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

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Old 25th September 2019, 09:30 PM   #481
Robin
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Originally Posted by SDG View Post
Here is the math answer:
https://i.imgur.com/MFhraSZ.png?1

Time t is defined by the left side, time dilation.

Time t is defined by the right side as t=t'/gamma + (v/c^2)x, the simultaneity.

We have two equations for t, which on is correct?
... and they give two different t values for one t'.
... therefore the contradiction.
SDG
Take the one on the left for both.

Going from platform to train v=c/5.

Going from train to platform v=-c/5

Same equation.
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Old 25th September 2019, 09:39 PM   #482
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Here, I have used the same equation each time, just copying and pasting and altering the value of v:



So, for example I have set t=6 and x=0. I do a transform each way and get back my original 6 s

I don't see the problem.
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Old 25th September 2019, 09:42 PM   #483
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Originally Posted by Robin View Post
Take the one on the left for both.

Going from platform to train v=c/5.

Going from train to platform v=-c/5

Same equation.
x'=0 we are left with time.
How is post #461 coming?
SDG
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Old 25th September 2019, 09:45 PM   #484
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Originally Posted by Robin View Post
Here, I have used the same equation each time, just copying and pasting and altering the value of v:

https://robinsrevision.files.wordpre...ge-6.png?w=401

So, for example I have set t=6 and x=0. I do a transform each way and get back my original 6 s

I don't see the problem.
You are saying that the time in moving frame is going faster and not slower, correct?
SDG

Last edited by SDG; 25th September 2019 at 09:46 PM.
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Old 25th September 2019, 09:48 PM   #485
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In post 461, here are my calculations, someone correct me if I am wrong:



So in the train frame, the time that the light reaches the end of the rod is 6.73609679
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Old 25th September 2019, 09:50 PM   #486
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Originally Posted by Robin View Post
In post 461, here are my calculations, someone correct me if I am wrong:

https://robinsrevision.files.wordpre...ge-7.png?w=433

So in the train frame, the time that the light reaches the end of the rod is 6.73609679
You have the same problem, you are claiming that the time is moving faster in the moving frame.
The time is supposed to tick slower in the moving frame.
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Old 25th September 2019, 10:18 PM   #487
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Originally Posted by SDG View Post
You are saying that the time in moving frame is going faster and not slower, correct?
SDG
There is no absolute time so you can't say that one is going faster or slower than the other. Time passes at the same rate in each frame.

Here is my understanding, and again, anyone can correct me if I am wrong.

Say, in the platform frame, you pick a spot on the platform and have one event A at t=0 and another event B at t=1

On the train frame a little more than a second (about 1.02s) will have passed between the events

Say, in the train frame, you pick a spot on the train and have one event C at t=0 and another event D at t=1

On the platform frame, a little more than a second (about 1.02s) will have passed between events C and D.
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Old 25th September 2019, 10:19 PM   #488
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Originally Posted by SDG View Post
You have the same problem, you are claiming that the time is moving faster in the moving frame.
The time is supposed to tick slower in the moving frame.
SDG
Again, neither can be considered the moving frame since there is no absolute position.
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Old 25th September 2019, 10:22 PM   #489
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Originally Posted by SDG View Post
x'=0 we are left with time.
How is post #461 coming?
SDG
If x' is zero and t is not zero and v is not zero than x cannot have been zero. So we must have started with more than just time.
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Old 25th September 2019, 10:25 PM   #490
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Again, I am just a beginner at this, my calculations may be wrong.

But you are doing half a LT in each case and keeping x and x' constantly at zero.

Mathematically that does not make sense.
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Old 25th September 2019, 10:27 PM   #491
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Originally Posted by Robin View Post
There is no absolute time so you can't say that one is going faster or slower than the other. Time passes at the same rate in each frame.

Here is my understanding, and again, anyone can correct me if I am wrong.

Say, in the platform frame, you pick a spot on the platform and have one event A at t=0 and another event B at t=1

On the train frame a little more than a second (about 1.02s) will have passed between the events

Say, in the train frame, you pick a spot on the train and have one event C at t=0 and another event D at t=1

On the platform frame, a little more than a second (about 1.02s) will have passed between events C and D.
What you are saying cannot be reconciled with the text book from the post #387.
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Old 25th September 2019, 10:29 PM   #492
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Originally Posted by SDG View Post
You have the same problem, you are claiming that the time is moving faster in the moving frame.
The time is supposed to tick slower in the moving frame.
SDG
Can you tell me what you think the time is on the train when the light reaches the end of the rod?
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Old 25th September 2019, 10:31 PM   #493
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Originally Posted by SDG View Post
What you are saying cannot be reconciled with the text book from the post #387.
SDG
Why not?
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Old 25th September 2019, 10:40 PM   #494
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Originally Posted by SDG View Post
What you are saying cannot be reconciled with the text book from the post #387.
SDG
The textbook is going from the platform frame and using two events on the train, right?

Whereas I had a platform frame observer considering two events on the platform.

So I don't see the inconsistency
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Old 25th September 2019, 10:42 PM   #495
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I have the duration on the train transforming back to duration on the platform by delta t * gamma, so it seems perfectly consistent.
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Old 25th September 2019, 10:43 PM   #496
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Originally Posted by Robin View Post
Again, I am just a beginner at this, my calculations may be wrong.

But you are doing half a LT in each case and keeping x and x' constantly at zero.

Mathematically that does not make sense.
The post #250 shows the transition from the full blown calculations done before the post #250 to the simplified one.
The simplified calculation is correct.
SDG
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Old 25th September 2019, 10:45 PM   #497
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Originally Posted by Robin View Post
The textbook is going from the platform frame and using two events on the train, right?

Whereas I had a platform frame observer considering two events on the platform.

So I don't see the inconsistency
You say: Time passes at the same rate in each frame
The textbook shows what is time dilation - not the same rate in each frame.
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Old 25th September 2019, 10:48 PM   #498
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Time passes at the same rate in each frame relative to the observer in that frame.

Time passes at a slower rate in each frame relative to the observer in the other frame.

That's why it's called the theory of relativity.
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Old 25th September 2019, 10:51 PM   #499
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Here is the table I created. I set x=1 and did a LT for t=0,1,2,3 in each case:
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Old 25th September 2019, 10:53 PM   #500
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Originally Posted by SDG View Post
You say: Time passes at the same rate in each frame
The textbook shows what is time dilation - not the same rate in each frame.
SDG
Again, there is no such thing as absolute time.

Time passes at the same rate in each from. The duration between two events in one frame will differ from the duration between those two events in another frame.
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Old 25th September 2019, 11:03 PM   #501
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Originally Posted by SDG View Post
You say: Time passes at the same rate in each frame
The textbook shows what is time dilation - not the same rate in each frame.
SDG
Also, the calculations in my table match what the textbook says, so you can't claim I am saying anything that disagrees with it.

Try those calculations yourself.
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Old 26th September 2019, 03:09 AM   #502
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Originally Posted by SDG View Post
You say: Time passes at the same rate in each frame
The textbook shows what is time dilation - not the same rate in each frame.
SDG
I believe your problem is that you are thinking of the platform frame as fixed and static, it's the mistake many people make.

There's no such thing as a fixed or static frame. Every observer sees their own frame as being normal.

As far as the observers on the train are concerned they are stationary, and their clocks are ticking at the correct rate - it's the platform that is moving and the platform's clocks are ticking at a slower rate.

As far as the observers on the platform are concerned they are stationary, and their clocks are ticking at the correct rate - it's the train that is moving and the train's clocks are ticking at a slower rate.
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Old 26th September 2019, 06:00 AM   #503
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Originally Posted by SDG View Post
Really? What is different between the two bold parts in describing the thought experiments.
I did exactly the same thing as the text book. My thought experiment is clearly described.
SDG

The text book thought experiment you posted has the light pulse traveling across the width of the train and back. The events of the light pulse reaching the far side of the train and then being reflected back to the near side of the train therefore all happen at x=0 in the train frame. This simplifies the Lorentz transformation of these events to the platform frame because the xv term is zero.

In your thought experiment, the light pulse must travel in the x direction, and the x coordinate of your subsequent defined events does not remain zero in either frame. Yet you apply the simplified transformation (t = lambda*t') that can only be correct when x=0. That is an error.

If you continue to make excuses to try to justify that error rather than correct it, you'll continue to be confused.
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Old 26th September 2019, 06:06 AM   #504
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Originally Posted by SDG View Post
Another modification of our thought experiment, now to the left.

I'm going to ignore your new thought experiment unless and until you respond to my assessment of your previous thought experiment in post #349. If you're not paying attention to the answers, why should I or anyone bother to post them?
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Old 26th September 2019, 06:35 AM   #505
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In general it seems to be the case that if two events in a frame occur at the same place in that frame then the duration between them will transform to another frame as the product of t and the Lorentz factor.
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Old 26th September 2019, 07:22 AM   #506
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Originally Posted by Robin View Post
In general it seems to be the case that if two events in a frame occur at the same place in that frame then the duration between them will transform to another frame as the product of t and the Lorentz factor.

Yes, or even if they're at different y' and/or z', as long as they're at the same x', as in the textbook thought experiment SDG posted. If delta x' is zero (and of course, v isn't changing), everything cancels out and t' = gamma * t.

That's basically what's going on with the general statements about the rate of a clock in a different frame, e.g. "the clock in the moving frame runs slower." It doesn't matter where the clock is, as long as it's stationary in the frame referenced.

But, note that that's not the case in SDG's thought experiments involving the movement of light pulses being measured parallel to x or x'.
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Old 26th September 2019, 01:42 PM   #507
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Originally Posted by SDG View Post
The relativity of simultaneity says that t'=6.25s of the platform time is supposed to be train time of t=6.1237s.
The time dilation says that t'=6.25s of the platform time is supposed to be train time of t=6.3788s.
Wrongly stated, SDG.
Relativity of simultaneity applies to events, not time. Time dilation applies to time intervals, not time. If you stated an event and stated a time interval then you have the issue that relativity of simultaneity is not time dilation. Getting different values would not be a surprise to anyone who has learned about SR.
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Old 26th September 2019, 01:56 PM   #508
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Thumbs down A "two equations for t" lie when there is 1 equation for t

Originally Posted by SDG View Post
Time t is defined by the left side, time dilation.
...
Wrong, SDG.
This is the real Lorentz transformation. Time t is defined in the words you left out. Time t is defined as the time in in one frame with t' defined as the time in the other frame.
Time t is transformed from the left side by math that is not time dilation (note the presence of x that you highlight!).
Time t' is transformed from the left side by math that is also not time dilation (note the presence of x that you highlight!). It is definitely not your "simultaneity" (two events happening at the same time).

Everyone knows that both equation are correct.

27 September 2019 SDG: A "two equations for t" lie when there is 1 equation for t.
There is only 1 equation that transforms t' and x' to t.

Last edited by Reality Check; 26th September 2019 at 02:00 PM.
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Old 26th September 2019, 02:03 PM   #509
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Originally Posted by SDG View Post
x'=0 we are left with time.
Well duh, SDG, and when x' is not 0, we are not left with time !
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Old 26th September 2019, 02:13 PM   #510
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Exclamation Post #250 is abysmally ignorant because it asks about time dilation without clocks

Originally Posted by SDG View Post
The post #250 ...
27 September 2019 SDG: Post #250 is abysmally ignorant because it asks about time dilation when there are no clocks in your example !

Time dilation does not apply in your example because you have no clocks. The Lorentz transform does not have time intervals and so has no time dilation. Calculations that have a Lorentz factor in them are not a time dilation.
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Old 26th September 2019, 02:22 PM   #511
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  1. 30 August 2019 SDG: Note the absence of clocks in the thought experiments for relativity of simultaneity.
  2. 5 September 2019 SDG: Does not understand that Einstein is applying "the principle of constancy of the speed of light" in his 1905 paper.
  3. 5 September 2019 SDG: Three rather incoherent posts on a bad "thought experiment" with invalid physics
  4. 5 September 2019 SDG: An ignorant "Where is time dilation in all of this" question (he has no clocks!).
  5. 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!
  6. 16 September 2018 SDG: SR needs a "hierarchy between the frames" delusion.
  7. 17 September 2019 SDG: An ignorant question because SR time dilation is really reciprocal.
  8. 18 September 2019 SDG: Time on the platform does not represents 2 times on the train.
  9. 18 September 2019 SDG: Abysmal ignorance about SR( Lorentz transformation and inertial frames).
  10. 20 September 2019 SDG: "Look at this text book" evidence of denying textbook physics!
  11. 20 September 2019 SDG: Persistent ignorance of SR where constant c is a postulate?
  12. 26 September 2019 SDG: A "I showed through the thought experiment that the isotropy of the one way light speed cannot be true" lie (ignorance and opinion show nothing).
  13. 26 September 2019 SDG: An irrelevant question about ever changing thought experiments to waste our time yet again.
  14. 26 September 2019 SDG: A dumb question when the post he replied to states the mistake !
  15. 26 September 2019 SDG: Ignorant "reciprocity" and "proper time intervals" questions about textbook SR.
  16. 26 September 2019 SDG: More ignorance - proper length is a length measured in the frame, i.e. L or L' by definition.
  17. 27 September 2019 SDG: A "two equations for t" lie when there is 1 equation for t.
  18. 27 September 2019 SDG: Again: Post #250 is abysmally ignorant because it asks about time dilation when there are no clocks in your example !
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Old 26th September 2019, 08:44 PM   #512
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Originally Posted by Robin View Post
Here is the table I created. I set x=1 and did a LT for t=0,1,2,3 in each case:
https://robinsrevision.files.wordpre...e-10.png?w=452
Let us try the text book example one more time.



The blue arrows represent how the light beam is seen by the grid of platform inertial observers.
The red arrows represent how the light beam is seen by the grid of train inertial observers.
Do you agree?
SDG
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Old 26th September 2019, 08:48 PM   #513
SDG
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Originally Posted by wollery View Post
I believe your problem is that you are thinking of the platform frame as fixed and static, it's the mistake many people make.

There's no such thing as a fixed or static frame. Every observer sees their own frame as being normal.

As far as the observers on the train are concerned they are stationary, and their clocks are ticking at the correct rate - it's the platform that is moving and the platform's clocks are ticking at a slower rate.

As far as the observers on the platform are concerned they are stationary, and their clocks are ticking at the correct rate - it's the train that is moving and the train's clocks are ticking at a slower rate.
Agreed, this is called the reciprocity.
Does it mean that the inertial observers cannot agree on their respective time intervals then?
How they can agree on ds/dt and dv/dt?
SDG
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Old 26th September 2019, 08:57 PM   #514
SDG
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Originally Posted by Myriad View Post
The text book thought experiment you posted has the light pulse traveling across the width of the train and back. The events of the light pulse reaching the far side of the train and then being reflected back to the near side of the train therefore all happen at x=0 in the train frame. This simplifies the Lorentz transformation of these events to the platform frame because the xv term is zero.

In your thought experiment, the light pulse must travel in the x direction, and the x coordinate of your subsequent defined events does not remain zero in either frame. Yet you apply the simplified transformation (t = lambda*t') that can only be correct when x=0. That is an error.

If you continue to make excuses to try to justify that error rather than correct it, you'll continue to be confused.
I have chosen to do the thought experiment along the x, x' axes because Einstein did his 1905 derivation that way.
The time dilation result is the same.
There is no error in calculating a proper time interval along the world line at x=0 or x'=0 position.
To show the relativity problem with the normal (90 degree) direction of the light beam is even easier.
Give me a few posts to present it. The post #512 is the first one. Do you agree what is shown on the presented diagram?
SDG

Edit: The bold part
This cannot be error. If the relativity does not work for x=0 then it is no good.
The relativity has to be bulletproof, if not then it has to be scraped.

Last edited by SDG; 26th September 2019 at 09:59 PM.
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Old 26th September 2019, 09:16 PM   #515
Reality Check
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Exclamation Back to "textbook example" idiocy that cannot show any problem with SR

Originally Posted by SDG View Post
Let us try the text book example one more time.
27 September 2019 SDG: Back to "textbook example" idiocy that cannot show any problem with SR!

Nothing from an SR textbook will show that SR is wrong. Repeating his persistent ignorance of SR will result in the same answers. We will probably get the same old idiocy of questions on "time dilation " and "reciprocity" and "simultaneity" with the same weeks old fantasy that his imagination makes SR wrong.

18 posts of ignorance, fantasies and a few lies from 30 August to 27 September 2019 (and growing!)

Last edited by Reality Check; 26th September 2019 at 09:25 PM.
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Old 26th September 2019, 09:35 PM   #516
SDG
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Originally Posted by Myriad View Post
There are three events defined in your thought experiment: the emission of the light flash at the origin at t=t'=x=x'=0, the arrival of the light at the front of the train, and the arrival of the light at the end of the bar on the platform.

In the platform frame, the front of the train is 6cs from the origin when the light flashes, the end of the bar is 6.25cs from the origin, and the train is moving at v = c/5.

In the train frame, the front of the train is 6.124cs from the origin when the light flashes, the end of the bar is 6.124cs from the origin, and the bar is moving at v = -c/5.

In the platform frame, the light reaches the end of the bar at 6.25s and catches up with the front of the train at 7.5s.

In the train frame, the light and the end of the bar converge at 5.103s and the light reaches the front of the train at 6.124s.

In the platform frame, no event defined in the thought experiment takes place at 5.103s or 6.124s.


When the light hits the LE of the train car it is in 5s of the platform grid inertial observers proper time.
The time dilation interval to the train frame is 5.103s.
See how the simultaneity lines are drawn in the space time diagrams.
https://www1.phys.vt.edu/~takeuchi/r...section11.html
The 5.103s and 6.124s are defined on ct world line that represents the train frame.

Quote:
In the train frame, no event defined in the thought experiment takes place at 6.25s or 7.5s.
Just have a look at the diagram. The 6.25s and 7.5s are defined on ct' world line that represents the platform frame because ct as the train world line is not moving.
What is the problem?

Quote:
No event defined in the thought experiment takes place in either frame at 6.379s.
The 6.379s is for the extended experiment when there is 6.25cs green rod to the right on the platform and the grid of the train inertial observers observers the platform light traveling along the green rod.
The 6.379s is time dilated interval in the train frame.
Please, have a look at the Virginia Tech link how time dilation is determined through the simultaneity lines.
https://www1.phys.vt.edu/~takeuchi/r...section12.html

Quote:
When you apply the Lorentz Transforms correctly to the time intervals of the events in either frame, you can derive the time intervals of those same events in the other frame. Those equations incorporate time dilation (the factor gamma) and also necessarily depend upon the relative velocity.

Merely multiplying some time interval by gamma is not a correct Lorentz Transform in these cases, as it fails to take the relative velocity between the train and platform into account.
As mentioned before what is the result of LT when x=0 and x'=0 are considered? LT has to work for this instance as well.
SDG
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Old 26th September 2019, 10:17 PM   #517
SDG
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Originally Posted by Robin View Post
In general it seems to be the case that if two events in a frame occur at the same place in that frame then the duration between them will transform to another frame as the product of t and the Lorentz factor.
This is excellent point.
The interval between 5s and 7.5s of the platform frame at x=0 should be transformed to the train frame as some kind of interval as well with gamma involved.
The platform interval has no corresponding interval in the train frame though. How is this possible?
What relativity is saying is this: the cavity light clock is ticking in the platform frame between 5s and 7.5s and the train grid of the inertial observers does not see it because it has time frozen in a now moment across the board.
How is this supposed to work?
SDG
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Old 26th September 2019, 10:47 PM   #518
Robin
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Originally Posted by SDG View Post
The interval between 5s and 7.5s of the platform frame at x=0 should be transformed to the train frame as some kind of interval as well with gamma involved.
The platform interval has no corresponding interval in the train frame though. How is this possible?
I am not sure what you mean. Following is just that interval and the corresponding interval in the train frame:

I don't know what it has to do with any of your arguments as you don't define any events at x=0 at those times.

Quote:
What relativity is saying is this: the cavity light clock is ticking in the platform frame between 5s and 7.5s and the train grid of the inertial observers does not see it because it has time frozen in a now moment across the board.
How is this supposed to work?
SDG
I don't see how relativity is saying anything like that.
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"

Last edited by Robin; 26th September 2019 at 10:48 PM.
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Old 26th September 2019, 10:59 PM   #519
Robin
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Originally Posted by SDG View Post
As mentioned before what is the result of LT when x=0 and x'=0 are considered? LT has to work for this instance as well.
SDG
It wouldn't be possible for both x=0 and x'=0 in a LT unless v=0 as well, in which case it is not really another frame, or if t=0.

The LT works fine in both those cases.

In every other case if x is zero then x' will be non-zero and vice versa.
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax"

Last edited by Robin; 26th September 2019 at 11:18 PM.
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Old 26th September 2019, 11:12 PM   #520
Elagabalus
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Originally Posted by SDG View Post
This is excellent point.
The interval between 5s and 7.5s of the platform frame at x=0 should be transformed to the train frame as some kind of interval as well with gamma involved.
The platform interval has no corresponding interval in the train frame though. How is this possible?
What relativity is saying is this: the cavity light clock is ticking in the platform frame between 5s and 7.5s and the train grid of the inertial observers does not see it because it has time frozen in a now moment across the board.
How is this supposed to work?
SDG
Dude, go bother someone else over on cluesforum with this horse ****.
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