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

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Old 14th September 2019, 11:23 AM   #281
SDG
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Question 2: Is SR reciprocity of time dilation real?

Is the reciprocity of time dilation just a question of perspective or the time dilation is real and therefore the reciprocity is a real problem because it leads to contradiction?

We will extend our thought experiment by introducing a 6.25cs rod on the platform as per the next figure. The platform rod (light green) is aligned with x=0. The platform observer sends a light beam along the platform rod at C event when t=tí=0 and x=xí=0. The train conductor observers the light in the platform frame when it hits the end of the rod.



A quick recapitulation of our original calculations.

Platform half the train car length contracted: L=6cs
Proper length: L'=gamma * 6cs=6.1237243569cs
One-way light proper time on the train: t'=6.1237243569s
Proper platform time for t' (time dilation): t=gamma * t'=6.25s

The quick calculation for the light propagation of the platform rod from the train reference frame applying the steps from the above quick recapitulation.
Because the calculation is done from the train frame point of view then the train axes are x, ct, platform axes are xí, ctí.

The contracted rod as seen from the train frame: Lrod=6.1237243569cs
Proper length in the platform frame: L'rod=gamma * 6.1237243569cs = 6.25cs
One-way light proper time in the platform frame: t'=6.25s
Proper train time for t' (time dilation): t=gamma * t'=6.3788795384s




The diagram reveals the Special Relativity logical inconsistency. One platform time interval of 6.25s cannot represent two different times on the train conductorís world line. The relativity of simultaneity requires the value 6.1237243569s but the reciprocity/time dilation demands 6.3788795384s.

The antagonistic relationship between relativity of simultaneity and the reciprocity/time dilation is self-evident from the space time diagram. Two inertial frame observers do not agree on time, they cannot decide who is aging faster based on the reciprocity. The bigger problem is not agreeing on what 6.25s platform time interval represents in the train car frame. If the inertial observers do not agree on time how they can have the same physics? How they can agree on anything above dt (delta time)?
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Old 14th September 2019, 03:43 PM   #282
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Originally Posted by SDG View Post
A quick recapitulation of our original calculations.

Platform half the train car length contracted: L=6cs ok (so the train at rest is actually longer; the platform observer perceives it as contracted to 6 cs)
Proper length: L'=gamma * 6cs=6.1237243569cs ok (so this is the length the conductor would measure his train as, and the platform observer can calculate that from his measurement of the train's length, based on v)
One-way light proper time on the train: t'=6.1237243569s ok
Proper platform time for t' (time dilation): t=gamma * t'=6.25s Absolutely not.

We already know that seeing the train as 6cs long and traveling at c/5, the platform observer sees the light pulse from the origin reach the front end of the train at t = 7.5 cs. That moment in the platform frame is the top black dotted line on your spacetime diagram.

If the conductor thinks t' * gamma is the correct calculation for when the platform observer will measure the light pulse reaching the front of the train, he's making two big mistakes.

First, he's correcting his own measurement for time dilation, but he's not correcting for the fact that the train itself is moving in the platform's frame. Newtonian relativity still applies. Gamma isn't the only possible relevant variable.

Second, he's multiplying by gamma when in this case he should be dividing.

If you measure length of something moving at v relative to you, or an interval of time on a clock that's moving at v relative to you, and you want to know what someone who's moving at v (for whom the clock or ruler is stationary) will measure instead, you multiply by gamma. You see their clock as slower (that is, their time measurements as shorter) and their ruler as shorter, so they will see their own stationary clock as faster (time measurements longer) and their own ruler as longer. That's what's happening in the platform observer's calculation of L', what the conductor would measure, from the platform observer's measurement of L and v. So that calculation was correct.

If you measure length of something stationary in your own frame, or an interval of time on a clock that's stationary in your own frame, and you want to know what someone moving at v relative to you will measure instead, you divide by gamma, because they will see your moving clock as slower (that is, your time measurements as shorter) and your ruler as shorter. That's what is happening in the conductor's calculation of t' for the platform observer from the conductor's measurement of t. Which means the conductor calculated wrong.

If you take the conductor's measurement of t = 6.12 cs and divide it by gamma, you get 6.0 cs. That's the time the platform observer would measure for the light pulse to get from the origin to the point where the front of the train was, by his measurements, at the moment the light pulse began, which reflects that first mistake where he failed to take into account that the train is moving in the platform frame.

I think I'll stop there. You can try making the corresponding correction to the fourth step of your green rod calculations and see what happens. Keep in mind that the platform is moving in the conductor's frame, and that because neither the platform observer nor the conductor is at the end of the rod when the light pulse gets there, and they're in different frames, so there's no reason to expect them to agree about when that event is occurring.
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Old 14th September 2019, 04:05 PM   #283
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Originally Posted by Myriad View Post
Quote:
...
Proper platform time for t' (time dilation): t=gamma * t'=6.25s Absolutely not.
...


t'=6.1237243569s
x'=0 for the conductor in the middle

t=gamma*(t'+0)=6.25s

We cannot continue any discussion till you show me what is wrong with this math!
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Old 14th September 2019, 04:56 PM   #284
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I can wait until you've read the rest of my post.
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Old 14th September 2019, 05:18 PM   #285
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Originally Posted by Myriad View Post
I can wait until you've read the rest of my post.
You have eliminated yourself by showing you do not understand a simple LT calculation.
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Old 14th September 2019, 05:52 PM   #286
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I'm standing on a platform that's 100 meters long. A train comes by that I measure as 100 meters long. The train is going at a high fraction of c, which corresponds to some gamma.

To me, the train looks shorter than it does to the conductor. To the conductor, the platform looks shorter than it does to me.

I know the conductor will measure the train's length to be longer than 100 meters. Specifically, 100 * gamma meters.

I know the conductor will measure the platform's length to be shorter than 100 meters. Specifically, 100 / gamma meters.

The conductor knows that I will measure the platform's length at longer than he measures it. His measurement, xp, is less than 100 meters. My measurement will be xp * gamma meters (which equals 100).

The conductor knows that I will measure the train's length shorter than he measures it. His measurement, xt, is greater than 100 meters. My measurement will be xt / gamma meters (which equals 100).

Originally Posted by SDG View Post
You have eliminated yourself by showing you do not understand a simple LT calculation.
SDG

At least, before eliminating myself, I've explained to everyone else what you're doing wrong by multiplying by gamma in every case.
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Old 14th September 2019, 06:28 PM   #287
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Originally Posted by Myriad View Post
...
At least, before eliminating myself, I've explained to everyone else what you're doing wrong by multiplying by gamma in every case.
Really?
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Old 14th September 2019, 06:31 PM   #288
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Originally Posted by SDG View Post
Really?
SDG

The semaphore flags spell out, "THE CLARITY IS DEVASTATING."

In this case, yeah, it is.
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Old 14th September 2019, 08:53 PM   #289
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Originally Posted by Myriad View Post
The semaphore flags spell out, "THE CLARITY IS DEVASTATING."

In this case, yeah, it is.
What font is for sarcasm? That how I meant 'really?'
You are mistaken and you even don't know it.
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Old 15th September 2019, 06:58 AM   #290
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This is a clarification post to everybody.
Myriad is a smart guy. I read his posts in other threads. They are good!

Nevertheless, what he says is exactly SR contradiction.
He suggests to divide by gamma and it stems from the relativity of simultaneity.
If we do that then the time in the moving train is going faster then the time in the platform frame.
But the SR with LT is clear, we need to multiply by gamma.
This is exactly the contradiction in SR.
The SR does not have a hierarchy between the frames!!!
Everybody, think about the last sentence.
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Old 15th September 2019, 01:44 PM   #291
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Thumbs down SR needs a "hierarchy between the frames" delusion

Originally Posted by SDG View Post
This is a clarification post to everybody. ...
...
All you are making clear, SDG, is a determination to remain ignorant about the textbook physics of SR with a single vague example that you do not understand. An ignorant example will not overturn 114 years of textbook physics taught to millions of students who did understand it. Now you do not cannot understand the arithmetic in posts.

Everyone one else here reads Myriad posts and sees If you take the conductor's measurement of t = 6.12 cs and divide it by gamma, you get 6.0 cs and 100 / gamma meters. This is basic arithmetic. So long as gamma is not zero, we can divide by gamma.

There is no "from the relativity of simultaneity" in Myriad' simple division by gamma posts. You are the one writing about relativity of simultaneity.

16 September 2018 SDG: SR needs a "hierarchy between the frames" delusion.
A main result of physics from theory and experiment over the last more than a century is that there is no "hierarchy" of frames. There is not even a absolute frame of reference. All frames are relative. Anyone who wants to learn about physics can easily find that out.
Inertial frame of reference

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Old 16th September 2019, 12:35 AM   #292
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Originally Posted by SDG View Post
The SR does not have a hierarchy between the frames!!!
Everybody, think about the last sentence.
I have thought about that last sentence, and it makes good sense. Why did you think there was a hierarchy between the frames?

My money is on Myriad.
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Old 16th September 2019, 12:52 AM   #293
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Still struggling to understand why SDG doesn't just do the excellent free online course on Special Relativity I pointed him to. It really does answer all his questions.
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Old 16th September 2019, 01:11 AM   #294
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Originally Posted by Pixel42 View Post
Still struggling to understand why SDG doesn't just do the excellent free online course on Special Relativity I pointed him to. It really does answer all his questions.
As long as he can make people talk to him here ......

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Old 16th September 2019, 02:47 AM   #295
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I’m old enough to still be puzzled by this whole business of presenting new advances in science on Internet forums. In my postdoc days it was really simple: have a good idea, design an experiment to test it, get someone smart to look over the maths with you, write it up, submit the paper to a good quality journal, and then drink coffee while waiting for the Nobel people to get in touch.
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Old 16th September 2019, 04:27 AM   #296
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Originally Posted by steenkh View Post
I have thought about that last sentence, and it makes good sense. Why did you think there was a hierarchy between the frames?

My money is on Myriad.
Based on SR there is no hierarchy.
But if your money is on Myriad then, please, tell me when to divide by gamma and when to multiply by gamma?
Where is the consistency?



When we were analyzing motion of the train from the platform frame we multiplied 6.1237243569 by gamma, the left diagram.
If we go by Myriad then we need to divide by gamma on the right diagram. How come?
How we can assign two train platform time intervals to one time interval on the platform?
Not being consistent with the gamma is an attempt to establish hierarchy.
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Old 16th September 2019, 04:29 AM   #297
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Originally Posted by Pixel42 View Post
Still struggling to understand why SDG doesn't just do the excellent free online course on Special Relativity I pointed him to. It really does answer all his questions.
What did I do wrong in the calculation that I need course?
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Old 16th September 2019, 04:33 AM   #298
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Originally Posted by MRC_Hans View Post
As long as he can make people talk to him here ......

Hans
The only attempt to point out that I am wrong came from Myriad and I showed what's wrong with it.
Where is your contribution?
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Old 16th September 2019, 04:48 AM   #299
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Originally Posted by malbui View Post
Iím old enough to still be puzzled by this whole business of presenting new advances in science on Internet forums. In my postdoc days it was really simple: have a good idea, design an experiment to test it, get someone smart to look over the maths with you, write it up, submit the paper to a good quality journal, and then drink coffee while waiting for the Nobel people to get in touch.
Do you see anything wrong with the math I posted?
If you do not see anything wrong then, please, bring the best friends you have that understand this topic.
I did go through it with a very very smart guy. He is confused now.
I submitted my paper to two journals and I got rejected. That's fine, it's life
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Old 16th September 2019, 05:57 AM   #300
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Originally Posted by SDG View Post
The only attempt to point out that I am wrong came from Myriad and I showed what's wrong with it.
Where is your contribution?
SDG
There is none. Your lack of understanding of Relativity is not my problem.

Hans
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Old 16th September 2019, 06:29 AM   #301
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I'll try once more, even though you have responded extremely rudely to my previous efforts to answer your questions.

You multiply by gamma when you are converting length or duration as measured in some frame to the proper length or duration.

You divide by gamma when you are converting a proper length or duration into the length or duration you would measure in some frame.


Consider a typical somewhat sloppily worded SR example that says something like "The rocket is really 10m long, but as it zooms by the earth at 60% of the speed of light, it will appear to be only 8m long."

In other words, the rocket's proper length is 10m, its v relative to a presumed stationary earth is 0.6c, and we want to know how long it will be measured to be (not merely "appear") for an observer on earth. That's the second of the two cases above: converting a proper measurement to a measurement in some frame.

How is the 8m figure determined? It's 10m * 1/gamma.

When dealing with time measurements, remember that the measurement is duration, or elapsed time between events. If you think in vague terms like "how fast the clock runs" you can confuse yourself with reciprocals again.
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Old 16th September 2019, 06:30 AM   #302
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Originally Posted by MRC_Hans View Post
There is none. Your lack of understanding of Relativity is not my problem.

Hans
Let us talk about your understanding then.
What time interval along the train conductor's world line elapsed when 6.25s passed along the platform observer's world line?
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Old 16th September 2019, 06:40 AM   #303
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Originally Posted by Myriad View Post
...

You multiply by gamma when you are converting length or duration as measured in some frame to the proper length or duration.

You divide by gamma when you are converting a proper length or duration into the length or duration you would measure in some frame.
...
I have the same question: What time interval along the train conductor's world line elapsed when 6.25s passed along the platform observer's world line?
If you say 6.1237243569s then you are going against the left side diagram in the first place.
SDG

Edit: You are essentially saying that the train(moving) clock is ticking faster than the platform clock, opposite of what relativity claims.

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Old 16th September 2019, 07:48 AM   #304
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Originally Posted by SDG View Post
I have the same question: What time interval along the train conductor's world line elapsed when 6.25s passed along the platform observer's world line?
If you say 6.1237243569s then you are going against the left side diagram in the first place.
SDG

Edit: You are essentially saying that the train(moving) clock is ticking faster than the platform clock, opposite of what relativity claims.

The platform observer never observes or calculates any 6.25s interval for any events described in your thought experiment.

Here, again, is what you did wrong:

Quote:
One-way light proper time on the train: t'=6.1237243569s
Proper platform time for t' (time dilation): t=gamma * t'=6.25s

You were trying to convert a proper time interval on the train t' to what the platform observer would measure. That should be t' * 1/gamma.
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Old 16th September 2019, 08:58 AM   #305
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Originally Posted by SDG View Post
What did I do wrong in the calculation that I need course?
SDG
Myriad has told you. Again.

The posters here will not keep correcting your mistakes forever, even Myriad's patience will run out eventually. That will not mean that you can declare victory, it will just mean that everyone has got fed up of correcting you. Do the course, get a better understanding of SR, and then if you have sensible questions come back and ask them. At the moment your questions are not sensible.
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Old 16th September 2019, 11:11 AM   #306
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Originally Posted by SDG View Post
Let us talk about your understanding then.
What time interval along the train conductor's world line elapsed when 6.25s passed along the platform observer's world line?
SDG
No. Your lack of understanding is not my problem. And my understanding is not your problem. Go ahead and enjoy those who have the patience to play with you. This time, I'm not among them.

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Old 16th September 2019, 11:44 AM   #307
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C'mon, who here knew that Myriad's semaphore flags spelled out, "THE CLARITY IS DEVASTATING?" Surely that's worth something to this thread?
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Old 16th September 2019, 11:50 AM   #308
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Originally Posted by Myriad View Post
...
You were trying to convert a proper time interval on the train t' to what the platform observer would measure. That should be t' * 1/gamma.
If I would do that then the platform observer measures 6s according to you.
It means that the time interval on the train is 6.1237243569s for every 6s interval on the platform.
The time on the moving train is going faster not slower compared to the platform.
Is this what you are saying?
SDG

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Old 16th September 2019, 11:51 AM   #309
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Originally Posted by SDG View Post
...I did go through it with a very very smart guy. He is confused now.
I submitted my paper to two journals and I got rejected. That's fine, it's life
SDG
Is this the same guy who thinks Gravity is just another Electromagnetic Force as per your thread on the cycloid?
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Old 16th September 2019, 11:52 AM   #310
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Originally Posted by Pixel42 View Post
Myriad has told you. Again.

The posters here will not keep correcting your mistakes forever, even Myriad's patience will run out eventually. That will not mean that you can declare victory, it will just mean that everyone has got fed up of correcting you. Do the course, get a better understanding of SR, and then if you have sensible questions come back and ask them. At the moment your questions are not sensible.
So you agree with Myriad that the time on the moving train is going faster not slower compared to the platform?
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Old 16th September 2019, 11:54 AM   #311
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Originally Posted by Elagabalus View Post
C'mon, who here knew that Myriad's semaphore flags spelled out, "THE CLARITY IS DEVASTATING?" Surely that's worth something to this thread?
So you maintain the same position as Myriad?
The time on the moving train is going faster not slower compared to the platform.
Correct?
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Old 16th September 2019, 12:36 PM   #312
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Originally Posted by Elagabalus View Post
C'mon, who here knew that Myriad's semaphore flags spelled out, "THE CLARITY IS DEVASTATING?" Surely that's worth something to this thread?
I actually did learn semaphore when I was in the Boy Scouts many decades ago, but I don't think I remember it well enough to decode Myriad's avatar.
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Old 16th September 2019, 12:42 PM   #313
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Originally Posted by SDG View Post
So you agree with Myriad that the time on the moving train is going faster not slower compared to the platform?
SDG
Depends whether you're on the train or on the platform.

For the observer on the train, time passes more slowly on the platform than on the train. For the observer on the platform, time passes more slowly on the train than on the platform.
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Old 16th September 2019, 12:53 PM   #314
Elagabalus
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Originally Posted by SDG View Post
So you maintain the same position as Myriad?
The time on the moving train is going faster not slower compared to the platform.
Correct?
SDG
If I go from point A to point B in 6 seconds and at another time I go from point A to point B in 12 seconds, am I going faster or slower when compared to(relative to) my first run?
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Old 16th September 2019, 01:14 PM   #315
Myriad
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I've been partly wrong in my last several posts. I have to recant and back up.

What I said about transforming lengths between frames was correct, but I failed to take into account that time intervals are affected in the inverse way. Lengths contract from the proper length when measured from a moving frame, but time dilates (rates contract, but intervals increase).

SDG, your green rod thought experiment doesn't overthrow SR, but the problem with it is more subtle than what I said before. I apologize for the error. I'll take another look at what's really going on there.
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Old 16th September 2019, 04:58 PM   #316
Reality Check
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Originally Posted by SDG View Post
Based on SR there is no hierarchy.
But if your money is on Myriad then, ...
The fact is that even if Myriad made an error, any rational money is still on SR being correct. 114 years of textbook physics and experiments says that SR is correct. Millions of students actually learning SR know the evidence that SR is correct. This of course does not include you since you are ignoring the educational material you have been given and even Wikipedia .
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Old 16th September 2019, 05:12 PM   #317
Reality Check
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Exclamation A persistent error that other posters knowledge is relevant

Originally Posted by SDG View Post
The time on the moving train is going faster not slower compared to the platform.
Correct?
17 September 2019 SDG: A persistent error that other posters knowledge is relevant.
You are the one with the claim that SR is somehow wrong. Thus it it is your knowledge of SR that is relevant. If you are arguing from ignorance as questions of others suggests then you are automatically wrong.

The other aspect is that asking every poster in a thread the same question is a waste of their time when textbooks, Wikipedia and Google exist. Worse is the tactic seen by internet cranks in denial of actual physics of then pouncing on any ambiguities, misunderstanding or errors in the answers. Of course multiple posters will not give textbook correct answers! Do not act like one of those, SDG. Be honest and actually learn SR.

Last edited by Reality Check; 16th September 2019 at 05:13 PM.
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Old 16th September 2019, 08:20 PM   #318
Myriad
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Originally Posted by SDG View Post
We will extend our thought experiment by introducing a 6.25cs rod on the platform as per the next figure. The platform rod (light green) is aligned with x=0. The platform observer sends a light beam along the platform rod at C event when t=t’=0 and x=x’=0. The train conductor observers the light in the platform frame when it hits the end of the rod.

https://i.imgur.com/gTyN8U7.png

A quick recapitulation of our original calculations.

Platform half the train car length contracted: L=6cs
Proper length: L'=gamma * 6cs=6.1237243569cs
One-way light proper time on the train: t'=6.1237243569s
Proper platform time for t' (time dilation): t=gamma * t'=6.25s

The quick calculation for the light propagation of the platform rod from the train reference frame applying the steps from the above quick recapitulation.
Because the calculation is done from the train frame point of view then the train axes are x, ct, platform axes are x’, ct’.

The contracted rod as seen from the train frame: Lrod=6.1237243569cs
Proper length in the platform frame: L'rod=gamma * 6.1237243569cs = 6.25cs
One-way light proper time in the platform frame: t'=6.25s
Proper train time for t' (time dilation): [i]t=gamma * t'=6.3788795384s[/i

Okay, starting over with this thought experiment...

The platform observer measures the following:

green rod is 6.25 cs long and stationary
light flash from the origin reaches the end of the rod at t' = 6.25 cs

The conductor measures the following:

green rod is 6.124 cs long and is moving in the -x direction at c/5
light flash from the origin reaches the end of the rod at t = 5.10 cs

Each think the other's clock is running slowly by a factor of gamma. But neither is using the other's clock to time anything. If they did use the other's clock to time something, they could multiply the interval measured by the other's clock by gamma to get proper time for their own frame.
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Old 16th September 2019, 08:40 PM   #319
Reality Check
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Exclamation An ignorant question because SR time dilation is really reciprocal

Originally Posted by SDG View Post
Question 2: Is SR reciprocity of time dilation real?...
17 September 2019 SDG: An ignorant question because SR time dilation is really reciprocal.
SR time dilation contains the relative speed of the observers. An observer Alice will measure a speed v for observer Bob. Bob will measure the same speed v for Alice. They must calculate the same gamma factor and the same time dilation.
Also what do you mean by "real"? We have measured that time dilation is real and matches SR. A more coherent question would be : Has SR reciprocity of time dilation been measured?

Followed by an irrelevant thought experiment when Einstein worked this out in 1905.

5 September 2019 SDG: An ignorant "Where is time dilation in all of this" question.

Last edited by Reality Check; 16th September 2019 at 08:46 PM.
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Old 17th September 2019, 06:05 AM   #320
SDG
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Originally Posted by Pixel42 View Post
Depends whether you're on the train or on the platform.

For the observer on the train, time passes more slowly on the platform than on the train. For the observer on the platform, time passes more slowly on the train than on the platform.
This is in contradiction with the relativity of simultaneity, see the right diagram of the post #296.
If you do not see it this way, please, give me a couple posts, I'll explain it.
SDG
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