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

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Old 4th September 2019, 06:50 AM   #241
Myriad
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Originally Posted by SDG View Post
The platform observer sees the light moving at c+v and c-v in the train frame...

No observer sees/measures light moving at any speed other than c. (Disregarding the effects of having air instead of vacuum.)

The platform observer might imagine that he, or the train observer, might measure the speed of the light as being affected by the speed and direction of the train, such as c+v or c-v. But any such imagining would be in error. The measured speed will always be c.
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Old 4th September 2019, 07:05 AM   #242
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Originally Posted by Myriad View Post
No observer sees/measures light moving at any speed other than c. (Disregarding the effects of having air instead of vacuum.)

The platform observer might imagine that he, or the train observer, might measure the speed of the light as being affected by the speed and direction of the train, such as c+v or c-v. But any such imagining would be in error. The measured speed will always be c.

From original - Einstein's 1905 paper:



Please, read his paper before talking about the error.
You are going against Einstein's derivation here, seriously?
SDG
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Old 4th September 2019, 07:21 AM   #243
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Originally Posted by Myriad View Post
No observer sees/measures light moving at any speed other than c. (Disregarding the effects of having air instead of vacuum.)

The platform observer might imagine that he, or the train observer, might measure the speed of the light as being affected by the speed and direction of the train, such as c+v or c-v. But any such imagining would be in error. The measured speed will always be c.

I will add, the c+v and c-v observation is crucial to the derivation.
That's the reason, in addition to the second postulate (constancy of c), why the light crosses 12cs in train frame and 12.5cs in the platform frame as it is seen/observed from the platform frame.
Please, check the figures 1-3.
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Old 4th September 2019, 09:04 AM   #244
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Originally Posted by SDG View Post
I will add, the c+v and c-v observation is crucial to the derivation.
That's the reason, in addition to the second postulate (constancy of c), why the light crosses 12cs in train frame and 12.5cs in the platform frame as it is seen/observed from the platform frame.
Please, check the figures 1-3.
SDG
Look, SDG, you are doing this all wrong. IF you have found a flaw in Einstein's theory of relativity, the last thing you want to do is blabber it all over some public internet forum. What you must do is publish in a recognized, peer reviewed scientific magazine. And then sit back and wait for fame and fortune.

You see, in the (unlikely) instance that you are right, anyone who happens to read this thread can steal your idea, publish it before you, and take all the honour.

Hans
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Old 4th September 2019, 09:12 AM   #245
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Originally Posted by MRC_Hans View Post
You see, in the (unlikely) instance that you are right, anyone who happens to read this thread can steal your idea, publish it before you, and take all the honour.
God DAMN it man! Don't you realize that's why I'm ON this forum????

Don't try to publish SDG. Stay right here talking to US about your ideas, in great detail. Exquisite detail. Leave nothing out.

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Old 4th September 2019, 09:17 AM   #246
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Originally Posted by MRC_Hans View Post
Look, SDG, you are doing this all wrong. IF you have found a flaw in Einstein's theory of relativity, the last thing you want to do is blabber it all over some public internet forum. What you must do is publish in a recognized, peer reviewed scientific magazine. And then sit back and wait for fame and fortune.

You see, in the (unlikely) instance that you are right, anyone who happens to read this thread can steal your idea, publish it before you, and take all the honour.

Hans
Stealing cannot happen. These postings here are the proof.
I would take them to court and you would be my witness, wouldn't you?
All in good spirit

Joking aside, do you see any problems in what I posted so far?
SDG

Last edited by SDG; 4th September 2019 at 09:28 AM.
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Old 4th September 2019, 09:20 AM   #247
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Originally Posted by halleyscomet View Post
God DAMN it man! Don't you realize that's why I'm ON this forum????

Don't try to publish SDG. Stay right here talking to US about your ideas, in great detail. Exquisite detail. Leave nothing out.

https://i.imgur.com/iKlcYeL.gif
I am watching you, Halley's Comet!!
SDG
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Old 4th September 2019, 09:45 AM   #248
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Originally Posted by SDG View Post
I am watching you, Halley's Comet!!
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 4th September 2019, 10:03 AM   #249
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Originally Posted by SDG View Post
do you see any problems in what I posted so far?
Myriad already told you. All observers always measure the speed of light to be c. That's the second postulate.
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Old 4th September 2019, 10:36 AM   #250
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Question 1: Where is time dilation in all of this?

We started with half the train Lorentz contracted length 6cs in platform frame.
We got the proper length L' = gamma * L of the train frame.
We got the proper time period along the train world line t'=sqrt(6)*5/2s by using LT 5s, 7.5s for time and -5cs, 7.5cs for clock desynchronization.
This translates to time dilation interval t = gamma * t' = (5/(2 sqrt(6))) * (sqrt(6)*5/2) = 25/4 = 6.25s of the platform world line.
I'll emphasize, the proper time interval along the platform world line.

This is exactly the 1/2 of the distance the light travelled in platform frame 12.5cs/2=6.25cs !!!
In other words Lorentz contracted length multiplied by gamma^2 gives us the time dilated interval in the same reference frame.
It is 'simple/straightforward', the simplicity and symmetry of LT is beautiful, I mean it.

More questions are coming.
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Old 4th September 2019, 11:17 AM   #251
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Originally Posted by Pixel42 View Post
Myriad already told you. All observers always measure the speed of light to be c. That's the second postulate.

Please, tell me, did the light crossed the same distance as observed from the platform frame?



Are the blue light beams equal in length to the red light beams?
No!!! In order to show that c is the same in both frames the mathematical gymnastics is required as shown on the previous page.
And no for the measurement as well.
I am showing one way example.
There is no experiment that measured one way speed of light.

Quote:
Experiments that attempted to directly probe the one-way speed of light independent of synchronization have been proposed, but none has succeeded in doing so.
Quote:
In general, it was shown that these experiments are consistent with anisotropic one-way light speed as long as the two-way light speed is isotropic.
https://en.wikipedia.org/wiki/One-way_speed_of_light

I'd be really interested if you can show me a one way speed of light measurement experiment.
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Old 4th September 2019, 11:24 AM   #252
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Hans, Myriad, Pixel, Halley's Comet, Wea, Reality Check, ... and all!
Thanks, keep coming with questions.
These coming posts/pages are going to be good for others interested in SR.
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Old 4th September 2019, 11:27 AM   #253
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Originally Posted by SDG View Post
From original - Einstein's 1905 paper:

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

Please, read his paper before talking about the error.
You are going against Einstein's derivation here, seriously?
SDG

I don't see anything wrong with Einstein's math.

I do see a wrong statement in your claims, though: "The platform observer sees the light moving at c+v and c-v in the train frame..."

The expressions (x' / (c - v)) and (x' / (c + v)) in the equations you quoted represent intervals of time, not the speed of the light pulse (which of course in all cases is represented as c). They're different intervals of time, expressing the fact that the train platform observer measures the time the light pulse takes to go from its origin in the center of the train to the reflector at the front of the train as greater than the time it takes to return from the reflector to the center of the train.

The platform observer sees unequal time intervals for the light to travel in each direction, NOT because he sees the light traveling at different speeds but because he sees the light traveling a different distance to the reflector than back from it.
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Old 4th September 2019, 11:45 AM   #254
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Originally Posted by SDG View Post
Please, tell me, did the light crossed the same distance as observed from the platform frame?

Yes. Because all the light pulses were emitted at the same time as one another, and in the same place, and are being observed from the same inertial reference frame (the platform's), they would all be measured from that same reference frame as having crossed the same distance at any future time.

The way you drew your red lines is inconsistent with this fact, and is therefore wrong. How you choose to draw lines on a drawing does not affect the behavior of light in nature.
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Old 4th September 2019, 11:47 AM   #255
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Originally Posted by SDG View Post
These coming posts/pages are going to be good for others interested in SR.
I doubt many people interested in SR want to read multiple posts in which fundamental misunderstandings of it are patiently corrected.

Just do the course I linked.
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Old 4th September 2019, 02:18 PM   #256
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Exclamation Einstein is applying "the principle of constancy of the speed of light"

Originally Posted by SDG View Post
From original - Einstein's 1905 paper:
There is no error other than you showing no sign of wanting to learn about special relativity, SDG.
Myriad wrote: No observer sees/measures light moving at any speed other than c. [in vacuum and inertial observers]
5 September 2019 SDG: Does not understand that Einstein is applying "the principle of constancy of the speed of light" in his 1905 paper.

This is basic SR. SR has the postulate confirmed by 114 years of experiments that the speed of light in vacuum is the same for inertial observers.
30 August 2019 SDG: Note the absence of clocks in the thought experiments for relativity of simultaneity.
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Old 4th September 2019, 02:20 PM   #257
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Originally Posted by SDG View Post
Well known Einstein's train embankment thought experiment ....
You are still ignorant about Einstein's train embankment thought experiment:
30 August 2019 SDG: Note the absence of clocks in the thought experiments for relativity of simultaneity.
No clock in the thought experiment. No time dilation in the thought experiment.
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Old 4th September 2019, 02:29 PM   #258
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Thumbs down Three rather incoherent posts on a bad "thought experiment" with invalid physics

Originally Posted by SDG View Post
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....]
5 September 2019 SDG: Three rather incoherent posts on a bad "thought experiment" with invalid physics.
As soon as we see "distance travelled by the light at c+v and c-v" when light always travels at c we know that you are using invalid physics, SDG.

We know special relativity as can anyone who reads Wikipedia, SDG! SR has the postulate confirmed by 114 years of experiments that the speed of light in vacuum is the same for inertial observers.

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Old 4th September 2019, 02:40 PM   #259
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Exclamation An ignorant "Where is time dilation in all of this" question

Originally Posted by SDG View Post
Question 1: Where is time dilation in all of this?
5 September 2019 SDG: An ignorant "Where is time dilation in all of this" question.
It is your thought experiment. where you ignore time dilation .! Add some clocks and apply SR to get time dilation.

More ignorant questions coming?
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Old 4th September 2019, 02:53 PM   #260
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Thumbs down Ignores the content of [B]Pixel42[/B]'s post about [B]Myriad[/B]'s post stating basic

Originally Posted by SDG View Post
Please, tell me, did the light crossed the same distance as observed from the platform frame?
...
5 September 2019 SDG: Ignores the content of Pixel42's post about Myriad's post stating the second postulate of SR as confirmed by 114 years of experiments!

"There is no experiment that measured one way speed of light." ignorance. One-way speed of light
Quote:
Experiments that attempted to directly probe the one-way speed of light independent of synchronization have been proposed, but none has succeeded in doing so
(my emphasis added)
There are experiments that have measured the one way speed of light with a form of synchronization. The first was in 1676! Ole RÝmer measured the speed of light using Io, a moon of Jupiter. Modern analysis showed that this used the Jupiter system as a "slowly-transported clock to measure the light transit times".

What is the experimental basis of Special Relativity? (3.2 One-Way Tests of Light-Speed Isotropy)
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Old 4th September 2019, 02:56 PM   #261
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SDG, they go over this here:

https://youtu.be/BFLUa0ciMjw?t=372

They even use a light clock and and a conventional (analog) clock. And their diagrams are much easier to understand than yours.
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Old 5th September 2019, 12:40 PM   #262
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Originally Posted by SDG View Post
Stealing cannot happen. These postings here are the proof.
I would take them to court and you would be my witness, wouldn't you?
All in good spirit
An idea does not belong to whomever gets it first, but to whomever publishes it first.

Quote:
Joking aside, do you see any problems in what I posted so far?
SDG
Several people have already pointed out the faults. No reason for me to take the trouble.

Hans
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Old 11th September 2019, 09:43 AM   #263
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Originally Posted by MRC_Hans View Post
An idea does not belong to whomever gets it first, but to whomever publishes it first.



Several people have already pointed out the faults. No reason for me to take the trouble.

Hans
Hi Hans,
I have a paper. Can you help to find someone who can help with endorsement?
https://arxiv.org/help/endorsement
SDG
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Old 11th September 2019, 10:07 AM   #264
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Originally Posted by Myriad View Post
I don't see anything wrong with Einstein's math.

I do see a wrong statement in your claims, though: "The platform observer sees the light moving at c+v and c-v in the train frame..."

The expressions (x' / (c - v)) and (x' / (c + v)) in the equations you quoted represent intervals of time, not the speed of the light pulse (which of course in all cases is represented as c). They're different intervals of time, expressing the fact that the train platform observer measures the time the light pulse takes to go from its origin in the center of the train to the reflector at the front of the train as greater than the time it takes to return from the reflector to the center of the train.

The platform observer sees unequal time intervals for the light to travel in each direction, NOT because he sees the light traveling at different speeds but because he sees the light traveling a different distance to the reflector than back from it.
Why did Einstein use c+v and c-v in his derivation?
What does it represent?
SDG
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Old 11th September 2019, 10:14 AM   #265
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Originally Posted by Myriad View Post
Yes. Because all the light pulses were emitted at the same time as one another, and in the same place, and are being observed from the same inertial reference frame (the platform's), they would all be measured from that same reference frame as having crossed the same distance at any future time.

The way you drew your red lines is inconsistent with this fact, and is therefore wrong. How you choose to draw lines on a drawing does not affect the behavior of light in nature.
OK, this is my version:


Please, present your version of the lines/arrows so we can compare.
How we can capture the fact that origin x'=0 moves in the platform frame with passing time?
Thanks,
SDG
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Old 11th September 2019, 01:34 PM   #266
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Originally Posted by SDG View Post
Why did Einstein use c+v and c-v in his derivation?
What does it represent?
SDG
Easy: c is the speed of light. v is a speed. c+v is their addition. c-v is their subtraction !

N.B. Einstein knew the postulates of SR because he wrote them. He is not saying that the speed of light changes in his 1905 paper that starts with the constant speed of light postulate. This is explicitly stated in the image you gave from the paper.

ETA: The 1905 paper is available as text: ON THE ELECTRODYNAMICS OF MOVING BODIES. You are looking at "3. Theory of the Transformation of Co-ordinates and Times from a Stationary System to another System in Uniform Motion of Translation Relatively to the Former". Einstein is deriving that transformation which we call the Lorentz transformation (see the end of the section).

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Old 11th September 2019, 04:41 PM   #267
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Originally Posted by SDG View Post
Why did Einstein use c+v and c-v in his derivation?
What does it represent?
SDG

Given a target moving at constant velocity v (less than c) in the same direction as a light pulse moving at velocity c which is converging on it,

c-v

is the rate of change in the distance between the light pulse and the target, as observed from the same inertial reference frame from which v was measured.

Given a target moving at constant velocity v (less than c) in the opposite direction as a light pulse moving at velocity c which is converging on it,

c+v

is the rate of change in the distance between the light pulse and the target, as observed from the same inertial reference frame from which v was measured.


It appears you want to object to "c+v" appearing in an equation because that represents "something moving faster than c" which is impossible. It does not. It represents a distance between two things that is changing faster than c. That's completely possible. Imagine two light rays coming directly toward one another, for instance. The distance between them decreases twice as fast as c.
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Old 12th September 2019, 05:36 AM   #268
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Originally Posted by Myriad View Post
It appears you want to object to "c+v" appearing in an equation because that represents "something moving faster than c" which is impossible. It does not. It represents a distance between two things that is changing faster than c. That's completely possible. Imagine two light rays coming directly toward one another, for instance. The distance between them decreases twice as fast as c.
From an outside observer (just to clarify). From the FoR of either of the light particles they're approaching each other at c; the insight that formed the basis of special relativity.
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Old 12th September 2019, 09:28 AM   #269
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Originally Posted by Myriad View Post
Given a target moving at constant velocity v (less than c) in the same direction as a light pulse moving at velocity c which is converging on it,

c-v

is the rate of change in the distance between the light pulse and the target, as observed from the same inertial reference frame from which v was measured.

Given a target moving at constant velocity v (less than c) in the opposite direction as a light pulse moving at velocity c which is converging on it,

c+v

is the rate of change in the distance between the light pulse and the target, as observed from the same inertial reference frame from which v was measured.


It appears you want to object to "c+v" appearing in an equation because that represents "something moving faster than c" which is impossible. It does not. It represents a distance between two things that is changing faster than c. That's completely possible. Imagine two light rays coming directly toward one another, for instance. The distance between them decreases twice as fast as c.
I am using SR arguments, the Einstein's derivation with c+v and c-v is essential to get the relativity of simultaneity, 5s in one direction and 7.5s in the other direction from the platform frame point of view.
I followed that with the LT calculation how the disagreement of simultaneity does not change the outcome that the light moves with c in the train frame even though the distance, as you point out, is changing at c+v/c-v from the platform frame view because the origin x'=0 is changing in the platform frame while the light propagates.
The light moves at c in the platform frame as well therefore we have 5s, 7.5s in the platform frame.
The light moves at c in both frames in our thought experiment, everything is according the SR.

I have not got to the point of showing the SR problem in the thought experiment yet.
I am looking for an agreement that everything done in the thought experiment is in line with the SR so far.
SDG
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Old 12th September 2019, 11:23 AM   #270
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Originally Posted by SDG View Post
I am using SR arguments, the Einstein's derivation with c+v and c-v is essential to get the relativity of simultaneity, 5s in one direction and 7.5s in the other direction from the platform frame point of view.
I followed that with the LT calculation how the disagreement of simultaneity does not change the outcome that the light moves with c in the train frame even though the distance, as you point out, is changing at c+v/c-v from the platform frame view because the origin x'=0 is changing in the platform frame while the light propagates.
The light moves at c in the platform frame as well therefore we have 5s, 7.5s in the platform frame.
The light moves at c in both frames in our thought experiment, everything is according the SR.

I have not got to the point of showing the SR problem in the thought experiment yet.
I am looking for an agreement that everything done in the thought experiment is in line with the SR so far.
SDG

Einstein's use of c+v and c-v in the equations you referenced refers only to the platform frame.

If by x' you mean the origin of the light pulse, the highlighted statement in your post makes no sense. The location where the light pulse was emitted does not move, in the platform frame. Or in any frame, for that matter, because an event's location cannot change after it's already happened! It's like saying if you shot a gun and hit a target, then mailed the gun to Peoria, you've now hit the target from Peoria.

What's changing in the platform frame is the location of the ends of the train (and therefore, the distances the light pulses travel) by the time the light pulses get there. (In the train frame, those don't change.) In the platform frame, that means the light pulses arrive at the ends of the train at different times. (In the train frame, they arrive at the same time.)
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Old 12th September 2019, 12:46 PM   #271
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Originally Posted by Myriad View Post
Einstein's use of c+v and c-v in the equations you referenced refers only to the platform frame.

If by x' you mean the origin of the light pulse, the highlighted statement in your post makes no sense. The location where the light pulse was emitted does not move, in the platform frame. Or in any frame, for that matter, because an event's location cannot change after it's already happened! It's like saying if you shot a gun and hit a target, then mailed the gun to Peoria, you've now hit the target from Peoria.

What's changing in the platform frame is the location of the ends of the train (and therefore, the distances the light pulses travel) by the time the light pulses get there. (In the train frame, those don't change.) In the platform frame, that means the light pulses arrive at the ends of the train at different times. (In the train frame, they arrive at the same time.)
The position of origin O' of x' changes in x frame with time.
The position of origin O' of x' at t=t'=0 is not changing in x frame with time.
What is the problem?
Do you have a better diagram?
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Old 12th September 2019, 01:06 PM   #272
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Here are a couple of space-time diagrams:




We clearly see where time dilation is as per post #250 going from Lorentz contracted length 6cs in platform frame up to 6.25s.

From the train car point of view.



The disagreement on simultaneity is nicely captured in both diagrams.
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Old 12th September 2019, 01:25 PM   #273
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Originally Posted by SDG View Post
...Do you have a better diagram?
SDG
An animation, perhaps?

Originally Posted by Elagabalus View Post
SDG, they go over this here:

https://youtu.be/BFLUa0ciMjw?t=372

They even use a light clock and and a conventional (analog) clock. And their diagrams are much easier to understand than yours.
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Old 12th September 2019, 03:17 PM   #274
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Originally Posted by Elagabalus View Post
An animation, perhaps?

Well, based on your animation.
What distance did the light travelled in train frame?
Did more time elapse in the train? Is time going faster in the train?
How is animation better?
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Old 12th September 2019, 03:55 PM   #275
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Originally Posted by SDG View Post
Here are a couple of space-time diagrams:

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


We clearly see where time dilation is as per post #250 going from Lorentz contracted length 6cs in platform frame up to 6.25s.

From the train car point of view.

https://i.imgur.com/xgCbC65.png

The disagreement on simultaneity is nicely captured in both diagrams.
SDG

Those diagrams look better to me. Note that, unlike your earlier diagrams, the light paths all start at the origin at t=0 and x=0, and don't shift from there retroactively.

However, the axes labels for the train frame should be reversed, such that x' in the train frame is the horizontal one, and y' in the train frame is the vertical one. The dotted black lines in the second graph should be horizontal just as they are in the first graph (which makes them redundant with the top horizontal black line), and the train observer measures 6 units for both directions.
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Old 12th September 2019, 05:03 PM   #276
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Originally Posted by SDG View Post
Well, based on your animation.
What distance did the light travelled in train frame?
Did more time elapse in the train? Is time going faster in the train?
How is animation better?
SDG

https://i.imgur.com/AVxBNRt.png
The distance isn't specified. However, since the Speed of light is the same for all observers, the train sees the light pulse hit the front and back of the train at the same time. (See your image on the right just an instant before 6:34).

Depends on your reference frame. Keep watching. Goto 21:40

Because (for me) it is more clear on what's happening but YMMV (for instance Goto 11:34).
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Old 12th September 2019, 06:28 PM   #277
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Originally Posted by Myriad View Post
Those diagrams look better to me. Note that, unlike your earlier diagrams, the light paths all start at the origin at t=0 and x=0, and don't shift from there retroactively.

However, the axes labels for the train frame should be reversed, such that x' in the train frame is the horizontal one, and y' in the train frame is the vertical one. The dotted black lines in the second graph should be horizontal just as they are in the first graph (which makes them redundant with the top horizontal black line), and the train observer measures 6 units for both directions.
No to 'dotted black lines in the second graph should be horizontal' comment.
They represent the same now moment for the platform frame point of view, the same way as the diagonal train in the first diagram for the train observer.
The first line - that's how train observer determines 5s for the light hitting the left end from the platform frame point of view.
The second/middle line - that's the time dilation interval 6.25s as calculated for the train proper time 6.123724357s
The third line - that's how train observer determines 7.5s for the light hitting the right end from the platform frame point of view.

No to 'the train observer measures 6 units for both directions' comment.
The train observer measures proper half train car length sqrt(6)*5/2cs=6.123724357cs

I'll repeat what you have might missed:
Quote:
We started with half the train Lorentz contracted length 6cs in platform frame.
We got the proper length L' = gamma * L of the train frame.
We got the proper time period along the train world line t'=sqrt(6)*5/2s by using LT 5s, 7.5s for time and -5cs, 7.5cs for clock desynchronization.
This translates to time dilation interval t = gamma * t' = (5/(2 sqrt(6))) * (sqrt(6)*5/2) = 25/4 = 6.25s of the platform world line.
I'll emphasize, the proper time interval along the platform world line.

This is exactly the 1/2 of the distance the light travelled in platform frame 12.5cs/2=6.25cs !!!
In other words Lorentz contracted length multiplied by gamma^2 gives us the time dilated interval in the same reference frame.
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Old 13th September 2019, 03:44 AM   #278
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Originally Posted by SDG View Post
No to 'dotted black lines in the second graph should be horizontal' comment.
They represent the same now moment for the platform frame point of view, the same way as the diagonal train in the first diagram for the train observer.
The first line - that's how train observer determines 5s for the light hitting the left end from the platform frame point of view.
The second/middle line - that's the time dilation interval 6.25s as calculated for the train proper time 6.123724357s
The third line - that's how train observer determines 7.5s for the light hitting the right end from the platform frame point of view.

You're pointing out that the train observer who knows how fast the train is moving with respect to the platform can use the principles of Special Relativity to calculate what the platform frame observer will observe. If she does it correctly, her predictions of what the platform frame observer will observe will agree with what the platform frame observer actually observes.

But that's jumping several steps ahead. In order to derive and understand those principles of Relativity from such thought experiments, we have to compare what the platform frame observer observes with what the train frame observer observes. (The train observer might not know the platform observer is even there. Or if the train windows are shuttered, the train observer might not be able to measure the speed of the train with respect to the platform. )

What the train frame observer measures is that the light goes equal distances to each end of the train at equal speeds and therefore takes the same amount of time. Do you acknowledge that?

No observer observes any time dilation or length contraction for something that's not moving in their own frame.
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Old 13th September 2019, 06:46 AM   #279
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Originally Posted by Myriad View Post
...
What the train frame observer measures is that the light goes equal distances to each end of the train at equal speeds and therefore takes the same amount of time. Do you acknowledge that?
I do acknowledge that. This is based on the SR only though.
I have already pointed out in post #251 that no experiment proved that.


Quote:
No observer observes any time dilation or length contraction for something that's not moving in their own frame.
Agreed.

Nevertheless, the train moves in the platform frame and the platform frame observers sees the time dilation from 6.123724357s of the proper time along the train world line to 6.25s of the platform proper time along the platform world line.
The train observer has to acknowledge that this is what the platform observers sees for the SR to be any good.
Otherwise the SR is a lost case.
That is the reason those space-time diagrams are correct.
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Old 13th September 2019, 07:58 AM   #280
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Originally Posted by SDG View Post
I do acknowledge that. This is based on the SR only though.
I have already pointed out in post #251 that no experiment proved that.



Agreed.

Nevertheless, the train moves in the platform frame and the platform frame observers sees the time dilation from 6.123724357s of the proper time along the train world line to 6.25s of the platform proper time along the platform world line.
The train observer has to acknowledge that this is what the platform observers sees for the SR to be any good.
Otherwise the SR is a lost case.
That is the reason those space-time diagrams are correct.
SDG

Okay, if you fix the axis labels (x and x', and cy and cy' being reversed in the second diagram), and clearly label the meaning of the dashed black lines and numbers in the second diagram as the train frame observer's calculation based on the equations of S.R. of what the platform frame observer observes rather than what anyone in either frame is actually observing, then those particular diagrams would be correct as far as I can tell.

That being the case... what point are you making with them?
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