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Tags Allais Effect , Dark Flow , relativity , Theory of Relativity

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Old 6th August 2019, 06:05 PM   #201
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I was driving around this really fat guy well after midnight on 11/4/18. It was 1:59 am then seconds later it was 1:00am. Time actually went backwards. Earlier in the year I was driving fast and at the 1:59 am, a minute later my phone clock read 3:00 am. Explain that sheeple!
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Old 6th August 2019, 11:14 PM   #202
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Bah. I've had worse. I was travelling once and the calendar went backwards by one day. I returned and the missing day came back.
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Old 23rd August 2019, 04:21 PM   #203
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Well known Einstein's train embankment thought experiment. The train car moves at speed v=c/5 and conductor in the middle of the train car sends light pulse in the forward directions along the track at t=t'=0. The platform observer and the conductor wait till the pulse hits the front of the train car at 7.5s of the platform time and 6.123724s of the train frame. The blue wave is the pulse as seen by the platform observer.




Now we know that f=c/\lambda and we can see that f=f' because the wave has the period T=1 in both frames and f=1/T therefore it should follow that c/\lambda=c/\lambda'.
The last equation is a false statement because \lambda and \lambda' are not equal and if it suppose to be true then c is not constant in both frames.

Who is going to defend the second postulate?
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Old 23rd August 2019, 11:43 PM   #204
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It's difficult to know where to start to correct your misunderstanding, SDG.

I can recommend this free online course on special relativity:

https://www.coursera.org/learn/einst...y/home/welcome

If you still have questions after completing it, I'm sure someone here will be able to answer them.
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Old 25th August 2019, 06:17 AM   #205
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Originally Posted by SDG View Post
Well known Einstein's train embankment thought experiment. The train car moves at speed v=c/5 and conductor in the middle of the train car sends light pulse in the forward directions along the track at t=t'=0. The platform observer and the conductor wait till the pulse hits the front of the train car at 7.5s of the platform time and 6.123724s of the train frame. The blue wave is the pulse as seen by the platform observer.

https://i.imgur.com/n9K09I7.png


Now we know that f=c/\lambda and we can see that f=f' because the wave has the period T=1 in both frames and f=1/T therefore it should follow that c/\lambda=c/\lambda'.
The last equation is a false statement because \lambda and \lambda' are not equal and if it suppose to be true then c is not constant in both frames.

Who is going to defend the second postulate?
This part "that f=f' because the wave has the period T=1 in both frames and f=1/T"

Is refuted by this part "at 7.5s of the platform time and 6.123724s of the train frame."

While time in each frame may only be one cycle (one wave period) for each observer that doesn't make the measured time equal for each observer. In fact it was explicitly stated, by you, not to be equal in the experiment description. Thus f can not equal f' since elapsed time for each is only one cycle and as explicitly stated by you elapsed t ("6.123724s") does not equal elapsed t' ("7.5s"). You note the time dilation in your set up but then simply ignore it in your assertion of f=f'.

If your claim is about the symmetry of SR then the observer on the platform would have to also send a light signal and each observer would see the same frequency shift in the others signal.
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Old 25th August 2019, 06:54 AM   #206
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Originally Posted by SDG View Post
Well known Einstein's train embankment thought experiment. The train car moves at speed v=c/5 and conductor in the middle of the train car sends light pulse in the forward directions along the track at t=t'=0. The platform observer and the conductor wait till the pulse hits the front of the train car at 7.5s of the platform time and 6.123724s of the train frame. The blue wave is the pulse as seen by the platform observer.

https://i.imgur.com/n9K09I7.png


Now we know that f=c/\lambda and we can see that f=f' because the wave has the period T=1 in both frames and f=1/T therefore it should follow that c/\lambda=c/\lambda'.
The last equation is a false statement because \lambda and \lambda' are not equal and if it suppose to be true then c is not constant in both frames.

Who is going to defend the second postulate?
Allow me a general comment on this:

The theory of relativity has been scrutinized with great care for over a century by millions of excellent brains. Putting the slightest dent into it has been the wet dream of thousands of scientists, as it would propel them straight to fame and fortune (or at least prestigious professorats).

If you can design a simple theoretical scenario that seems to refute it, rest assured you have made some mistake. Therefore, don't demand that others find your mistake for you; go back and study the theory more.

Hans
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Old 26th August 2019, 09:01 AM   #207
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Originally Posted by The Man View Post
This part "that f=f' because the wave has the period T=1 in both frames and f=1/T"

Is refuted by this part "at 7.5s of the platform time and 6.123724s of the train frame."

While time in each frame may only be one cycle (one wave period) for each observer that doesn't make the measured time equal for each observer. In fact it was explicitly stated, by you, not to be equal in the experiment description. Thus f can not equal f' since elapsed time for each is only one cycle and as explicitly stated by you elapsed t ("6.123724s") does not equal elapsed t' ("7.5s"). You note the time dilation in your set up but then simply ignore it in your assertion of f=f'.

If your claim is about the symmetry of SR then the observer on the platform would have to also send a light signal and each observer would see the same frequency shift in the others signal.

Here is an image that shows the platform observer sending his own light pulse at t=t'=0, the light blue, of the same wave length as the dark red pulse and how the light blue light pulse is observed by the train observer, the light red.



Is this image correct representation of what is happening?
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Old 26th August 2019, 09:28 AM   #208
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Originally Posted by SDG View Post
Well known Einstein's train embankment thought experiment. <snippage of half-baked, poorly illustrated gibberings>
Who is going to defend the second postulate?
This is utter rubbish. I suggest you study relativity, and it's proofs, before you try to expound on it.
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Old 26th August 2019, 10:53 AM   #209
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Originally Posted by SDG View Post
Here is an image that shows the platform observer sending his own light pulse at t=t'=0, the light blue, of the same wave length as the dark red pulse and how the light blue light pulse is observed by the train observer, the light red.

https://i.imgur.com/M4M9A5p.png

Is this image correct representation of what is happening?
Look, it does not seem anybody here is in the mood to teach you about the theory of relativity. So I suggest you find other avenues to study it. Once you have done that you may be able to ask questions that people will be interested in trying to answer.

Hans
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Old 26th August 2019, 11:42 AM   #210
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Has relativity fallen apart yet?
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Old 26th August 2019, 03:40 PM   #211
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Originally Posted by MRC_Hans View Post
Look, it does not seem anybody here is in the mood to teach you about the theory of relativity. So I suggest you find other avenues to study it. Once you have done that you may be able to ask questions that people will be interested in trying to answer.

Hans
The relativity claims clock desynchronization at the black line on the image below "a now moment".



If we place a mechanical clocks at t=t'=0 in both frames, rotate the clock 90 degrees so the clock hands move only up and down in the y direction, the tips of the clock hands move on helix trajectories then there is no clock desynchronization. It cannot be, right?
So the light blue line platform clock can never catch up to the dark red train clock on the x axis for the same position in the "now moment".
If this happens for the mechanical clock then why it would not happen for the light clock?
This is the basis for the frequency/period claim I made.
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Old 26th August 2019, 03:45 PM   #212
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Originally Posted by SDG View Post
Here is an image that shows the platform observer sending his own light pulse at t=t'=0, the light blue, of the same wave length as the dark red pulse and how the light blue light pulse is observed by the train observer, the light red.

https://i.imgur.com/M4M9A5p.png

Is this image correct representation of what is happening?
Have you corrected the direct contradiction in your previous post? If not, images won't help that.

ETA: Also your original post said "t=t'=0" but your linked image here says t=0=1.5 (t') and t'=0=-1.5(t). Heck even your original image has that. So your images don't even represent just what you state.
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Last edited by The Man; 26th August 2019 at 03:57 PM. Reason: typo & ETA
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Old 26th August 2019, 03:47 PM   #213
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Originally Posted by SDG View Post
The relativity claims clock desynchronization at the black line on the image below "a now moment".

https://i.imgur.com/kEdo06J.png

If we place a mechanical clocks at t=t'=0 in both frames, rotate the clock 90 degrees so the clock hands move only up and down in the y direction, the tips of the clock hands move on helix trajectories then there is no clock desynchronization. It cannot be, right?
So the light blue line platform clock can never catch up to the dark red train clock on the x axis for the same position in the "now moment".
If this happens for the mechanical clock then why it would not happen for the light clock?
This is the basis for the frequency/period claim I made.
SDG

The "frequency/period claim" you made was self-contradictory, you need to address that first.
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Old 26th August 2019, 04:45 PM   #214
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Originally Posted by The Man View Post
Have you corrected the direct contradiction in your previous post? If not, images won't help that.

ETA: Also your original post said "t=t'=0" but your linked image here says t=0=1.5 (t') and t'=0=-1.5(t). Heck even your original image has that. So your images don't even represent just what you state.


This is t=t'=0 diagram.
If I show diagram for v=c/5 at 7.5s there is nothing wrong to talk about what happened at t=t'=0, initial conditions.
When I said the light pulse hit the front of the train car at 7.5s of the platform time then it follows the light crossed 7.5cs in the platform frame, this is clearly visible in the first image.

To clarify, the images show 12cs the length of the train car as it seen in the platform frame. The half of the train car is 6cs as seen in the platform frame.
... and the mechanical clocks would move at v_c<c in their respective frames of course.

Last edited by SDG; 26th August 2019 at 04:47 PM.
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Old 26th August 2019, 04:48 PM   #215
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Originally Posted by The Man View Post
The "frequency/period claim" you made was self-contradictory, you need to address that first.
It does not appear to me that the claim is self-contradictory.
I posted the reasoning behind the claim.
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Old 26th August 2019, 04:55 PM   #216
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Originally Posted by SDG View Post
https://i.imgur.com/2n0rZrX.png

This is t=t'=0 diagram.
If I show diagram for v=c/5 at 7.5s there is nothing wrong to talk about what happened at t=t'=0, initial conditions.
When I said the light pulse hit the front of the train car at 7.5s of the platform time then it follows the light crossed 7.5cs in the platform frame, this is clearly visible in the first image.

To clarify, the images show 12cs the length of the train car as it seen in the platform frame. The half of the train car is 6cs as seen in the platform frame.
... and the mechanical clocks would move at v_c<c in their respective frames of course.
t=t'=0 doesn't change even after "7.5s". By changing it in other diagrams you simply contradict your own assertion of t=t'=0 as the initial condition. Again you need to stop doing that, directly contradicting yourself, first.

This goes for you as well Bjarne.
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Old 26th August 2019, 05:02 PM   #217
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Originally Posted by SDG View Post
It does not appear to me that the claim is self-contradictory.
I posted the reasoning behind the claim.
Agian...

Originally Posted by The Man View Post
This part "that f=f' because the wave has the period T=1 in both frames and f=1/T"

Is refuted by this part "at 7.5s of the platform time and 6.123724s of the train frame."
.

Your self-contradiction is explicit in your own assertions.

If the time for one period is not the same in both frames then the frequency is not the same in both frames. You can reason anything from a contradiction held as true.


https://en.wikipedia.org/wiki/Principle_of_explosion
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Old 26th August 2019, 06:45 PM   #218
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Originally Posted by SDG View Post
Well known Einstein's train embankment thought experiment. ...
This is the well known and documented Einstein's train thought experiment that explains relativity of simultaneity, SDK. It is correct textbook physics thus your reasoning or understanding is wrong.
The Wikipedia page gives 3 explanations. Einstein's original logic shows an observer on a platform will witness two lightning bolts simultaneously striking both ends of a moving train but an observer on the train will see them strike at different times. The popular thought experiment replaces the lightning with a flash emitted from the middle of the train carriage. Then there is the more technical world line explanation.

Last edited by Reality Check; 26th August 2019 at 06:55 PM.
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Old 26th August 2019, 07:01 PM   #219
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Originally Posted by SDG View Post
Who is going to defend the second postulate?
You are the one suggesting there is something wrong with the second postulate. You have to defend your claim.

We have 114 years worth of tests of special relativity that show that it correctly describes the real world. See What is the experimental basis of Special Relativity?

Last edited by Reality Check; 26th August 2019 at 07:02 PM.
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Old 27th August 2019, 05:55 AM   #220
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Originally Posted by The Man View Post
t=t'=0 doesn't change even after "7.5s". By changing it in other diagrams you simply contradict your own assertion of t=t'=0 as the initial condition. Again you need to stop doing that, directly contradicting yourself, first.

This goes for you as well Bjarne.
Are you saying that origins 0 do not change their respective positions with time?
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Old 27th August 2019, 06:16 AM   #221
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The free course I linked to above uses Einstein's train scenarios throughout (except its examples use spaceships rather than trains). Studying just the first few lessons and working through the examples should help you understand the mistake you are making, SDG. It would be much quicker and easier than trying to get the same education by posing questions based on a fundamental misunderstanding and expecting random posters to try to correct it.
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Old 27th August 2019, 12:30 PM   #222
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Originally Posted by Pixel42 View Post
It's difficult to know where to start to correct your misunderstanding, SDG.

I can recommend this free online course on special relativity:

https://www.coursera.org/learn/einst...y/home/welcome

If you still have questions after completing it, I'm sure someone here will be able to answer them.
There's also this with award winning graphics (for the time).

https://www.youtube.com/playlist?lis...h5G0dk-XGtA5cZ


One for SDG.

YouTube Video This video is not hosted by the ISF. The ISF can not be held responsible for the suitability or legality of this material. By clicking the link below you agree to view content from an external website.
I AGREE
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Old 27th August 2019, 01:38 PM   #223
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Originally Posted by SDG View Post
Are you saying that origins 0 do not change their respective positions with time?
The stated origins in time (t=t'=0) don't and can't change with time. Otherwise they could not be the stated origins in time. Fundamentally t=t'=0 says that the train and platform observes clocks both start inn there respective frames at 0 the start of the experiment. Again, while you do note the later discrepancy in measured time with the time dilation and the subsequent passage of time you then simply ignore that for your claim of f=f'.

https://en.wikipedia.org/wiki/Relati...f_simultaneity
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Old 29th August 2019, 08:53 AM   #224
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Originally Posted by The Man View Post
The stated origins in time (t=t'=0) don't and can't change with time. Otherwise they could not be the stated origins in time. Fundamentally t=t'=0 says that the train and platform observes clocks both start inn there respective frames at 0 the start of the experiment. Again, while you do note the later discrepancy in measured time with the time dilation and the subsequent passage of time you then simply ignore that for your claim of f=f'.

https://en.wikipedia.org/wiki/Relati...f_simultaneity
Please, have a look here:



If I understand you correctly you say that there is only one t=t'=0 and x=x'=0 point in space-time and it does not change, and I agree.
Having said that the period, the frequency and the wavelength of a wave are defined within one frame.

The relativity claims that any clock should experience the time dilation.
The image shows one period of one clock, rotated 90 degrees so the clock hands move on a helix trajectory, as seen in two frames where the clock hand moves one circle and how it is observed in both frames.
f=f'=1, T=T'=1, \lambda=8, \lambda'=4, v_clk_platform = 8, v_clk_train = 4
Where is the time dilation?
Is there a difference between light clock and the mechanical clock?
SDG
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Old 29th August 2019, 01:51 PM   #225
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Originally Posted by SDG View Post
The relativity claims that any clock should experience the time dilation.
That is not quite right, SDG.

Read the science given to you: Relativity of simultaneity. Note the absence of clocks in the thought experiments (clocks are mentioned in the context of synchronizing them). The train thought experiment itself is not about time dilation. It is about what observers observe. One will observe the lightning bolts hitting the ends of the carriage at the same time. The other will observe 1 bolt hit before the other bolt.

Special relativity derives that observers of clocks moving relative to them will measure time dilation. 114 years of experimental tests confirms that time dilation exists and matches SR. If we give the observers in the train thought experiment clocks then the clocks will experience time dilation. It is very wrong to state that clocks in a moving frame of reference will not experience time dilation.
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Old 29th August 2019, 02:12 PM   #226
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Originally Posted by Reality Check View Post
That is not quite right, SDG.

Read the science given to you: Relativity of simultaneity. Note the absence of clocks in the thought experiments (clocks are mentioned in the context of synchronizing them). The train thought experiment itself is not about time dilation. It is about what observers observe. One will observe the lightning bolts hitting the ends of the carriage at the same time. The other will observe 1 bolt hit before the other bolt.

Special relativity derives that observers of clocks moving relative to them will measure time dilation. 114 years of experimental tests confirms that time dilation exists and matches SR. If we give the observers in the train thought experiment clocks then the clocks will experience time dilation. It is very wrong to state that clocks in a moving frame of reference will not experience time dilation.
Indeedy. The story of the NAVSTAR satellites (the first GPS satellites) is a very interesting one. Neil Ashby tells of how they still had people (probably bloody engineers!) who thought relativistic corrections would not be needed. Fortunately, they included a synthesiser that could bring the clock back into alignment should these relativistic corrections prove necessary. They were. More to the point, they were within 3 trillionths of a second of the predictions of scientists prior to launch. Much written on this, but this is a good starting point;

http://www.leapsecond.com/history/Ashby-Relativity.htm
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Old 31st August 2019, 07:21 AM   #227
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Originally Posted by SDG View Post
Please, have a look here:

https://i.imgur.com/5ANMESf.png

If I understand you correctly you say that there is only one t=t'=0 and x=x'=0 point in space-time and it does not change, and I agree.
Technically, it was you who said "t=t'=0". Disagreeing with that you would be just disagreeing with yourself.

Originally Posted by SDG View Post
Having said that the period, the frequency and the wavelength of a wave are defined within one frame.
Well then you've got a problem and disagreement with yourself as your diagram shows two wavelengths from two frames and your description noted two different wave periods for the two frames.

Originally Posted by SDG View Post
The relativity claims that any clock should experience the time dilation.
The image shows one period of one clock, rotated 90 degrees so the clock hands move on a helix trajectory, as seen in two frames where the clock hand moves one circle and how it is observed in both frames.
f=f'=1, T=T'=1, \lambda=8, \lambda'=4, v_clk_platform = 8, v_clk_train = 4
Where is the time dilation?
In your original post it was stated by you as "the pulse hits the front of the train car at 7.5s of the platform time and 6.123724s of the train frame.". As you regard each of those times to be the period of the wave in each frame f can not = f'.


Originally Posted by SDG View Post
Is there a difference between light clock and the mechanical clock?
SDG
Not that I'm aware of, as far as relativity is concerned anyway.
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Old 3rd September 2019, 01:53 PM   #228
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Originally Posted by The Man View Post
Technically, it was you who said "t=t'=0". Disagreeing with that you would be just disagreeing with yourself.



Well then you've got a problem and disagreement with yourself as your diagram shows two wavelengths from two frames and your description noted two different wave periods for the two frames.



In your original post it was stated by you as "the pulse hits the front of the train car at 7.5s of the platform time and 6.123724s of the train frame.". As you regard each of those times to be the period of the wave in each frame f can not = f'.




Not that I'm aware of, as far as relativity is concerned anyway.
I am not sure you understand the point I am trying to make.

Nevertheless, the Lorentz transformation is symmetrical, the reciprocity is true.
It means that two inertial observers cannot settle who's clock is going slower.
It means they do not agree on time.
This means that two inertial observers do not agree on anything over delta time.
That's it.
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Old 3rd September 2019, 02:15 PM   #229
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Originally Posted by SDG View Post
I am not sure you understand the point I am trying to make.

Nevertheless, the Lorentz transformation is symmetrical, the reciprocity is true.
It means that two inertial observers cannot settle who's clock is going slower.
It means they do not agree on time.
This means that two inertial observers do not agree on anything over delta time.
That's it.
I'm sure you still don't understand the point I have been making to you. You first have to stop contradicting yourself.

This part...

"It means that two inertial observers cannot settle who's clock is going slower.
It means they do not agree on time."

Contradicts this part...

"This means that two inertial observers do not agree on anything over delta time."

If they "do not agree on time" then they can not agree on "delta time". Because that is all any time is, just a measure of "delta time" from some other point in time. Just as any location in space is just the measure of some metric from some other location in space.

Again, your original description even asserts that they don't agree on the delta time for the light to reach the front of the train (which is one cycle of the wave in your diagram). Hence, again, f can not = f'.
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Old 3rd September 2019, 03:18 PM   #230
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Originally Posted by SDG View Post
...That's it.
A bit vague but looks wrong, SDG. Observers do not agree on simultaneity as in relativity of simultaneity.
Two inertial observers can settle who's clock is going slower. For 2 observers Alice and Bob, they will agree that Alice will measure Bob's clock to be slower and that Bob will measure Alice's clock is going slower. The time dilation will be the same.

Once again - this is not clocks. It is observers noting the sequence of events.
30 August 2019 SDG: Note the absence of clocks in the thought experiments for relativity of simultaneity.

Last edited by Reality Check; 3rd September 2019 at 03:22 PM.
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Old 3rd September 2019, 10:11 PM   #231
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Have you started that free online course on special relativity yet, SDG? It really does answer all of your questions.
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Old 4th September 2019, 05:20 AM   #232
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Originally Posted by Pixel42 View Post
Have you started that free online course on special relativity yet, SDG? It really does answer all of your questions.

No, I'll present the thought experiment with calculations and everyone will be able to see if I need one.
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Old 4th September 2019, 05:33 AM   #233
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Light, Time and Simultaneity


Well known Einstein's train embankment thought experiment is being used to explain the concept of relativity of simultaneity almost in every text book. The train car moves at speed v and conductor in the middle of the train car sends simultaneously two light pulses in the opposite directions along the track. The platform observer and the conductor wait how the pulses hit the ends of the train car. The conductor sees both pulses to hit the end of the train car at the same time. If L’ is the length of the train car measured by the conductor then t’_left = t’_right = L’/2c. The platform observer sees a different result. If L is the length of the train car measured by the platform observer then t_left = L/2(c+v) and t_right = L/2(c-v), in other words t_left < t_right. The fundamental question is how ONE Lorentz transformation factor gamma between the train car reference frame and the platform reference frame can give us TWO different time dilations for the platform frame when there is only ONE time in the moving train car frame, ONE velocity v and the speed of light c is constant for both reference frames? The relativistic explanation is that the Lorentz transformation time component is a function of distance therefore the clock desynchronization of the light propagation in the left/right directions has the issue covered. The light speed c as the distance travelled over the time when time is measured as a delta on desynchronized clocks within each reference frame is constant and equal between the two reference frames.
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Old 4th September 2019, 05:44 AM   #234
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The light propagation

When a photon is emitted from a source it propagates through the space on its own merit, it is independent from the source of the emission. Let us consider a thought experiment with two light sources, one on a train car and one on a platform outside the train car. Coordinates t and x represent the platform reference frame and coordinates t’ and x’ represent the train reference frame. Both reference frames have their clocks synchronized within their respective frames prior to the start of the experiment. When the light sources are aligned, they emit light beams at the same time – the event C. The event marks the time t=0 and t’=0 on the aligned clocks and the position of the clocks is marked x=0 and x’=0. The light beams are split in the left and right directions as per Figure 1. The blue arrows represent the platform light and the red arrows represent the train light. The train velocity v is one fifth of the speed of light c; v=c/5 in the platform frame. The train and the platform light beams will travel next to each other and they will be observed travelling next to each other in all reference frames.




Figure 1: The train and platform light emissions in the left and right directions. The blue arrows represent the platform light and the red arrows represent train light. The train velocity is v=c/5 in the platform frame.


The light beams will hit the left end of the train car at event A and right end of the train car at event B. One grid spacing unit represents one light-second, ‘cs’ for short. The light moves at c in the platform frame. The train length is 12 spacing units, one half is 6 spacing units, 6 light-seconds or 6cs. At t=0, emission of the light, event C, the left end (LE) of the train car is at x=-6cs, the right end (RE) of the train car is at x=6cs. All figures show the analysis from the platform frame point of view. Figure 2 shows the event A where the blue arrows represent the same distance the light travelled in the platform frame. The red arrows show the distance travelled by the light at c+v and c-v as seen by the platform observer. The platform frame light speed c added to the train speed v=c/5 crosses the distance of 6 light-seconds in 6cs/(c+c/5) = 5s for the event A, LE light hit.



Figure 2: The left light beam hits the left end of the train car at event A. The blue arrows represent the same distance the light travelled in the platform frame in 5 seconds. The red left pointing arrow shows the distance travelled by the light at c+v and the red right pointing arrow shows the distance travelled by the light at c-v as seen by the platform observer. The light beams travel next to each other and they are observed travelling next to each other in both reference frames.

Last edited by SDG; 4th September 2019 at 05:53 AM.
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Old 4th September 2019, 05:56 AM   #235
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The origin x’=0 of the train moved one grid spacing in the platform frame in 5 seconds; the origin x’=0 is aligned with x=1.
The platform frame light speed c minus the train speed v=c/5 crosses the distance of 6 light-seconds in 6cs/(c-c/5) = 7.5s for the event B, RE light hit. Figure 3 captures the event B.



Figure 3: The right light beam hits the right end of the train car at event B. The blue arrows represent the same distance the light travelled in the platform frame in 7.5 seconds. The red left pointing arrow shows the distance travelled by the light at c+v and the red right pointing arrows show the distance travelled by the light at c-v as seen by the platform observer. The light beams travel next to each other and they are observed travelling next to each other in both reference frames.

The origin x’=0 of the train moved one and half grid spacing in the platform frame in 7.5 seconds; the origin x’=0 is aligned with x=1.5. We can make two very important observations. The first one: The AB event spacing is 12.5cs in the platform frame, the A’B’ events spacing is 12cs in the train frame. The second one: The events A and A’ became misaligned.

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Old 4th September 2019, 06:13 AM   #236
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Originally Posted by SDG View Post
No, I'll present the thought experiment with calculations and everyone will be able to see if I need one.
You need one.
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Old 4th September 2019, 06:22 AM   #237
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Originally Posted by SDG View Post
... The relativistic explanation is that the Lorentz transformation time component is a function of distance therefore ...
can you please explain that to me? the mathematical dependence of time from distance (?) will suffice
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Old 4th September 2019, 06:24 AM   #238
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Light speed calculation


The platform observer sees the light moving at c+v and c-v in the train frame and the train observer agrees with the platform observer, yes, the platform observer sees my light speed as c+v and c-v but the second postulate claims see my light speed as c in my train frame. When the platform observer calculates the light speed as distance over time in the train frame applying the Lorentz factor \gamma, time dilation, length contraction and clock desynchronization between the frames then the result will be the constant light speed c in the train frame.

gamma = 1/sqrt(1-(c/5)^2/c^2) = 1/sqrt(1-1/25) = 1/sqrt(24/25) = 1/sqrt(4*6/5*5) = 1/(sqrt(6)2/5)=5/(2 sqrt(6))

L'=gamma*L = 12 * 5/2sqrt(6) = 30/sqrt(6)=5sqrt(6)sqrt(6)/sqrt(6)=5sqrt(6)

L'/2 = sqrt(6)*5/2

At t=5s, v=c/5, x=-5cs, g=gamma
t’_left = g (5s - xc/(5c^2)) = g(5s + 5cs/5c) = g(5s+1s) = 5/2sqrt(6) * 6s = 15/sqrt(6) = sqrt(6)*5/2

At t=7.5s, v=c/5, x=7.5cs, g=gamma
t’_right = g (7.5s – xc/(5c^2)) = g(7.5s – 7.5cs/5c) = g(7.5s-1.5s) = 5/2sqrt(6) * 6s = 15/sqrt(6) = sqrt(6)*5/2

t'_left = t'_right = t'

Distance over time in both directions:
L'/(2*t') = sqrt(6)*5/(2 * sqrt(6)*5/2) = sqrt(6)*5/sqrt(6)*5 = c

This is expected result as per SR.




I'll leave this part for the review now and I will continue with the issues later.
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Old 4th September 2019, 06:28 AM   #239
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Originally Posted by wea View Post
can you please explain that to me? the mathematical dependence of time from distance (?) will suffice


That's where the clock desynchronization comes from.
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Old 4th September 2019, 06:38 AM   #240
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Originally Posted by halleyscomet View Post
You need one.
Only if you show me what I did wrong so far.
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