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

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Old 17th September 2019, 06:06 AM   #321
SDG
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Originally Posted by Elagabalus View Post
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?
Not enough information to say if you are going faster or slower.
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Old 17th September 2019, 06:37 AM   #322
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Originally Posted by Myriad View Post
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.
I am glad we established that for 6.1237243569s of the train proper time interval we have 6.25s of the platform proper time interval!!!!


The end of the green rod is reached at 5.10310363075s of the train proper time.
How much time elapsed on the platform at the same time?
Using LT we get:
t'=gamma*(t+xv/(c^2))=1.0206207261*(5.10310363075s+5.10310363075c s*c/(5c^2))= 1.0206207261*(5.10310363075s+1.02062072615s)=1.020 6207261*6.1237243569s=6.25s

This is the proper time interval on the platform as seen from the train.
There is time dilation going from platform back to train t=gamma * t'=6.3788795384s.

Here is the contradiction!
The platform proper time interval 6.25s cannot match two different proper time intervals on the train at the same time: 6.1237243569s and 6.3788795384s
It is captured on the right diagram of the post #296
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Old 17th September 2019, 07:55 AM   #323
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Originally Posted by SDG View Post
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
I see it the way Einstein saw it. What I posted was the cornerstone of his Special Theory of Relativity. If you don't see it that way, I can only suggest once again that you do that online course. I have no interest in trying to identify and correct your misunderstandings and errors, I don't have Myriad's patience.
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Old 17th September 2019, 09:26 AM   #324
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Originally Posted by Pixel42 View Post
I see it the way Einstein saw it. What I posted was the cornerstone of his Special Theory of Relativity. If you don't see it that way, I can only suggest once again that you do that online course. I have no interest in trying to identify and correct your misunderstandings and errors, I don't have Myriad's patience.
That's OK, do what you have to do.
My previous post showed what is wrong with the SR.
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Old 17th September 2019, 11:26 AM   #325
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Ladies and Gentlemen of the ISF/SMMT, the Einsteinian Reign of Terror is over. SDG will now be the official point man on the ISF Hyper-driveô project.* Please welcome our new overlord with open arms and grovel appropriately when in his presence. That is all. Now go to your cubicles.





*Taking over from Anders Lindman's desultory efforts.
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Old 17th September 2019, 11:31 AM   #326
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Originally Posted by SDG View Post
I am glad we established that for 6.1237243569s of the train proper time interval we have 6.25s of the platform proper time interval!!!!


The end of the green rod is reached at 5.10310363075s of the train proper time.
How much time elapsed on the platform at the same time?
Using LT we get:
t'=gamma*(t+xv/(c^2))=1.0206207261*(5.10310363075s+5.10310363075c s*c/(5c^2))= 1.0206207261*(5.10310363075s+1.02062072615s)=1.020 6207261*6.1237243569s=6.25s

This is the proper time interval on the platform as seen from the train.

This is the proper time interval on the platform as seen by the platform observer, and as calculated by the conductor using the Lortentz transform on his own observations in the train frame.

Quote:
There is time dilation going from platform back to train
t=gamma * t'=6.3788795384s.

That's not the Lorentz transformation back into the train frame. Have you forgotten that the platform is moving in the train frame?

Quote:
Here is the contradiction!

Here is the error you made. You've taken the conductor's measurements and applied the same time dilation factor to them twice. That produces a meaningless result.

There is no contradiction. The platform observer measures 6.25s. The conductor measures 5.10 s. Either one can calculate what the other will measure by applying the Lorentz transformation correctly.
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Old 17th September 2019, 11:33 AM   #327
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One more asteroid or meteor is approaching the Solar system
C/2019 Q4
This time we will see a mysterious deceleration, right after passing ecliptic.
Not a acceleration effect as seen by Oumuamua
Why ?
Because of the large speed it is moving at can only be maintained by a relative strong force. In this case the force of the Sun....
Again, - No it is not a strange object from another solar system. – So long we don’t understand MTR we also don’t understand how strange orbits we really must expect.
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Old 17th September 2019, 11:46 AM   #328
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Originally Posted by Bjarne View Post
One more asteroid or meteor is approaching the Solar system
C/2019 Q4
This time we will see a mysterious deceleration, right after passing ecliptic.
Not a acceleration effect as seen by Oumuamua
Why ?
Because of the large speed it is moving at can only be maintained by a relative strong force. In this case the force of the Sun....
Again, - No it is not a strange object from another solar system. Ė So long we donít understand MTR we also donít understand how strange orbits we really must expect.
Wrong thread, Bjarne.

http://www.internationalskeptics.com...d.php?t=338830
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Old 17th September 2019, 12:30 PM   #329
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Originally Posted by Myriad View Post
This is the proper time interval on the platform as seen by the platform observer, and as calculated by the conductor using the Lortentz transform on his own observations in the train frame.




That's not the Lorentz transformation back into the train frame. Have you forgotten that the platform is moving in the train frame?




Here is the error you made. You've taken the conductor's measurements and applied the same time dilation factor to them twice. That produces a meaningless result.

There is no contradiction. The platform observer measures 6.25s. The conductor measures 5.10 s. Either one can calculate what the other will measure by applying the Lorentz transformation correctly.
It appears to me that you have forgotten...
We started with Lorentz length contracted 6cs half the train car length, the light hit the ends at 5s and 7.5s.
Nevertheless you admitted that the proper time on the train for the A', B' events is 6.1237243569s and the time dilation for that proper time interval is 6.25s back on the platform because train moves and the time on the platform ticks faster.

Now we have time 6.25s on the platform, the platform moves in the train frame therefore there has to be time dilation back to train reference frame 6.3788795384s because the train clock ticks faster. This is reciprocity.

Please, have a look here again:



Compare the left and the right diagrams, the relationship between the time dilation.
How we went from 6.1237243569s to 6.25s on the left side diagram.
The same way we will go from 6.25s to 6.3788795384s on the right side diagram - the green line.
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Old 17th September 2019, 01:15 PM   #330
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Originally Posted by SDG View Post
It appears to me that you have forgotten...
We started with Lorentz length contracted 6cs half the train car length, the light hit the ends at 5s and 7.5s.
Nevertheless you admitted that the proper time on the train for the A', B' events is 6.1237243569s and the time dilation for that proper time interval is 6.25s back on the platform because train moves and the time on the platform ticks faster.

Now we have time 6.25s on the platform, the platform moves in the train frame therefore there has to be time dilation back to train reference frame 6.3788795384s because the train clock ticks faster. This is reciprocity.
No, the time is slower for the platform guy. Think about it. Each second or each tick lasts for a longer duration for the platform guy than for the train guy.
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Old 17th September 2019, 01:31 PM   #331
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Originally Posted by SDG View Post
Now we have time 6.25s on the platform, the platform moves in the train frame therefore there has to be time dilation back to train reference frame 6.3788795384s because the train clock ticks faster. This is reciprocity.

Perform the Lorentz time transform of the platform's proper time interval of 6.25s and v = -c/5 into the train frame correctly (don't forget that minus sign, the platform is moving in the -x direction in the train frame!) and you'll get t=5.1031036305.

Yes, if you multiply 6.25 by 1.0206207261 you get 6.3788795384. That figure has no particular significance in either frame. (Okay, it actually does represent something. It's the proper time, in the train frame, for the light pulse to reach the point on the train that started out adjacent to the end of the green rod at t=t'=0. Although that point is actually beyond the front of the train. But maybe there's a pole sticking out the engine or something.)
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Old 17th September 2019, 01:31 PM   #332
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Originally Posted by Elagabalus View Post
No, the time is slower for the platform guy. Think about it. Each second or each tick lasts for a longer duration for the platform guy than for the train guy.
If we round the numbers to 1/100 and each hundredth is a tick.
6.25 comparing to 6.12 - for 612 ticks on the train there are 625 ticks on the platform.
I stand by what I said. There are more clock ticks on the platform when compared to train clock ticks.
Time on the platform ticks faster.
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Old 17th September 2019, 01:39 PM   #333
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Originally Posted by Myriad View Post
Perform the Lorentz time transform of the platform's proper time interval of 6.25s and v = -c/5 into the train frame correctly (don't forget that minus sign, the platform is moving in the -x direction in the train frame!) and you'll get t=5.1031036305.

Yes, if you multiply 6.25 by 1.0206207261 you get 6.3788795384. That figure has no particular significance in either frame. (Okay, it actually does represent something. It's the proper time, in the train frame, for the light pulse to reach the point on the train that started out adjacent to the end of the green rod at t=t'=0. Although that point is actually beyond the front of the train. But maybe there's a pole sticking out the engine or something.)
I hope you are starting to see why I say there is a problem.
The time 6.25s on the platform cannot represent two times on the train.
SDG
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Old 17th September 2019, 02:41 PM   #334
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Exclamation Time on the platform does not represents 2 times on the train

Originally Posted by SDG View Post
I hope you are starting to see why I say there is a problem.
The time 6.25s on the platform cannot represent two times on the train.
SDG
18 September 2019 SDG: Your ignorance is the problem. Time on the platform does not represents 2 times on the train.

Myriad wrote as you quoted that the Lorentz transformation transforms a time interval on the platform to a single time interval on the train. A second time is "the proper time, in the train frame". The train frame is what is measured on the train. The physics is that there can be 2 inertial frames of reference, observers make measurements in their own frames (proper time intervals and distances) and the Lorentz transformation says what an observer will measure for events in another frame. This is basic SR that you need to learn, SDG.

Last edited by Reality Check; 17th September 2019 at 02:46 PM.
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Old 17th September 2019, 02:46 PM   #335
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Originally Posted by Bjarne View Post
One more asteroid or meteor is approaching the Solar system
C/2019 Q4
This time we will see a mysterious deceleration, right after passing ecliptic.
Not a acceleration effect as seen by Oumuamua

Why ?
Because of the large speed it is moving at can only be maintained by a relative strong force. In this case the force of the Sun....
Again, - No it is not a strange object from another solar system. Ė So long we donít understand MTR we also donít understand how strange orbits we really must expect.
Well, you made a prediction. Let's see how this one turns out.

Hans
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Old 17th September 2019, 02:47 PM   #336
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Originally Posted by SDG View Post
I hope you are starting to see why I say there is a problem.
The time 6.25s on the platform cannot represent two times on the train.
SDG

Why can't one interval of time apply to two different events (light reaching the end of the rod, light reaching the point in front of the train) in a different frame at different locations? That's kind of how time and space work.
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Old 17th September 2019, 03:02 PM   #337
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Originally Posted by SDG View Post
If we round the numbers to 1/100 and each hundredth is a tick.
6.25 comparing to 6.12 - for 612 ticks on the train there are 625 ticks on the platform.
I stand by what I said. There are more clock ticks on the platform when compared to train clock ticks.
Time on the platform ticks faster.
SDG
There are 100 ticks in both frames 6.25/100 and 6.12/100. The duration for the conductor guy is .0612 and the duration for the platform guy is .0625. Each individual tick is longer (takes more time to get to each tick) so the train guy sees the platform guy's time as slow.
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Old 17th September 2019, 05:08 PM   #338
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Originally Posted by Myriad View Post
Why can't one interval of time apply to two different events (light reaching the end of the rod, light reaching the point in front of the train) in a different frame at different locations? That's kind of how time and space work.
If there is not 1-1 and only one 1-1 mapping between time intervals of two different inertial frames then we do not have velocity and acceleration between the inertial frames.
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Old 17th September 2019, 05:21 PM   #339
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Originally Posted by Elagabalus View Post
There are 100 ticks in both frames 6.25/100 and 6.12/100. The duration for the conductor guy is .0612 and the duration for the platform guy is .0625. Each individual tick is longer (takes more time to get to each tick) so the train guy sees the platform guy's time as slow.
No, 6.25s has 6.25 * 9192631770 ticks/periods/cycles in the platform frame and 6.12s has 6.12 * 9192631770 ticks/periods/cycles in the train frame of caesium ground state transitions as per SI second definition.
There are more cycles on the platform than on the train in the first iteration of the thought experiment.
SDG

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Old 17th September 2019, 05:46 PM   #340
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Originally Posted by SDG View Post
No, 6.25s has 6.25 * 9192631770 ticks/periods/cycles in the platform frame and 6.12s has 6.12 * 9192631770 ticks/periods/cycles in the train frame of caesium ground state transitions as per SI second definition.
There are more cycles on the platform than on the train in the first iteration of the thought experiment.
SDG
The caesium would run slow to the train guy too.
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Old 17th September 2019, 06:01 PM   #341
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Originally Posted by Elagabalus View Post
The caesium would run slow to the train guy too.
When a caesium clock is mounted on the train and it is not moving within the train then the train is clock's rest frame and that's the definition of the second on the train.
The same goes for the platform, when a caesium clock is mounted on the platform and it is not moving on the platform then the platform is clock's rest frame and that's the definition of the second on the platform.
SDG

Edit: My previous response was "sloppy", it should have included the clock's rest frame definition.

Last edited by SDG; 17th September 2019 at 06:08 PM.
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Old 17th September 2019, 06:15 PM   #342
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Originally Posted by SDG View Post
If there is not 1-1 and only one 1-1 mapping between time intervals of two different inertial frames then we do not have velocity and acceleration between the inertial frames.
SDG

You seem to have an issue with the fact that if you calculate the Lorentz transform correctly, taking the delta v into account, you get one answer; and if you calculate it incorrectly, computing the timing for a different event instead, you get a different answer.

I think that's to be expected and is in no way a flaw or contradiction in SR.
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Old 17th September 2019, 07:06 PM   #343
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Originally Posted by Bjarne View Post
One more asteroid or meteor is approaching the Solar system ...
A ignorant and delusional post.
We have not detected an asteroid. We have certainly not detected a meteor whizzing thru our atmosphere !
C/2019 Q4 (Borisov) is inside the Solar System (first detected at ~3 AU from the Sun).
C/2019 Q4 (Borisov) is a comet that has come from outside of the Solar System. It is delusional to state that it did not come from another solar system.

The major delusion is making up a fairy story. He has no prediction for the future path of C/2019 Q4 (Borisov) and is even ignorant about what and where it is !
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Old 17th September 2019, 07:30 PM   #344
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Originally Posted by Myriad View Post
You seem to have an issue with the fact that if you calculate the Lorentz transform correctly, taking the delta v into account, you get one answer; and if you calculate it incorrectly, computing the timing for a different event instead, you get a different answer.

I think that's to be expected and is in no way a flaw or contradiction in SR.
No calculation was done incorrectly.
The calculations from contracted 6cs to 6.25s are correct.
The calculations from contracted 6.1237243569cs to 6.3788795384s are correct as well.
The proper platform time interval of 6.25s is in the middle and it has two proper train time intervals.
That's not good.

What incorrect calculation you have in mind?
SDG
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Old 17th September 2019, 07:50 PM   #345
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Originally Posted by SDG View Post
When a caesium clock is mounted on the train and it is not moving within the train then the train is clock's rest frame and that's the definition of the second on the train.
The same goes for the platform, when a caesium clock is mounted on the platform and it is not moving on the platform then the platform is clock's rest frame and that's the definition of the second on the platform.
SDG

Edit: My previous response was "sloppy", it should have included the clock's rest frame definition.
Did you watch the video I gave you about the twin paradox?
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Old 17th September 2019, 08:41 PM   #346
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Thumbs down Abysmal ignorance about SR- Lorentz transformation and inertial frames

Originally Posted by SDG View Post
If there is not 1-1 and only one 1-1 mapping between time intervals of two different inertial frames then we do not have velocity and acceleration between the inertial frames.
SDG
18 September 2019 SDG: Abysmal ignorance about SR - Lorentz transformation and inertial frames.
The Lorentz transformation in SR is a "1-1 and only one 1-1 mapping between time intervals of two different inertial frames" !
The ignorance in "velocity and acceleration between the inertial frames" is
  • Inertial frames are not accelerated.
  • The velocity between two different inertial frames is what the observers measure.
This is fundamental SR thus the abysmal ignorance.
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Old 18th September 2019, 12:39 AM   #347
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Originally Posted by Reality Check View Post
This is fundamental SR thus the abysmal ignorance.
It's not as if SR is that difficult to understand, unlike GR and quantum theory the maths is mostly simple algebra. The biggest problem with it is that it's counterintuitive, but once you understand the implications of the fact that the speed of light is always measured to be the same by observers in all inertial reference frames, regardless of their relative velocities, the rest should be plain sailing. It certainly still seems odd that observers in different inertial frames will always measure each others length and time intervals to be less than they measure them themselves, but the maths is straightforward. More importantly it always give the right answer, verified in any number of experiments.
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Old 18th September 2019, 02:41 AM   #348
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Originally Posted by Elagabalus View Post
Did you watch the video I gave you about the twin paradox?
Yes,
SDG
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Old 18th September 2019, 07:31 AM   #349
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Originally Posted by SDG View Post
No calculation was done incorrectly.
The calculations from contracted 6cs to 6.25s are correct.
The calculations from contracted 6.1237243569cs to 6.3788795384s are correct as well.
The proper platform time interval of 6.25s is in the middle and it has two proper train time intervals.
That's not good.

What incorrect calculation you have in mind?
SDG

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.

In the train frame, no event defined in the thought experiment takes place at 6.25s or 7.5s.

No event defined in the thought experiment takes place in either frame at 6.379s.

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.
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Old 18th September 2019, 08:08 AM   #350
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SDG, we can simplify the argument you're making. We don't need trains or to fuss around with contracted lengths. Just consider two inertial frames with a relative velocity (and some corresponding gamma) with a proper time clock in each frame.

1. In frame A, the clock measures some time interval t.
2. In frame B, due to time dilation, A's time interval t will correspond to a time interval t*gamma.
3. Back in frame A, B's time interval t*gamma will correspond to t*gamma*gamma.
4. Back in frame B, A's time interval t*gamma*gamma will correspond to t*gamma^3.
5. Back in frame A, B's time interval t*gamma^3 will correspond to t*gamma^4.
6... And so on.

How can the same time interval have all those different values? (t * gamma ^ (any even number) in frame A, and t * gamma ^ (any odd number) in frame B.)

The problem is, in step 2, the result of B's calculation of t*gamma doesn't represent any actual event in frame B. There's nothing happening in frame B when B's clock reads t*gamma, that makes it make any sense for A to apply time dilation to t*gamma in step 3. A and B can sit there multiplying numbers all day if they want to, but the results don't mean anything.

But suppose B did generate an event when B's clock reaches t*gamma, say by flashing a light. Then A could flash a light at t*gamma^2, and so forth. And the result of that would be... a lot of different events occurring at different times (and which could be correctly translated into either frame by using the correct LT calculation taking the velocity into account). Which is no contradiction of anything.
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Old 18th September 2019, 09:06 AM   #351
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Originally Posted by MRC_Hans View Post
Well, you made a prediction. Let's see how this one turns out.

Hans
Not much, based on for example 40 km/s,- the deceleration is 0.000000008 m/s - This will only decelerate the meteor a few hundred kilometer within 3 month, - and maybe not sure we can measure.
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Old 18th September 2019, 11:00 AM   #352
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Originally Posted by Bjarne View Post
Not much, based on for example 40 km/s,- the deceleration is 0.000000008 m/s - This will only decelerate the meteor a few hundred kilometer within 3 month, - and maybe not sure we can measure.
So you predict it will not accelerate as it approaches the Sun and decelerate when it moves away from the Sun?

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Old 18th September 2019, 11:29 AM   #353
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More things that Bjarne doesn't understand. And if we can't measure it, why even bring it up.

60 seconds * 60 minutes * 24 hours * 30 days * 3 months * 0.000000008 m/s = 0.62208m (or just a little over 2 feet)
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Old 18th September 2019, 12:27 PM   #354
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Originally Posted by Bjarne View Post
Not much, based on for example 40 km/s,- the deceleration is 0.000000008 m/s - This will only decelerate the meteor a few hundred kilometer within 3 month, - and maybe not sure we can measure.
I think you're just feeling salty someone else took over the contrarian position in this thread.
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Old 18th September 2019, 03:20 PM   #355
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Thumbs down Adds to his previous ignorant and delusional post

Originally Posted by Bjarne View Post
Not much,....
A number pulled out of nowhere is actually nothing at all !
19 September 2019 Bjarne: Adds to his previous ignorant and delusional post with a number pulled out of thin air.
Originally Posted by Reality Check View Post
A ignorant and delusional post.
We have not detected an asteroid. We have certainly not detected a meteor whizzing thru our atmosphere !
C/2019 Q4 (Borisov) is inside the Solar System (first detected at ~3 AU from the Sun).
C/2019 Q4 (Borisov) is a comet that has come from outside of the Solar System. It is delusional to state that it did not come from another solar system.

The major delusion is making up a fairy story. He has no prediction for the future path of C/2019 Q4 (Borisov) and is even ignorant about what and where it is !
For example, the current velocity of C/2019 Q4 (Borisov) will increase as it gets to closer to the Sun and then decrease as it travels out of the Solar System. Where is the calculation of that?

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Old 18th September 2019, 06:29 PM   #356
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Thanks for a very clear exposition Myriad.
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Old 18th September 2019, 06:48 PM   #357
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Originally Posted by Bjarne View Post
...the meteor
Still thinks that the comet C/2019 Q4 (Borisov) is a meteor (and so inside the Earths atmosphere !).

The problem is not measuring his imaginary number.
Comet C/2019 Q4 (Borisov) will be decelerating and accelerating because it is in a hyperbolic orbit around the Sun.
Comet C/2019 Q4 (Borisov) will be decelerating and accelerating because it is a comet with cometary activity such as jets. Astronomers will probably use these changes in the trajectory to double-check the mass of comet C/2019 Q4 (Borisov)
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Old 18th September 2019, 07:27 PM   #358
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Originally Posted by Myriad View Post
SDG, we can simplify the argument you're making. We don't need trains or to fuss around with contracted lengths. Just consider two inertial frames with a relative velocity (and some corresponding gamma) with a proper time clock in each frame.

1. In frame A, the clock measures some time interval t.
2. In frame B, due to time dilation, A's time interval t will correspond to a time interval t*gamma.
3. Back in frame A, B's time interval t*gamma will correspond to t*gamma*gamma.
4. Back in frame B, A's time interval t*gamma*gamma will correspond to t*gamma^3.
5. Back in frame A, B's time interval t*gamma^3 will correspond to t*gamma^4.
6... And so on.

How can the same time interval have all those different values? (t * gamma ^ (any even number) in frame A, and t * gamma ^ (any odd number) in frame B.)

The problem is, in step 2, the result of B's calculation of t*gamma doesn't represent any actual event in frame B. There's nothing happening in frame B when B's clock reads t*gamma, that makes it make any sense for A to apply time dilation to t*gamma in step 3. A and B can sit there multiplying numbers all day if they want to, but the results don't mean anything.

But suppose B did generate an event when B's clock reaches t*gamma, say by flashing a light. Then A could flash a light at t*gamma^2, and so forth. And the result of that would be... a lot of different events occurring at different times (and which could be correctly translated into either frame by using the correct LT calculation taking the velocity into account). Which is no contradiction of anything.
Imagine 1mm cavity at x=0 and x'=0 on platform and train frames where light bounces back and forth.
One cycle - the light goes from x=0 to x=-1mm and then it comes back to x=0 => the light clock.
The same in the other frame.
The light clock is used to measure v=ds/dt, a=dv/dt.

It is not true what you say here:
Quote:
The problem is, in step 2, the result of B's calculation of t*gamma doesn't represent any actual event in frame B. There's nothing happening in frame B when B's clock reads t*gamma, that makes it make any sense for A to apply time dilation to t*gamma in step 3.
The proper time intervals of length t and t' along the respective world lines are related through gamma of the LT.
It has to be one to one relationship!
If there is not one and only one 1-1 relationship then inertial observers cannot say anything about the physics in the other inertial frame.
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Old 18th September 2019, 07:32 PM   #359
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Originally Posted by Robin View Post
Thanks for a very clear exposition Myriad.
What is the clear exposition? His understanding of what is happening is lacking.
I have to call it as it is. He made no correction to what I said so far.
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Old 18th September 2019, 07:47 PM   #360
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Originally Posted by SDG View Post
What is the clear exposition? His understanding of what is happening is lacking.

I have to call it as it is. He made no correction to what I said so far.

SDG
I might be missing something, I admit, this is not my subject.

Can you clarify what events A, B and C represent on you diagrams?

The diagrams seem to relate to you previous example and not to the one about the rod on the platform.
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