Agreed, it has not yet been proven,
when M and M' are co-located, the lightning strikes A' and B' simultaneously.
Is everything else OK?
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Relative Velocity Measurement – Frame and photon
- Thread starter geistkiesel
- Start date
Agreed, it has not yet been proven,
when M and M' are co-located, the lightning strikes A' and B' simultaneously.
Is everything else OK?
Agreed, it has not yet been proven,
when M and M' are co-located, the lightning strikes A' and B' simultaneously.
That's not what I said, Jack.
Where are you placing A' and B'?
Are you placing them at a distance d/γ from M'?
Or are you placing A' at A when lightning strikes A, and B' at B when lightning strikes B?
You seem to think that they are equivalent, or that one implies the other.
That's not what I said, Jack.
Where are you placing A' and B'?
Are you placing them at a distance d/γ from M'?
Or are you placing A' at A when lightning strikes A, and B' at B when lightning strikes B?
You seem to think that they are equivalent, or that one implies the other.
Good questions.
I have said it over and over.
A' is d/γ from M' and so is B' is d/γ.
That is all.
Everything else must be proved.
Do you understand it yet?
Good questions.
I have said it over and over.
A' is d/γ from M' and so is B' is d/γ.
That is all.
Everything else must be proved.
Do you understand it yet?
Well, you began this scenario by saying:
"Now, assume there were M' observers co-located at B and A when the lightning strikes occurred at A and B and call them A' and B'."
So long as we're clear that this is not what you're doing, that you are instead simply placing A' and B' at a particular distance d/γ from M', then we're good to go.
We can agree that:
In the rest frame of M, two points A and B are each a distance d from M.
In the rest frame of M, M' moves past M at velocity v.
In the rest frame of M, when M' and M are co-located, lightning strikes at A and at B.
In the rest frame of M', two points A' and B' are each a distance d/γ from M'.
In the rest frame of M', when M and M' are co-located, A is co-located with A' and B is co-located with B'.
Well, you began this scenario by saying:
"Now, assume there were M' observers co-located at B and A when the lightning strikes occurred at A and B and call them A' and B'."
So long as we're clear that this is not what you're doing, that you are instead simply placing A' and B' at a particular distance d/γ from M', then we're good to go.
We can agree that:
In the rest frame of M, two points A and B are each a distance d from M.
In the rest frame of M, M' moves past M at velocity v.
In the rest frame of M, when M' and M are co-located, lightning strikes at A and at B.
In the rest frame of M', two points A' and B' are each a distance d/γ from M'.
In the rest frame of M', when M and M' are co-located, A is co-located with A' and B is co-located with B'.
Good.
Now the orginal experiment stateme when M and M' are co-located the lightning strikes A and b simultaneosly.
Now, the reductio ad absurdum argument is applied by assuming Einstein’s conclusion that M' sees the light from B prior to A from the view of M' as stationary.
To support Einstein’s conclusion that M' sees the light from B prior to A one of the following two possibilities must be true:
1. M' moves toward the lightning strike at B closing the distance for light to travel relative to the strike at A.
2. The strike at B occurs prior to the strike at A in the time coordinates of M'.
Possibility 1
Since M' is stationary, it is not moving. A, B and M are moving relative to M'. Sure, B closes the distance to M' as the light travels toward M' but this has nothing to do with the distance light traveled in the frame of M'. The distance light traveled would be measured from B' to M' which is the distance from the light emission point in the frame to the strike point in the coordinates of the frame. That distance is d/γ. The same logic applies to A' and M' where that distance is also d/γ. This logic is supported by length contraction under SR. In particular, if a moving rod is of length d and a stationary rod is of length d/γ, then from the view of the stationary frame, the two ends of the rods can be simultaneously co-located. Hence, possibility one is not viable when taking M' as stationary since B' and A' are equidistant from M and M' when they are co-located and the lightning strikes.
Possibility 2
Since, there are the observers B' and A' co-located at the lightning strikes at A and B, it is impossible there is any disagreement between the frames as to whether light is moving along the x-axis or not. Hence, for example, if B' claims lightning just struck, B will make the same claim as well. So, it cannot be claimed the lightning appears for one frame at some location while a co-located observer claims light is not at that location. Therefore, perhaps the time on the clock of B' will show an earlier time than the clock of A' for the light strike and this explains it. In other words, the light emitted from B' before it emitted from A'.
So, let tB' be the time of the lightning strike at B' and tA' be the time of the strike at A'. Therefore, tB' < tA'. By the experiment, B' is located a distance d/γ from M' at the time of the strike and is co-located with B. At that strike at B', as required by the experiment, M and M' are co-located. But, that also implies M moves a distance (tA' - tB')v between the two lightning strikes in the time of M' if they indeed occur at different times in the M' frame. Thus, when the strike at A/A' occurs, M has moved a distance (tA' - tB')v, hence, M and M' are no longer co-located at the time of the strike at A/A'. So, possibility 2 is not viable.
Therefore, using this simple argument, the stationary frame of M' will be struck by two simultaneous equidistant lightning strikes and M will be struck by the lightning from A prior to B.
Jack, this has not been proven. That was the whole point of the last half-dozen or so posts.Possibility 2
Since, there are the observers B' and A' co-located at the lightning strikes at A and B,
I am curious.
Have either of you (or, for that matter, anyone who has posted in this thread) actually read the literature which is the basis of this thread?
Einstein's exhilarating little book "Relativity". The chapter which expostulates the "Relativity of simultaneity". I think I remember that it is Chapter 9. But not to worry. It is a little book, and it will be no trouble for anyone to find their way to the Simultaneity part.
Who among you have carefully read it before I have asked you about it here?
Have either of you (or, for that matter, anyone who has posted in this thread) actually read the literature which is the basis of this thread?
Einstein's exhilarating little book "Relativity". The chapter which expostulates the "Relativity of simultaneity". I think I remember that it is Chapter 9. But not to worry. It is a little book, and it will be no trouble for anyone to find their way to the Simultaneity part.
Who among you have carefully read it before I have asked you about it here?
You don't appear to have read that literature, UooHoo.And, uhhhhh, when Einstein tells us, with a grin and a wink, that the light flashes start at the ends of the car at the same moment, but arrive upon the Rider's eye at different moments, do you tell us that that happens in any frame?
If you do, you will find that it says if the the flashes cross equal distances at equal speeds and arrive in the middle at different moments, that they must also start at different moments.
Uno Hoo, you've made it abundantly clear in other threads on relativity and even threads on something as simple as pi that you aren't well read. You have failed to understand special relativity and the fact you've got one book written decades ago doesn't make you 'well read'. Is that the only book you have? Is anything more than one short book too taxing for you?I am curious.
Have either of you (or, for that matter, anyone who has posted in this thread) actually read the literature which is the basis of this thread?
Einstein's exhilarating little book "Relativity". The chapter which expostulates the "Relativity of simultaneity". I think I remember that it is Chapter 9. But not to worry. It is a little book, and it will be no trouble for anyone to find their way to the Simultaneity part.
Who among you have carefully read it before I have asked you about it here?
While reading the original work by a scientist can be informing it is rarely the best way to learn something. In the decades since Einstein has died huge advances in relativity have been made (its 'Golden age' was the 1960s). Reading more up to date books gives you the benefit of all the people who have worked on it since then. Another example is Maxwell's work. His original method for writing down his EM equations was to do with quaternions and it wasn't until Tesla that they were reformulated into their more familiar form. And if you use differential forms you get even simpler expressions but much of that work wasn't done till the 20th century.
So before trying to come off like you're well read I suggest you first read more than one book and second you make sure you can actually do special relativity. Of course if you feel I'm not being truthful please provide a link to a post of yours where you show real working understanding of relativity. Not too much to ask, is it?
Jack, this has not been proven. That was the whole point of the last half-dozen or so posts.
“ Originally Posted by Jack_
Possibility 2
Since, there are the observers B' and A' co-located at the lightning strikes at A and B,
Sure I proved this.
I proved when M and M' co-locate, then A' co-locates with A and B' co-locates with B.
Oh, the original thought experiment said when M and M' co-locate, then A and B are hit simultaneuously.
But, when M and M' co-locate, also, A' co-locates with A and B' co-locates with B.
This is based on length contraction.
Your only argument against this is A sees lightning heading down the x-axis and A' is c-located with A but A' claims light is not heading down the x-axis from exactly the same spot A see it.
Is this your position?
You don't appear to have read that literature, UooHoo.
If you do, you will find that it says if the the flashes cross equal distances at equal speeds and arrive in the middle at different moments, that they must also start at different moments.
Uhhhh, no.
It actually says any stationary frame with simultaneous equidistant light emissions from some point, the light will reach that point simultaneously.
That is all it says.
Now, why didn't the original R of S consider M' stationary?
Einstein committed the fallacy of the preferred frame and claimed the SR logic of M absolutely applies to M'.
All this seems so simple.
We are now correcting his fallacy and considering M' stationary.
The results are devastating to SR.
We will find no choice but to conclude M' will be struck simultaneously from its view as stationary.
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Didn't your experience with me suggest to you that perhaps your understanding isn't as good as you might wish to believe. You were telling me it was categorical that there was a contradiction in SR from your setup and there wasn't. Now you're doing the same.The results are devastating to SR.
If you were combing the very edges of known physics, such as working on string theory or non-perturbative gauge theory then claims of 'devastating' a particular area of physics would be more likely to be true but you're talking about a theory which has at its foundation nothing more than Riemannian geometry and Lie theory. as well as it being so ingrained into physics via quantum field theory and GR that its impossible to do a physics degree without learning some special relativity and almost certainly it would cover the kinds of set ups you're talking about. Hence hundreds of thousands, perhaps millions, of people have worked through these kinds of problems again and again, in both hypothetical experiments and actual ones. And yet no one has come across this. And believe me if I or anyone in the physicist community that I know would LOVE to stick a fork in SR and prove it wrong because you'd instantly become the person who reshaped the entirety of physics. You'd be remembered for as long as civilisation endures. But the simple fact of the matter is you aren't going to manage it by trying to use Lorentz transformations. It's a 'closed system', its a mathematical coherent structure.
It's hard to grasp just how many ways the consistency of Lorentz transformations are described. Lorentz transformations are essentially the examination of the tangent space of Minkowski space-time. If they didn't combine consistently fibre bundles wouldn't be consistent and yet they are. By ignoring the underlying mathematical justification for this consistency and trying to construct some convoluted physical system you're confusing yourself. Making a physical system more convoluted makes following it more difficult and its pointless because its the same underlying structure in the mathematics.
Just use some worldline diagrams and how they transform under a Lorentz transformations. Doing a couple of examples for generic motion you'll see that you can't break causality.
I don't mean to be rude (too much) but you struggled with the whole sphere intersection problem, claiming the point of intersection was not on the x axis when the Lorentz contraction was parallel to that axis and that you couldn't reduce the system to 1 dimensional, which you could.
When I read something and think "How did they manage that?" and then try to do it myself and find I get a different answer, repeatedly, my first thought is always "It's me, not them" and I keep trying. Eventually I'll ask someone else or read bits of books and after that do I then begin to say "Its them, not me". If your claims were right then a contradiction would be engrained in to SR at its core and since quantum field theory and GR both contain SR then any test of them is a test of SR. Nothing has ever countered SR's predictions. This whole "Lightning striking A and B" stuff is very similar in structure to things like particle accelerators, where electromagnetic fields are varied to push the particles more. Further more physicists don't work always in the same frame to describe particle collisions, they can have one of the particles in its rest frame or could work in the centre of mass frame. If your claims were true then a contradiction would arise in such experiments as they'd do a Lorentz transformation to make the algebra easier and if this transformation is flawed the predictions made would be wrong. The fact we can use Lorentz transformations to examine things we then measure means we have some kind of external check. Perhaps someone did so a mistake in SR and its been there ever since. If so particle colliders should not behave as predicted. This is not the case. If you tried to describe them with Galilean transformations you'd find a problem because you get the wrong predictions.
From experiment we see that nature has a symmetry so close to that described by Lorentz transformations that they must be very very close to being consistent if not perfectly consistent.
You proved that for the M' rest frame. Not for the M rest frame.Sure I proved this.
I proved when M and M' co-locate, then A' co-locates with A and B' co-locates with B.
Yes, that's given in the M rest frame. You are trying to prove it for the M' rest frame.Oh, the original thought experiment said when M and M' co-locate, then A and B are hit simultaneuously.
So, try again:
Can you prove that the observers B' and A' are co-located at the lightning strikes at A and B?
Either frame of reference frame will do. If you can prove it in one, then the other follows.
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Right, so it concludes that if, in a stationary frame with equidistant light emissions from some point, the light does not reach that point simultaneously, then the emissions were not simultaneous.Uhhhh, no.
It actually says any stationary frame with simultaneous equidistant light emissions from some point, the light will reach that point simultaneously.
So that's the conclusion reached with M' stationary:
- Equidistant emissions.
- Light received non-simultaneously.
- Therefore, light emitted non-simultaneously.
Einstein doesn't completely spell this out, but we've already discussed the questionable suitability of the seminal author as a learning resource, and the logic seems clear enough anyway:
Hence the observer will see the beam of light emitted from B earlier than he will see that emitted from A. Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash B took place earlier than the lightning flash A.
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Didn't your experience with me suggest to you that perhaps your understanding isn't as good as you might wish to believe. You were telling me it was categorical that there was a contradiction in SR from your setup and there wasn't. Now you're doing the same.
If you were combing the very edges of known physics, such as working on string theory or non-perturbative gauge theory then claims of 'devastating' a particular area of physics would be more likely to be true but you're talking about a theory which has at its foundation nothing more than Riemannian geometry and Lie theory. as well as it being so ingrained into physics via quantum field theory and GR that its impossible to do a physics degree without learning some special relativity and almost certainly it would cover the kinds of set ups you're talking about. Hence hundreds of thousands, perhaps millions, of people have worked through these kinds of problems again and again, in both hypothetical experiments and actual ones. And yet no one has come across this. And believe me if I or anyone in the physicist community that I know would LOVE to stick a fork in SR and prove it wrong because you'd instantly become the person who reshaped the entirety of physics. You'd be remembered for as long as civilisation endures. But the simple fact of the matter is you aren't going to manage it by trying to use Lorentz transformations. It's a 'closed system', its a mathematical coherent structure.
It's hard to grasp just how many ways the consistency of Lorentz transformations are described. Lorentz transformations are essentially the examination of the tangent space of Minkowski space-time. If they didn't combine consistently fibre bundles wouldn't be consistent and yet they are. By ignoring the underlying mathematical justification for this consistency and trying to construct some convoluted physical system you're confusing yourself. Making a physical system more convoluted makes following it more difficult and its pointless because its the same underlying structure in the mathematics.
Just use some worldline diagrams and how they transform under a Lorentz transformations. Doing a couple of examples for generic motion you'll see that you can't break causality.
I don't mean to be rude (too much) but you struggled with the whole sphere intersection problem, claiming the point of intersection was not on the x axis when the Lorentz contraction was parallel to that axis and that you couldn't reduce the system to 1 dimensional, which you could.
When I read something and think "How did they manage that?" and then try to do it myself and find I get a different answer, repeatedly, my first thought is always "It's me, not them" and I keep trying. Eventually I'll ask someone else or read bits of books and after that do I then begin to say "Its them, not me". If your claims were right then a contradiction would be engrained in to SR at its core and since quantum field theory and GR both contain SR then any test of them is a test of SR. Nothing has ever countered SR's predictions. This whole "Lightning striking A and B" stuff is very similar in structure to things like particle accelerators, where electromagnetic fields are varied to push the particles more. Further more physicists don't work always in the same frame to describe particle collisions, they can have one of the particles in its rest frame or could work in the centre of mass frame. If your claims were true then a contradiction would arise in such experiments as they'd do a Lorentz transformation to make the algebra easier and if this transformation is flawed the predictions made would be wrong. The fact we can use Lorentz transformations to examine things we then measure means we have some kind of external check. Perhaps someone did so a mistake in SR and its been there ever since. If so particle colliders should not behave as predicted. This is not the case. If you tried to describe them with Galilean transformations you'd find a problem because you get the wrong predictions.
From experiment we see that nature has a symmetry so close to that described by Lorentz transformations that they must be very very close to being consistent if not perfectly consistent.
Let's start with this.
I don't mean to be rude (too much) but you struggled with the whole sphere intersection problem, claiming the point of intersection was not on the x axis when the Lorentz contraction was parallel to that axis and that you couldn't reduce the system to 1 dimensional, which you could.
The x point I came up with could not be on the x-axis because it exists between the origin of O and the origin of O'. Hence, if light emitted when O and O' are co-located, then that necessitates O' traqvels faster than light.
I thought I taught you this already.
Thus, this point is not within the domain of LT.
So, you are wrong on that point.
Further, I taught you with this point that it most be the case there exists multiple valid light emission points under SR.
You agreed and claimed an experiment needed to be performed to test this.
I then produced a proof, using this point, if more than one light emission point is confessed in SR, then Sr will measure 2 different light speeds.
That is where it is left.
This is the correct understanding of SR.
You proved that for the M' rest frame. Not for the M rest frame.
Yes, that's given in the M rest frame. You are trying to prove it for the M' rest frame.
So, try again:
Can you prove that the observers B' and A' are co-located at the lightning strikes at A and B?
Either frame of reference frame will do. If you can prove it in one, then the other follows.
OK, I am not trying to prove anything about M at rest.
I do not know how many times I must say, we are looking at M' stationary.
Either frame of reference frame will do. If you can prove it in one, then the other follows.
This is false.
Can you prove that the observers B' and A' are co-located at the lightning strikes at A and B?
Yes, I did. Look up above at the proof.
Further, I proved if M and M' are co-located, the A' and A are co-located and so are B ad B'.
Physics folks should be required to take a one year course in proof theory.
What is it you do not understand about the proof?
Jack, that's exactly what I said. Are you not reading my posts, or just not thinking? Where exactly did I suggest that you need to prove or are trying to prove anything about M at rest?OK, I am not trying to prove anything about M at rest.
Focus, Jack. Read what I write. Please?
You proved that for M' at rest when M and M' co-locate, then A' co-locates with A and B' co-locates with B.
You are trying to prove that for M' at rest when M and M' co-locate, then A and B are hit simultaneously.
You are assuming without proof that for M' at rest the observers B' and A' are co-located at the lightning strikes at A and B?
So again I ask:
Can you prove that for M' at rest the observers B' and A' are co-located at the lightning strikes at A and B?
The irony is getting thicker by the second.Physics folks should be required to take a one year course in proof theory.
Right, so it concludes that if, in a stationary frame with equidistant light emissions from some point, the light does not reach that point simultaneously, then the emissions were not simultaneous.
So that's the conclusion reached with M' stationary:
- Equidistant emissions.
- Light received non-simultaneously.
- Therefore, light emitted non-simultaneously.
Einstein doesn't completely spell this out, but we've already discussed the questionable suitability of the seminal author as a learning resource, and the logic seems clear enough anyway:
Hence the observer will see the beam of light emitted from B earlier than he will see that emitted from A. Observers who take the railway train as their reference-body must therefore come to the conclusion that the lightning flash B took place earlier than the lightning flash A.
I am aware, when M is stationary, this is the conclusion.
This though is called the preferred frame fallacy.
Einstein took M as stationaryand did not consider M' as stationary.
We are now look at that.
The master said this:
Now in reality (considered with reference to the railway embankment) he is hastening towards the beam of light coming from B, whilst he is riding on ahead of the beam of light coming from A. Hence the observer will see the beam of light emitted from B earlier than he will see that emitted from A.
http://www.bartleby.com/173/9.html
Can you see the preferred frame fallacy?
What an excellent Newtonian conclusion.
He is saying M' is never stationary and is in absolute motion I guess.
I will fill in the words to help you understand the fallacy.
Now in reality (considered with reference to the railway embankment)
He is saying the M frame is the only reality.
he is hastening towards the beam of light coming from B, whilst he is riding on ahead of the beam of light coming from A.
This is the correct conclusion only when M is stationary.
Note how M' is moving.
Hence the observer will see the beam of light emitted from B earlier than he will see that emitted from A.
Here he commits preferred frame fallacy and claims the conclusions of frame M under relativity are absolute. Why? Because in reality, as he says, M' is moving absolutely toward the light.
This is junk science. Who believes this logical fallacy?
Jack, what exactly makes you consider yourself qualified to teach AlphaNumeric anything about physics or maths?
Look at the other thread.
I demonstrated and taught him.
First, he could not refute the twins contradiction I constructed.
Then, he was taught, like you, SR is a theory of multiple light emission points.
Once he agreed with this, I taught him multiple light emission points necessitates light is measured at different speeds.