# Basic Special Relativity Question

Discussion in 'Physics & Math' started by Fednis48, Apr 22, 2013.

1. ### PeteIt's not rocket surgeryRegistered Senior Member

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I'd like to know what you think.
You said it's real, but not measurable. To me, that seems inconsistent, so I'm trying to understand what you're thinking.

Measuring it is fairly trivial in principle, but the practicalities are something else. If we could have a timer precise to the millisecond moving on a rail at 100km/s, synchronized (by einstein synchronization) with a similar timer on a similar track 1000km away, then it could be done.

Not Nobel prize worthy, I'm afraid.

3. ### TachBannedBanned

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How? Let's see the details. You waste so much time with repeating the same question, you could have used all this time figuring out the details of the experiment. This should be an incentive, since no one else, to date , has come up with an experimental setup. You do not seem worried that there is no "RoS test" section here, so go for it!

5. ### TachBannedBanned

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What you need to get is the times $t^"_k$ and the corresponding positions $x^"_k(t^"_k),y^"_k(t^"_k)$ when the rod is coming into contact with the car floor. How do you do that? Your above setup doesn't cover any of this.

7. ### PeteIt's not rocket surgeryRegistered Senior Member

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The above setup is a basic test of RoS.
And I'm really interested in understanding your position:
Do you think RoS is physically meaningful? Surely not, since you think it can't be measured. But then why do you think it is real?

8. ### TachBannedBanned

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So, how do you measure the positions $x^"_k(t^"_k),y^"_k(t^"_k)$? Your setup shows nothing of that. It only shows that you never ran an experiment.

9. ### PeteIt's not rocket surgeryRegistered Senior Member

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You seem confused. This simple RoS test setup is not related to the thread scenario. It's a separate, simpler test, involving four clocks and no rods.

10. ### TachBannedBanned

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I have been very precise : show the setup for the falling rod. Please do so.

11. ### PeteIt's not rocket surgeryRegistered Senior Member

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You asked for a test of RoS, I gave you one. Do you agree that it would in principle measure RoS?

12. ### TachBannedBanned

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I was very precise on what I asked you. I asked you for a test of the "rod bending".
You came up with a "RoS test". But it has serious flaws, you obviously rushed without thinking it through, so, please address the shortcomings of your "RoS test"

13. ### UndefinedBannedBanned

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If the platform observer has a rod-dropping setup too, and both the train observer and platform observer drop their respective rods as the train passes, OR as the platform passes "relatively speaking", then if Tach's claim that the "clocks" labels are meaningless for one frame (platform S") then they would also be meaningless for the other frame (train S', insofar as train observers clock timing of platform is concerned). I don't mention rod frame S because that is proper frame and the observer clocks are what is being questioned by Tach. Can someone clarify naively for me why SR even exists as a theory if, as in this two-way rod-dropping relativity exercise I just described, both the platform and the train clock "labeling" may be considered "meaningless" after all, as Tach claims?

14. ### brucepValued Senior Member

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No measurements whether they are conducted in the local proper frame or from a remote coordinate frame are meaningless. Just like the theoretical predictions for the local and remote coordinates are not meaningless. Maybe you should ask Tach to explain why a empirical measurement or theoretical prediction is 'meaningless'. I really hate bullshit terminology. Meaningless bullshit.

15. ### UndefinedBannedBanned

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I agree.

I tried asking him to explain himself before. He thinks my questions are "gibberish". And I have found that Tach's "explanations" so far are the "gibberish". He says he has stopped "free lessons" for me even though his "lessons" have been useless so far. So I stopped asking Tach to explain himself because he just posts his usual links which do not support his "explanations" and claims so far. Can you ask Tach to explain himself there, he respects your questions more than mine I suspect.

Yes indeed, me too, that's why I always ask for the naive explanation based on clear terminology that isn't confusing because it is used loosely or in the wrong context and such. I like precise terms for precise things too!

16. ### eramSciengineerValued Senior Member

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It's alright, Undefined is not really fluent in English.

Last edited: May 9, 2013
17. ### PeteIt's not rocket surgeryRegistered Senior Member

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90 posts of sidetrack have been moved to a separate thread: [post=134678]Is relativity of simultaneity measurable?[/post]

18. ### PeteIt's not rocket surgeryRegistered Senior Member

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10,166
Back to the topic.