# Two lightning bolts striking either end of train

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But in any case that video proves that Einstein's law of simultaneity is wrong.

U will notice that initially he is standing at O1 a little over L/2 from the train (train length = L). Later he is standing at O2 a little less than L/2 from the train. The video says that in both cases he sees simultaneous flashes (they don't show O1 & O2, they are my invention)(& they don't actually refer to the two cases). They are correct, if he is standing still. But, he must have walked or run or jumped from O1 to O2, probably during the critical instant. In any case (3 cases in all), whether at O1 or at O2 or jumping in between (call this O12), he unquestionably (i think) sees simultaneous flashes.

Pathetic.

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It doesn't answer how the train observer has to reason. From the point of view of the train observer he (the train observer) DOES NOT move towards the beam of light. I.o.w. your <<Now in reality (considered with .... etc >> is not a reality for the train observer. He cannot use that.

That's not the point. (Also, it's not "my" quote - it's from Einstein, see my link to Bartleby (or provide your own alternate).)

The reasoning of the train observer is simply that they were physically between the two events but didn't see them at the same time. Thus, the events were not simultaneous.

We know (we, reading the thought experiment are neither the train nor embankment observer) that they didn't see them at the same time, as we've used the embankment observers view, which shows the flashes would reach the train observer at different times.

Yes, the train observer does not consider themselves to be moving (towards or away from flashes) - all they know is: they didn't see the (equidistant) flashes at the same time.

That's the problem with focussing on location. People might think M1 moves from the midpoint towards (the location of) the first flash. It doesn't. The train observer doesn't consider himself moving toward the front beam, nor flash location.

Yes, M' doesn't consider themselves as moving (I've made that clear each time, see point 1 post #18, so I don't know who would be confused), but M does see M' moving - and the original thought experiment from Einstein uses this to show the flashes would reach them at different times.

It's not silly, because you also have to refer to what the embankment observer experiences if both events occur simultaneously for the embankment observer. If you don't, why would you need an embankment observer in the thought experiment?

True, the embankment observer is "needed" here, to provide (a) proof the strikes were simultaneous in the embankment frame and (b) proof that the train observer couldn't see the flashes at the same time; but from the train observers point of view, all they know is that the flashes reach them at different times. They don't care about the embankment observer.

You are adding post-hoc analysis to the train observer that isn't needed.

If I read you correctly you would simply state: there are two events at same distance from an observer, the beams do not reach observers simultaneously, hence events didn't happen simultaneously for him.

From the train observers point of view, yes.

The whole purpose of the experiment is to find out whether the events occur simultaneously when both observers are together.

You're focusing on the wrong thing. The experiment actually stipulates that they are "together" when the events occur (according to the embankment observer) ...

Just when the flashes 1 of lightning occur, this point M' naturally coincides with the point M, ...

... then examines if both would conclude that the events were simultaneous, when they've seen the events.

Since seeing the events (with light speed not being instant) has to occur after that, M' couldn't still be together with M at that time - unless in the trivial case where the train isn't moving relative to the embankment.

Your interpretation is frankly weird.

From the train observer's perspective he (train observber) does not move toward the front beam, nor to location of flash.Hence what is left for the train oberver to know whether the events did happen simultaneously or not? All train obsever can think of is: <<IF both flash events also occur simultaneously for me when I and embankment observer are together, then both lightbeams should also reach me simultaneously. But I experiences they don't reach me simultaneously, hence flash events didn't happen simultaneously for me.>>

No. The train observer doesn't need the embankment observer to determine for themselves if the events were simultaneous.

I think you're falling into the trap of thinking the embankment observer is "special" (perhaps partly due to the setup giving them the simultaneous strikes, partly because they are on land and the train by "common sense" (which is wrong) being the thing that's moving) so trying too hard to explain everything by reference to that embankment observer.

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pzkpfw.

Thanks for the reply, However i dont see any need to change any word of what i wrote.

Re the lady in the train, i didn't reverse my opinion. When the observers in the ferris wheel are getting their moneys worth she is in the train going perpendicularly to the wheel, & hencely the strikes are not simultaneous for her (in the context of the experiment).

Re my posting#17, there i am referring to the mirror-image experiment, with train at rest & earth moving.

If one (or more than one) case contradicts a law then that law is wrong. Einstein's wording of his law is wrong, its too simplistic.

If i had to reword Einstein's law then i would make sure that it said that, when an observer sees an event, other observers moving relative to that observer will deduce a different time for the event compared to the time deduced by that observer. Finding a good wording for this will be very difficult. And if necessary i should include some extra wordage to describe any exceptions, eg if the relative motion is along some plane of symmetry of some sort.

And no, it isn't clear what is going on. I had trouble trying to understand what in hell Einstein was trying to say. The experiment is confusing enough as it is. Einstein's wording is not just sloppy, it is wrong. Einstein should never confuse the lightning strike (the time of the event) with the lightning flash (the time the event is observed).

And, Einstein should make a distinction between what an observer sees (ie when he/she sees it)(ie the flash) & what an observer deduces (ie the time of the strike). So here we have another layer of confusion.

And re science, u are wrong. Einsteinism is wrong 99% of the time. It is a religion, kept alive by censorship, bullying, misinformation & propaganda.

Name any instance of Einstein being correct & i will refer u the real facts. Obviously not on this thread, unless it refers to simultaneity (or trains).

VandD.

Do u agree with my ferris-wheel thought experiment????

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I think you're falling into the trap of thinking the embankment observer is "special"

Never.

(perhaps partly due to the setup giving them the simultaneous strikes,

I said that if the events also occur simultaneously for the train observer, then ...etc.

Read my lips: I said if...

I never said they actually do.

partly because they are on land and the train by "common sense" (which is wrong) being the thing that's moving) so trying too hard to explain everything by reference to that embankment observer.

I don't see where you get this. See my post 21: The train observer says:

<< IF both flashes also occur simultaneously for me when (at the moment in time) I meet the platform observer, THEN both light beams HAVE TO reach me simultaneously. But.... the lights from the bolts DO NOT reach me simultanously, hence the two events DID NOT occur simultaneously for me.>>

Maybe I had better said: <<If both flashes WOULD also occur simultaneously for me ... >> ? Sorry, english is my third language....

Edited by VandD
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And re science, u are wrong. Einsteinism is wrong 99% of the time. It is a religion, kept alive by censorship, bullying, misinformation & propaganda.

Name any instance of Einstein being correct & i will refer u the real facts. Obviously not on this thread, unless it refers to simultaneity (or trains).

And another -1. When will you stop posting rubbish?

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If one (or more than one) case contradicts a law then that law is wrong. Einstein's wording of his law is wrong, its too simplistic.

Too simplistic?

And no, it isn't clear what is going on. I had trouble trying to understand what in hell Einstein was trying to say.

And yet you still struggle to understand it?

I think it is pretty clear. Although there are better descriptions; I have only had to read Einstein's description because persistent crackpots insist on deliberately misinterpreting it in order to support their beliefs.

The video that was posted at the beginning of the thread presents it very clearly (from what I remember: I haven't watched it again, but I have recommended it in the past for people who struggle with this idea).

The experiment is confusing enough as it is. Einstein's wording is not just sloppy, it is wrong. Einstein should never confuse the lightning strike (the time of the event) with the lightning flash (the time the event is observed).

I don't think he does. The whole point of the thought experiment is to show that those are different things and that different people will experience the "flashes" differently and hence reach different conclusions about the "strikes".

There are really only two reasons for someone not being able to follow this very simple argument:

1. They are so emotionally attached to their delusional belief system that they invent errors and misinterpret what they read in order not to have to change their views.

2. They are extremely stupid.

And re science, u are wrong. Einsteinism is wrong 99% of the time.

So, for all of the experiments that are consistent with the predictions of relativity, there are 100 times as many that produce contradictory results? In which case you should easily be able to cite a few peer-reviewed scientific papers supporting this...

It is a religion, kept alive by censorship, bullying, misinformation & propaganda.

Please provide some evidence of this.

(Not holding my breath.)

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Strange.

Too simplistic for two reasons. The law should acknowledge that it doesn't apply if observers are moving in the plane of symmetry splitting the events. And anyhow it should be worded in some other way -- i suggest that it should say that the clock in an observer's frame will not give the same time (for the event) compared to another observer's clock (this observer moving relative to the first).

Re SR being correct some of the time, here i am referring to the difference tween aether theory & SR. Both give identical answers some of the time. Both use Lorentz transformations, length dilation, & time dilation. Both use Pythagorus, with sides c & v. Therefore it should be no surprise that both give the same answer in some specific cases.

Re censorship, i have 20 articles or links under this heading in my computer, & many more under different headings but could be under this heading. I am not talking about dissident scientists or sceptical papers etc (of which there must be 1000,s), i am talking about articles re censorship itself. Googling will find plenty of stuff in all categories.

Of course there are cranks, some so bad that i suspect that they are planted by sniggering Einsteinians (who are paid for their work).

I steer clear if any mention of multiverses, parallel universes, hologram universes, multi-dimensions, string theory, electric universe, expanding earth, etc etc.

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Strange.

Too simplistic for two reasons. The law should acknowledge that it doesn't apply if observers are moving in the plane of symmetry splitting the events.

It is not a "law"; it is a conclusion from the assumption (predicted by Maxwell's equations and confirmed by thousands of experiments to ridiculous levels of accuracy) that the speed of light is invariant.

And it does apply if the observers are moving in the plane of symmetry you describe. It is just slightly more complex to analyse. The simplest possible example is chosen to demonstrate the principle.

And anyhow it should be worded in some other way -- i suggest that it should say that the clock in an observer's frame will not give the same time (for the event) compared to another observer's clock (this observer moving relative to the first).

That appears to be statement about time dilation, not relativity of simultaneity.

Re SR being correct some of the time, here i am referring to the difference tween aether theory & SR. Both give identical answers some of the time. Both use Lorentz transformations, length dilation, & time dilation. Both use Pythagorus, with sides c & v. Therefore it should be no surprise that both give the same answer in some specific cases.

By saying SR is correct "some of the time" you imply that the rest of the time, it is wrong. Please provide some specific examples where SR has been shown to be wrong. You said it is wrong 100 times more often than it is right, so it should be possible for you to come up with one or two specific examples (not more of your vague handwaving).

Re censorship, i have 20 articles or links under this heading in my computer, & many more under different headings but could be under this heading. I am not talking about dissident scientists or sceptical papers etc (of which there must be 1000,s), i am talking about articles re censorship itself. Googling will find plenty of stuff in all categories.

As, once again, you are unable to provide any examples, I will have to assume this is not true.

Edited by Strange
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Strange.

I googled censorship in science & indeed it is difficult to find anything. Pages of stuff about politics & global warming & Trump etc.

I cant paste links, but if u google -- "the corruption of science in America" -- (by J Marvin Herndon)(2011), the article (link) will come up ok.

But this-here thread is about SR & the train experiment, so let me think of something smelly somewhere on the platform.

Yes, i have an example pointing at something that stinks.

The train experiment, or at least Einstein's extension of it, relies on being able to synchronise clocks. Einstein's method is to time a beam of light that goes from A to B, & reflected back B to A. The clock at B is then re-set & synchronised based on a half of that time. If the speed of light A-B is not identical to B-A then this synchronisation method is kaput.

There is a better method of synchronising clocks A & B, which as we all know involves moving a clock C very slowly from A to B. But, this doesn't save the day for Einstein. If speed A-B is different to B-A then the whole of SR is kaput, dead, finished.

"Light Transmission and the Sagnac Effect on the Rotating Earth" -- by Stephan J G Gift (Sept 3 2013).

Mentions that GPS shows that signals on Earth going west-to-east are slower than signals going east-to-west.

Einsteinians accept this anomaly, but instead of admitting that SR & GR are wrong, they apply what they call the Sagnac correction, and continue on their merry way as if that answers that. No, it don't.

"The GPS and the Constant Velocity of Light" -- by Paul Marmet.

This mentions same, & has some interesting wordage re west-to-east & east-to-west stuff.

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Strange.

I googled censorship in science & indeed it is difficult to find anything. Pages of stuff about politics & global warming & Trump etc.

I cant paste links, but if u google -- "the corruption of science in America" -- (by J Marvin Herndon)(2011), the article (link) will come up ok.

But this-here thread is about SR & the train experiment, so let me think of something smelly somewhere on the platform.

Yes, i have an example pointing at something that stinks.

The train experiment, or at least Einstein's extension of it, relies on being able to synchronise clocks. Einstein's method is to time a beam of light that goes from A to B, & reflected back B to A. The clock at B is then re-set & synchronised based on a half of that time. If the speed of light A-B is not identical to B-A then this synchronisation method is kaput.

There is a better method of synchronising clocks A & B, which as we all know involves moving a clock C very slowly from A to B. But, this doesn't save the day for Einstein. If speed A-B is different to B-A then the whole of SR is kaput, dead, finished.

"Light Transmission and the Sagnac Effect on the Rotating Earth" -- by Stephan J G Gift (Sept 3 2013).

Mentions that GPS shows that signals on Earth going west-to-east are slower than signals going east-to-west.

Einsteinians accept this anomaly, but instead of admitting that SR & GR are wrong, they apply what they call the Sagnac correction, and continue on their merry way as if that answers that. No, it don't.

"The GPS and the Constant Velocity of Light" -- by Paul Marmet.

This mentions same, & has some interesting wordage re west-to-east & east-to-west stuff.

S.J. Gift is a crackpot.

Paul Marmet was another crackpot.

The speed of light is isotropic.

Stop posting rubbish.

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...

Yes, i have an example pointing at something that stinks.

The train experiment, or at least Einstein's extension of it, relies on being able to synchronise clocks. Einstein's method is to time a beam of light that goes from A to B, & reflected back B to A. The clock at B is then re-set & synchronised based on a half of that time. If the speed of light A-B is not identical to B-A then this synchronisation method is kaput.

That's complete rubbish. The train/embankment thought experiment that introduces the relativity of simultaneity specifically avoids the need for any clock synchronisation by placing each observer between the location of each event - so simply seeing the events at the same time is sufficient to judge whether the events occured at the same time.

Nobody needs to synchronise any clock for this experiment. Please stop making stuff up.

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Argh. Silly board software appends posts

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I don't see where you get this.

See your words that I've underlined:

See my post 21: The train observer says:

<< IF both flashes also occur simultaneously for me when (at the moment in time) I meet the platform observer, THEN both light beams HAVE TO reach me simultaneously. But.... the lights from the bolts DO NOT reach me simultanously, hence the two events DID NOT occur simultaneously for me.>>

It's your insistence on referring to the embankment observer.

That's totally unnecessary.

Again, the experiment has them "meeting" when the embankment observer considers the strikes to have occurred. That's in the setup of the thought experiment, have you read it lately? To still be "meeting" the embankment observer when the strikes are seen would require the observers to have no relative velocity. That's the trivial case, and forcing it in your way detracts from the simple elegance of the experiment.

(

Just by way of counter example, consider another train observer, M'', seated behind M', in an otherwise unchanged experiment setup and outcome. That observer might indeed "meet" (your word) the platform observer at the same time as the flashes simultaneously reach the platform observer. (Pretty fast train!)

That fulfills your condition - but does not mean the flashes were simultaneous for M''!

a) From the M'' point of view, they did see the flashes at the same time, but they were not exactly between where the events occurred, so the events were not simultaneous.

b) From the M' point of view, the front strike occurred first and the rear strike occurred later. M'' is closer to the rear strike and further from the front strike, so M'' seeing the flashes at the same time does not contradict the M' view that the strikes were not simultaneous.

It all makes sense, M' and M'' agree that the strikes were not simultaneous, and this does not require reference to the embankment observer. That M'' happens to be adjacent to the embankment observer when the flashes reach the embankment observer, has little more relevance than that M' was adjacent to the embankment observer when the embankment observer considers the strikes to have occurred.

)

Maybe I had better said: <<If both flashes WOULD also occur simultaneously for me ... >> ? Sorry, english is my third language....

Doesn't make a difference, it's your insistence on making the train observer refer to the embankment observer that's the problem.

(Maybe ... not so much a "problem", as not a reason to have objected to my original post. That is, I don't think you are all that wrong, I just don't think your "correction" of my summary of the thought experiment adds anything, I think you make the explanation more complicated while adding no required detail.)

Edited by pzkpfw
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Yes, i have an example pointing at something that stinks.

The train experiment, or at least Einstein's extension of it, relies on being able to synchronise clocks.

Where are clocks synchronised, or even used, in this example?

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pzkpfw. Strange.

I did say -- or at least Einstein's extension of it.

In the sister-thread -- Einstein's train & me -- i mention 18 train experiments (in his 1920 book), & the famous twin lightning experiment is No12 -- & Einstein does his rod & clock routine in No 9 & 10 & 11 & 13.

zztop.

Lemmeseenow -- my advice that the speed of light is anisotropic is rubbish because the speed of light is isotropic. Ok, i get it.

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pzkpfw. Strange.

I did say -- or at least Einstein's extension of it.

In the sister-thread -- Einstein's train & me -- i mention 18 train experiments (in his 1920 book), & the famous twin lightning experiment is No12 -- & Einstein does his rod & clock routine in No 9 & 10 & 11 & 13.

So maybe we should stick to the topic of this thread. Instead of introducing extraneous and irrelevant objections.

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See your words that I've underlined:

It's your insistence on referring to the embankment observer.

That's totally unnecessary.

Again, the experiment has them "meeting" when the embankment observer considers the strikes to have occurred. That's in the setup of the thought experiment, have you read it lately? To still be "meeting" the embankment observer when the strikes are seen

This is really getting ridiculous. Stop inventing things I didn't say. I NEVER said an observer meets the other observer when the strikes are seen.

I said that IF the two events would ALSO occur simultaneously for the train observer, THEN the beams should reach the train observer simultaneously. BUT the train observer experiences they DON'T reach him (the train observer) simultaneously, hence the two flash events DID NOT occur simultanelously for the train observer.

It's all about whether the two flashes at the ends of the train occur WHEN THE OBSERVERS ARE TOGETHER.

The embankment observer says that when they were together both flashes occurred simultaneously for him (embankment observer), the train observer says both flashes didn't occur simultaneously when they were together (which is correct because for the train observer NONE of the flash events occurred when they were together, but that's beyond the scope of the experiment which is only to know whether they happened simultaneously or not for the train observer. And the train observer gets the answer: the flashes didn't occur simultaneouslyfor him. Period.)

Very weird you don't understand what I write.

would require the observers to have no relative velocity. That's the trivial case, and forcing it in your way detracts from the simple elegance of the experiment.

(

Just by way of counter example, consider another train observer, M'', seated behind M', in an otherwise unchanged experiment setup and outcome. That observer might indeed "meet" (your word) the platform observer at the same time as the flashes simultaneously reach the platform observer. (Pretty fast train!)

That fulfills your condition - but does not mean the flashes were simultaneous for M''!

a) From the M'' point of view, they did see the flashes at the same time, but they were not exactly between where the events occurred, so the events were not simultaneous.

b) From the M' point of view, the front strike occurred first and the rear strike occurred later. M'' is closer to the rear strike and further from the front strike, so M'' seeing the flashes at the same time does not contradict the M' view that the strikes were not simultaneous.

It all makes sense, M' and M'' agree that the strikes were not simultaneous, and this does not require reference to the embankment observer. That M'' happens to be adjacent to the embankment observer when the flashes reach the embankment observer, has little more relevance than that M' was adjacent to the embankment observer when the embankment observer considers the strikes to have occurred.

)

Doesn't make a difference, it's your insistence on making the train observer refer to the embankment observer that's the problem.

(Maybe ... not so much a "problem", as not a reason to have objected to my original post. That is, I don't think you are all that wrong, I just don't think your "correction" of my summary of the thought experiment adds anything, I think you make the explanation more complicated while adding no required detail.)

It was not a 'correction'. Did I say it was wrong what you stated?

I said to be careful when stating <<2. Both observers, given the initial setup, are entitled to consider themselves as located between the two events>> because readin your sentence an unititiated reader might think that from the train observer's point of view he (train observer) is halfway the events WHEN BOTH EVENTS OCCUR (which is wrong, see above) . THAT is the reason why I should not phrase it like you did. But I never said it your senence was wrong.

Your analysis of what I said is wrong. And you keep on telling me it's wrong because you keep on reading what I didn't write. Very weird.

Edited by VandD
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zztop.

Lemmeseenow -- my advice that the speed of light is anisotropic is rubbish because the speed of light is isotropic. Ok, i get it.

What I said is that there are thousands of experiments confirming light speed isotropy. I also said that you should stop posting rubbish, this is a mainstream forum, not a crank one.

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This is really getting ridiculous. Stop inventing things I didn't say. I NEVER said an observer meets the other observer when the strikes are seen.

I said that IF the two events would ALSO occur simultaneously for the train observer, THEN the beams should reach the train observer simultaneously. BUT the train observer experiences they DON'T reach him (the train observer) simultaneously, hence the two flash events DID NOT occur simultanelously for the train observer.

Actually, that's pretty much fine - it's pretty much what I've been writing!. You've removed reference to the embankment observer here, and just rely on Einsteins convention for simultaneity.

But - that's not what you wrote earlier. Post #29, you write (my underline) "IF both flashes also occur simultaneously for me when (at the moment in time) I meet the platform observer, THEN ...".

It's all about whether the two flashes at the ends of the train occur WHEN THE OBSERVERS ARE TOGETHER.

(Sounds of brakes squeeling) Hang on! You've just reversed yourself in this one post!

The embankment observer says that when they were together both flashes occurred simultaneously for him (embankment observer), the train observer says both flashes didn't occur simultaneously when they were together (which is correct because for the train observer NONE of the flash events occurred when they were together, but that's beyond the scope of the experiment which is only to know whether they happened simultaneously or not for the train observer. And the train observer gets the answer: the flashes didn't occur simultaneouslyfor him. Period.)

Very weird you don't understand what I write.

I can only understand what you write, not what you are thinking. And what you write is a bit muddled.

Whether they are together or not isn't the point. The train observer doesn't care whether they are together with the embankment observer, either when the strikes occur or the flashes are seen; all they care about is whether they themselves saw the flashes of the equidistant strikes at the same time.

What you wrote earlier in this post (your post #40) is much better. But, here, you're back to making the observers consider where each other were. Way over complicating things; you make it seem like any hypothetical observer can't decide that events were not simultaneous unless they have a different observer in relative motion to them, who does think the events were simultaneous.

Einstein set up a much clearer, simpler, thought experiment than the one you're trying to describe.

It was not a 'correction'. Did I say it was wrong what you stated?

Close enough.

I said to be careful when stating <<2. Both observers, given the initial setup, are entitled to consider themselves as located between the two events>> because readin your sentence an unititiated reader might think that from the train observer's point of view he (train observer) is halfway the events WHEN BOTH EVENTS OCCUR (which is wrong, see above) . THAT is the reason why I should not phrase it like you did. But I never said it your senence was wrong.

That's pretty weak. It's clear here that physical location is being written about.

Anyway, if that's your real issue with my post, adding a few words to clarify that only location is meant, would be way preferable to your overly complex description. Perhaps ...

Based on http://www.bartleby.com/173/9.html , it boils down to:

(warning : in the past I've found the bartleby website to do "dodgy" things; found a better source once but lost it).

1. Both observers are entitled to consider themselves as at rest (and the other observer moving).

2. Both observers, given the initial setup, are entitled to consider themselves as equidistant from the location of the two events.

3. Either observer, if seeing the flashes at the same time, would then consider the events to be simultaneous.

4. The flashes are seen at the same time by the embankment observer, so the events happen to be simultaneous for them.

5. As shown from the embankment observers point of view, the flashes don't reach the train observer at the same time.

6. The flashes can't reach the train observer at the same time and also not reach the train observer at the same time.

7. So, the train observers experience can't contradict the embankment observers experience.

8. So the events were not simultaneous for the train observer.

9. Vice versa, two different events, which happen to be simultaneous for the train observer, won't be for the embankment observer.

(Bear in mind also this was only ever a summary of the original thought experiment, which I linked to. It's not a complete (replacement) description of the entire thing.)

((Edit: ... and that was for the benefit of madmac, to help him get over what seemed a misunderstanding blocking his comprehension. If it were not for him being (as I now see) a crank beyond help; your unnecessary complication is detrimental to that.))

Your analysis of what I said is wrong. And you keep on telling me it's wrong because you keep on reading what I didn't write. Very weird.

English is my first language, you've said English is your third; and here in this single post (#40) you contradict yourself. Weird? Odd? I stand by my interpretation of your posts.

Edited by pzkpfw
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Actually, that's pretty much fine - it's pretty much what I've been writing!. You've removed reference to the embankment observer here, and just rely on Einsteins convention for simultaneity.

But - that's not what you wrote earlier. Post #29, you write (my underline) "IF both flashes also occur simultaneously for me when (at the moment in time) I meet the platform observer, THEN ...".

Indeed. And you forgot once more to read what followed: << But.... the lights from the bolts DO NOT reach me simultanously, hence the two events DID NOT occur simultaneously for me>>

(Sounds of brakes squeeling) Hang on! You've just reversed yourself in this one post!

I can only understand what you write, not what you are thinking. And what you write is a bit muddled.

Whether they are together or not isn't the point.

You are wrong. The whole gedanken experiment is the find out whether for the embankment observer AND train observer the two events occured simultaneousy WHEN THE OBSERVERS WERE TOGETHER.

The embankment observer says that when they were together both flashes occurred simultaneously for him (embankment observer), the train observer says both flashes didn't occur simultaneously when they were together.

That's the relativity of simultaneity to be proved. Both observers are at the same spot, but disagree on simultaneity of spacelike like events.

The train observer doesn't care whether they are together with the embankment observer, either when the strikes occur or the flashes are seen; all they care about is whether they themselves saw the flashes of the equidistant strikes at the same time.

Yes, and WHY is that important? TO FIND OUT WHETHER THE EVENTS OCCURRED SIMULTANEOUSLY FOR THE TRAIN OBSERVER WHEN THEY WERE TOGETHER, AND WHETHER THE EVENTS OCCURRED SIMULTANEOUSLY FOR THE TRAIN OBSERVER WHEN THEY WERE TOGETHER!

What you wrote earlier in this post (your post #40) is much better. But, here, you're back to making the observers consider where each other were. Way over complicating things; you make it seem like any hypothetical observer can't decide that events were not simultaneous unless they have a different observer in relative motion to them, who does think the events were simultaneous.

Einstein set up a much clearer, simpler, thought experiment than the one you're trying to describe.

Close enough.

That's pretty weak. It's clear here that physical location is being written about.

Anyway, if that's your real issue with my post, adding a few words to clarify that only location is meant, would be way preferable to your overly complex description. Perhaps ...

(Bear in mind also this was only ever a summary of the original thought experiment, which I linked to. It's not a complete (replacement) description of the entire thing.)

((Edit: ... and that was for the benefit of madmac, to help him get over what seemed a misunderstanding blocking his comprehension. If it were not for him being (as I now see) a crank beyond help; your unnecessary complication is detrimental to that.))

English is my first language, you've said English is your third; and here in this single post (#40) you contradict yourself. Weird? Odd? I stand by my interpretation of your posts.

I give up, pzk, I see it's hopeless continue discussing this with you. Good luck.

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Indeed. And you forgot once more to read what followed: << But.... the lights from the bolts DO NOT reach me simultanously, hence the two events DID NOT occur simultaneously for me>>

That's not the issue. The issue is your insistence on the train observer referring to the embankment observer. The bit you emphasis in the line above, is the same as I've been writing, and the same as you've been writing - that I've been agreeing with.

You are wrong. The whole gedanken experiment is the find out whether for the embankment observer AND train observer the two events occured simultaneousy WHEN THE OBSERVERS WERE TOGETHER.

No. Try using a larger font, if you like, maybe red text ... I'll still say no.

The whole gedanken experiment is the find out whether for the embankment observer AND train observer the two events occurred simultaneously.

Whether they're together or not isn't the point. The last bit of that line of yours isn't needed.

(Heck, you could have a variation of the gedanken experiment with another embankment observer, twice as close to one strike as the other, who sees the flashes at different times, but who (using their non-equidistant position and the speed of light) knows/calculates that the strikes (events) were actually simultaneous. That observer is not "together" with the original embankment observer at either the time of the events occurring or the seeing of the events - but still agrees with that observer.)

You are fixated on the wrong aspect of the experiment.

The embankment observer says that when they were together both flashes occurred simultaneously for him (embankment observer), the train observer says both flashes didn't occur simultaneously when they were together.

That's the relativity of simultaneity to be proved. Both observers are at the same spot, but disagree on simultaneity of spacelike like events.

They don't need to consider that they were together to know that.

M and M' both are equidistant to the two events.

M and M' are stationary in their own view.

M sees the events at the same time, so considers the events to be simultaneous.

M' does not see the events at the same time, so does not consider the events to be simultaneous.

They don't need to refer to each other. We do use the view of M to show that M' wouldn't see the flashes at the same time, but the original words of the gedanken experiment show that very simply, without your unnecessary complication.

Yes, and WHY is that important? TO FIND OUT WHETHER THE EVENTS OCCURRED SIMULTANEOUSLY FOR THE TRAIN OBSERVER WHEN THEY WERE TOGETHER, AND WHETHER THE EVENTS OCCURRED SIMULTANEOUSLY FOR THE TRAIN OBSERVER WHEN THEY WERE TOGETHER!

You're still emphasising the trivial case. If they are together when the events occur and together when the events are seen (the case for the embankment observer in this setup), they are not in relative motion, so would agree on simultaneity.

The experiment stipulates they are "together" when the embankment observer considers the events to have occurred, and according to the embankment observer the train observer is moving so the train observer isn't still "together" when the embankment observer see the flashes. But the simple point is that (according to the embankment observer) the train observer is moving towards the location of one event and away from the location of the other - so won't see the flashes at the same time.

In reverse, the train observer simply sees the flashes at the same time. The train observer isn't referencing themselves to the embankment observer.

You can add whatever post-hoc analysis you want about who was where, when, but it's not needed.

I give up, pzk, I see it's hopeless continue discussing this with you. Good luck.

Cool.

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zztop.

Re those thousands of confirmations re isotropy of c. U should cross off any of the M&M ones that are done in vacuum.

Vacuum gives a null result according to Prof Reg Cahill (because the refractive index is 1.0000) who gives the correct calibration for gas mode M&M experiments in --

The Michelson and Morley 1887 Experiment and the discovery of absolute motion -- 2005, Progress In Physics.

This must i think also apply to some experiments using vacuum lasers & vacuum etalons.

Helium-Neon has a very low refractive index & hencely must be little better than vacuum i think. Air is ok.

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zztop.

Re those thousands of confirmations re isotropy of c. U should cross off any of the M&M ones that are done in vacuum.

Vacuum gives a null result according to Prof Reg Cahill (because the refractive index is 1.0000) who gives the correct calibration for gas mode M&M experiments in --

The Michelson and Morley 1887 Experiment and the discovery of absolute motion -- 2005, Progress In Physics.

This must i think also apply to some experiments using vacuum lasers & vacuum etalons.

Helium-Neon has a very low refractive index & hencely must be little better than vacuum i think. Air is ok.

Reg Cahill is yet another crank, he makes the same errors as Demjanov. Progress in Physics is a crackpot journal. Cease and desist.

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zztop.

I couldn't follow Cahill's derivation of his M&M calibration equation, however as usual i simply used some simple equations in an Excel table to calculate time difference in the 2 M&M arms & i got his answers, which convinced me he is correct. A good article re all this is --

"Review of Experiments that Contradict Special Relativity and Support Neo-Lorentz Relativity: Latest Technique to Detect Dynamical Space Using Quantum Detection (2015) -- Baltimore Conference.

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zztop.

I couldn't follow Cahill's derivation of his M&M calibration equation, however as usual i simply used some simple equations in an Excel table to calculate time difference in the 2 M&M arms & i got his answers, which convinced me he is correct. A good article re all this is --

"Review of Experiments that Contradict Special Relativity and Support Neo-Lorentz Relativity: Latest Technique to Detect Dynamical Space Using Quantum Detection (2015) -- Baltimore Conference.

Cahill is a crank.

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...

In reverse, the train observer simply sees the flashes at the same time different times. The train observer isn't referencing themselves to the embankment observer.

...

Oops. Typo (got observers mixed up in one place, in post #44) too late to edit. Waste of time, probably, but corrected (consistent with everything else I've written).

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With emphasis mine:

What I said is that there are thousands of experiments confirming light speed isotropy. I also said that you should stop posting rubbish, this is a mainstream forum, not a crank one.

Not just "mainstream" but a simple fact: experiments that clearly use a one-way light path and find isotropy are inherently unable to rule out a large class of theories in which the one-way speed of light is anisotropic

( Yes I'm back )

Cahill is a crank.

While that may be true, it's up to us to demonstrate that by means of scientific arguments. Mud throwing is particularly unscientific.

PS I read: "In 2010 the Telesio - Galilei Academy of Science awarded Professor Reg Cahill a Gold Medal for the development of Process Physics. The ceremony was held at the University of Pecs, Hungary."

Not bad for a "crank"!

Edited by Tim88

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