Basic Special Relativity Question

Imagine that you set a string of synchronized clocks on the falling rod, another string on the floor of the car and a third one on the platform.
The rod passes through the slit at a zero angle, both the clocks on the rod and the ones on the car floor show simultaneous contact. This is because there is no relative motion between the rod and the car floor in the x direction.
The rod contacts the platform with all points at the same time in the frame of the rod. But in the frame of the platform, all the clocks in the string show different time of contact (because there is desynchronization in the x direction, the direction of relative motion between the rod and the platform). The fact that the platform clocks show different coordinate time does NOT change the physics of the contact, the contact is the same in both frames (otherwise you get your PoR violation).

The platform considers all of its own clocks to by synchronized. In other words, for any single instant of time, all of the platform's own clocks display the same time. By your own admission above, the times displayed on the platform clocks are all different when the rod makes contact. Thus the platform frame says the contact does not occur in one single instant, but rather occurs progressively over a span of time. As practically everyone has been telling you, that means the endpoints make contact simultaneously according to the train frame and the rod frame, but non-simultaneously according to the platform frame. That is the very reason why the term "Relativity of Simultaneity" exists.

Your claim that this amounts to a violation of the Principle of Relativity is false. Einstein starts with PoR as one of his postulates, and RoS manifests itself as a result.
 
I have already addressed that. You think anyone cares about yours?

You said it was a paradox. It was an intellectually dishonest attempt to assert there is a paradox. So I agree with Tach that you're a crank. Do stuff like that and reap the consequences in public science forums. Probably noticed that already.
 
The platform considers all of its own clocks to by synchronized. In other words, for any single instant of time, all of the platform's own clocks display the same time. By your own admission above, the times displayed on the platform clocks are all different when the rod makes contact. Thus the platform frame says the contact does not occur in one single instant, but rather occurs progressively over a span of time.

You promised to shut up but you can't keep your promise. The fact that the platform clocks show different times means nothing for the physics of the problem, coordinate time is just a label , the fact that the labels are different do not change the physics , i.e. it does not make the rod hit sequentially the platform. If it did, then the platform observer would measure a permanent deformation that is absent to the car train observer, hence the violation of PoR that you fail to understand.

As practically everyone has been telling you, that means the endpoints make contact simultaneously according to the train frame and the rod frame, but non-simultaneously according to the platform frame. That is the very reason why the term "Relativity of Simultaneity" exists.

I understand very well what RoS means. You miss the point that RoS manifests itself simply by having different time labels applied to the contact points, contact itself is the same in all frames. If you think otherwise, you have devised a means of testing RoS experimentally. Such a thing does not exist for reasons just explained: coordinate time is just a series of (untestable) labels.
There are no experimental tests for RoS and there will never be one.
 
Pete's line of reasoning is valid.

No it's not. Bogus contrived experimental models are only valid for cranks. You don't get to make up bullshit measurements recorded in a remote coordinate frame that don't transform to the invariant measurements made in the local proper frame of the rod. That's what cranks do to 'show their ass in public' and how intellectually dishonest they are.
 
You promised to shut up but you can't keep your promise. The fact that the platform clocks show different times means nothing for the physics of the problem, coordinate time is just a label , the fact that the labels are different do not change the physics , i.e. it does not make the rod hit sequentially the platform. If it did, then the platform observer would measure a permanent deformation that is absent to the car train observer, hence the violation of PoR that you fail to understand.



I understand very well what RoS means. You miss the point that RoS manifests itself simply by having different time labels applied to the contact points, contact itself is the same in all frames. If you think otherwise, you have devised a means of testing RoS experimentally. Such a thing does not exist for reasons just explained: coordinate time is just a series of (untestable) labels.
There are no experimental tests for RoS and there will never be one.

All this thread is about is who does and does not understand basic physics principles associated with relativistic experimental results. It starts with the physics then the math follows. Not the opposite.
 
I understand very well what RoS means. You miss the point that RoS manifests itself simply by having different time labels applied to the contact points, contact itself is the same in all frames. If you think otherwise, you have devised a means of testing RoS experimentally. Such a thing does not exist for reasons just explained: coordinate time is just a series of (untestable) labels.
There are no experimental tests for RoS and there will never be one.
"Contact" is just another event in spacetime. Since you're talking about two space-like separated ends of a rod, their respective "contact events" are necessarily space-like separated; therefore the bloomin' ordering of those events is not the same in all frames.
 
The fact that the platform clocks show different times means nothing for the physics of the problem, coordinate time is just a label , the fact that the labels are different do not change the physics.

All you are doing is "transforming away" the problem by transforming it back into the train or rod frame. When I did that, you said we had to address the problem as if the other frame does not exist. In that case, the only clocks the platform has to reference are its own clocks, and they measure the contact events to be non-simultaneous.


I understand very well what RoS means. You miss the point that RoS manifests itself simply by having different time labels applied to the contact points, contact itself is the same in all frames.

So, when Einstein said that the lightning strikes were simultaneous in one frame, but non-simultaneous in the other frame, you think he is really saying that the lightning strikes were actually simultaneous in all frames, but that RoS was manifesting itself simply as different time labels? Nice!


If you think otherwise, you have devised a means of testing RoS experimentally. Such a thing does not exist for reasons just explained: coordinate time is just a series of (untestable) labels.
There are no experimental tests for RoS and there will never be one.

What makes you think RoS is not measurable? Here is a paper where they are proposing an experiment, contrary to your bizarre claims:

http://arxiv.org/pdf/physics/0501045v1.pdf

"Proposal for a Satellite-Borne Experiment to Test Relativity of Simultaneity in Special Relativity"
 
All you are doing is "transforming away" the problem by transforming it back into the train or rod frame.

No, I am not doing any of such. You are trying to reduce things to your limited level of understanding. In fact, this is exactly the type of nonsense you have tried at the beginning of the thread.








What makes you think RoS is not measurable? Here is a paper where they are proposing an experiment, contrary to your bizarre claims:

http://arxiv.org/pdf/physics/0501045v1.pdf

"Proposal for a Satellite-Borne Experiment to Test Relativity of Simultaneity in Special Relativity"

Three problems:

1. The paper isn't published
2. No one did the experiment
3. J.H. Field is known as a fringer.
 
All you are doing is "transforming away" the problem by transforming it back into the train or rod frame. When I did that, you said we had to address the problem as if the other frame does not exist. In that case, the only clocks the platform has to reference are its own clocks, and they measure the contact events to be non-simultaneous.




So, when Einstein said that the lightning strikes were simultaneous in one frame, but non-simultaneous in the other frame, you think he is really saying that the lightning strikes were actually simultaneous in all frames, but that RoS was manifesting itself simply as different time labels? Nice!




What makes you think RoS is not measurable? Here is a paper where they are proposing an experiment, contrary to your bizarre claims:

http://arxiv.org/pdf/physics/0501045v1.pdf

"Proposal for a Satellite-Borne Experiment to Test Relativity of Simultaneity in Special Relativity"

"Transforming away". ? There's only one frame in which the measurements are invariant. The local proper frame where the measurements are made. Remote coordinate frame measurements are frame dependent. Make sense? Really. Why argue about this if you don't even know what the theory predicts and how to use it.
 
Neddy Bate said:
All you are doing is "transforming away" the problem by transforming it back into the train or rod frame.
No, I am not doing any of such.

You are essentially saying that the platform frame should disregard its own clock measurements and use the train's clock measurements instead. The only reason you give for this is because you want the rod to remain parallel in both frames. By definition, that is "transforming the problem away."

If I wanted the rod to be diagonal in both frames, would you let me say that the train frame should disregard its own clock measurements and use the platform's clock measurements instead? If not, then why is one preferred over the other?



Three problems:

1. The paper isn't published
2. No one did the experiment
3. J.H. Field is known as a fringer.

Any experiment which supports length contraction must also support RoS. Consider the situation where the train and the platform happen to be the same length, as measured by the platform frame. This means the endpoints of the train become aligned with the endpoints of the platform simultaneously in the platform frame. Please note that the train is length contracted according to the platform frame, but the platform itself is not length contracted. Now consider the train frame. In that frame, the train is not length contracted, but the platform is! This means the endpoints of the train CANNOT become aligned with the endpoints of the platform simultaneously in the platform frame. Thus RoS occurs wherever length contraction occurs. They are two sides of the same coin.
 
You are essentially saying that the platform frame should disregard its own clock measurements and use the train's clock measurements instead.

No, that is not what I am saying. What I am saying is that only a very opaque person equates different coordinate time labels with a measurable physical effect. Now, please shut up and wait for the continuation of discussion as you promised.
 
There's only one frame in which the measurements are invariant. The local proper frame where the measurements are made. Remote coordinate frame measurements are frame dependent. Make sense? Really. Why argue about this if you don't even know what the theory predicts and how to use it.

Are you saying the platform should not make its own measurements?
 
Back
Top