the > stationary medium water, moving to flashes of light in the stationary > medium of aether. But here's the problem. You have not addressed what happens in the transition region between the two relatively moving bodies of water. You have also made a prediction of what will be observed in terms of arrival times at M and M' that is in conflict with experiment. So since you have these two problems that are not resolved, I see no reason to bang on your model further. Do you?
From: mpc755 on 10 Oct 2009 11:48 On Oct 10, 10:48 am, glird <gl...(a)aol.com> wrote: > On Oct 10, 9:52 am, PD wrote: > > > mpc755 wrote: > > > I understand exactly what is > > > occurring in Einstein's Train > > > Thought experiment. > > > Not as Einstein explained it, no you > don't. > > > You understand the MPC Train Thought > > Experiment, which is something > > completely different than the > > Einstein Train Thought Experiment. > > Yes. > > > << Lightning strikes at A/A' and B/B' behave exactly like the waves of > > pebbles dropped into stationary pools of water on the train and > stationary pools of water on the embankment. > If there are stationary pools on the train and on the embankment, the > waves the pebbles create from A and B reaches M and the light from A' > and B' reaches M' simultaneously. > If there are stationary pools on the train and on the embankment, the > light waves from A and B reach M and the light wave from A' and B' > reach M' simultaneously. >> > > > > > See? That's the MPC Train Thought > > Experiment, not the Einstein one. > > PD is right. In Einstein's, A and A' coincide when a given ray hits > point AA', and B and B' coincide when ray 2 hits BB'. In MPC's, A and > A' are different points than each other in 3-d space and so are b and > B'. > In Einstein, the space between AA' and BB' is empty and light moves > at c wrt to it while the train - thus points A', B' and midpoint M' - > moves to the right at v. in mpc, a luminiferous aether is trapped > within the moving train and is therefore moving wrt to the outside > aether taken as at rest wrt the embankment. > Therefore, as PD said, mpc's conclusions are unrelated to > Einstein's. > > BTW, this gedanken experiment by Einstein is to the layman, and > doesn't explain why simultaneity is relative to the states of motion > of different observers' clocks. > > glird > > them ir point It makes no difference if the points A and A' coincide side-by-side or not in Einstein's Train Thought Experiment. Saying it makes a difference shows your limited understanding of the Einstein's Train Thought Experiment. The only thing that matters in Einstein's Train Thought Experiment is the flash at A/A' occurring in a single instant and the flash of light at B/B' occurring in a single instant and for A and B to be equi- distant from M and for A' and B' to be equi-distant from M' and for the distance from A to M and B to M to be the same as the distance from A' to M' and B' to M'. Let me ask you about Einstein's Train Thought Experiment with the following variation. As described in the above sentence, if there is are simultaneous lightning strikes at A and A' and there are simultaneous lightning strikes at B and B', if the light from A and B reaches M simultaneously does the light from A' and B' reach M' simultaneously? And in terms of simultaneous, I am referring to any frame of reference. In other words, from the perspective of an observer on the embankment, if the light from A and B reaches the observer at M simultaneously, does the light from the lightning strikes at A' and B' reach M' simultaneously?
From: mpc755 on 10 Oct 2009 11:51
On Oct 10, 11:46 am, PD <thedraperfam...(a)gmail.com> wrote: > On Oct 10, 10:38 am, mpc755 <mpc...(a)gmail.com> wrote: > > > > > > If pebbles are dropped simultaneously at A and A' and pebbles are > > > > dropped simultaneously at B and B', if the waves from A and B reach M > > > > simultaneously do the waves from A' and B' reach M' simultaneously? > > > > Answer in what way? > > > It doesn't pertain to the Einstein gedanken, which is done out in the > > > open so that at best there is ONE medium. > > > If Einstein's Train Thought Experiment was done 'out in the open' then > > you are tying the stationary aether to one of the frames of reference, > > No, *I'm* not, you are. Einstein made no presumption that an aether > was present at all. > And in fact, I asked you how you can tell with the information given > that there is an aether tied to *either* frame of reference. I > explicitly asked you how you know that the aether isn't moving > relative to *both* the embankment and the train. > > > which is a different thought experiment than the one Einstein > > proposes. > > > Asking, 'Answer in what way?' is hiding from answering the following > > question: > > > If pebbles are dropped into the water simultaneously at A and A' and > > pebbles are dropped into the water simultaneously at B and B', if the > > waves from A and B reach M simultaneously do the waves from A' and B' > > reach M' simultaneously? > > Sorry, but now you're asking questions about the MPC train thought > experiment, not the Einstein gedanken. > I was interested when you were claiming this has something to do with > Einstein's gedanken, but I'm not interested in a wholly different > example involving two tanks of water and pebbles. If pebbles are dropped into the water simultaneously at A and A' and pebbles are dropped into the water simultaneously at B and B', if the waves from A and B reach M simultaneously do the waves from A' and B' reach M' simultaneously? |