Conventionality and clock symchrnization

  • Thread starter bernhard.rothenstein
  • Start date
  • Tags
    Clock
In summary, in relativity discussions "Einstein clock synchronization" is usually simply assumed and the question of different synchronizations is never considered. If someone talks about "conventionality of simultaneity" they are considering which parts of relativity depend on a choice of synchronization convention and which do not.
  • #1
bernhard.rothenstein
991
1
Please tell me if "conventionality of dimultaneity" and "Einstein clock synchronization" are one and the same thing?
Please tell me how could be quoted ideas received on the Forum.
 
Physics news on Phys.org
  • #2
bernhard.rothenstein said:
Please tell me if "conventionality of dimultaneity" and "Einstein clock synchronization" are one and the same thing?
Please tell me how could be quoted ideas received on the Forum.

I guess you mean "conventionality of simultaneity"? If so, no, it is not necessarily the same thing. Einstein's method is one (very good) convention, but I think there are others. Here's a good discussion from http://www.science.uva.nl/~seop/entries/spacetime-convensimul/#Rel".

Jorrie
 
Last edited by a moderator:
  • #3
bernhard.rothenstein said:
Please tell me if "conventionality of dimultaneity" and "Einstein clock synchronization" are one and the same thing?
Please tell me how could be quoted ideas received on the Forum.
In relativity discussions, "Einstein clock synchronization" is usually simply assumed and the question of different synchronizations is never considered. If someone talks about "conventionality of simultaneity" they are considering which parts of relativity depend on a choice of synchronization convention and which do not. Or in the case of the interesting paper quoted by Jorrie, they are considering the philosophical question as to whether or not there is a "natural" synchronization that need not be considered to be a "convention" at all.

Thus you may see statements such as "time dilation and length contraction are conventional" or "the twin paradox has an unconventional solution". The words "conventional" and "unconventional" are being used in an unusual sense here as meaning "dependent on a choice of synchronization convention" or "independent of a choice of synchronization convention".

So the answer to your question is that the two phrases would be used in slightly different contexts. "Conventionality of simultaneity" might often mean "conventionality of Einstein synchronization".
 
  • #4
conventionality

DrGreg said:
In relativity discussions, "Einstein clock synchronization" is usually simply assumed and the question of different synchronizations is never considered. If someone talks about "conventionality of simultaneity" they are considering which parts of relativity depend on a choice of synchronization convention and which do not. Or in the case of the interesting paper quoted by Jorrie, they are considering the philosophical question as to whether or not there is a "natural" synchronization that need not be considered to be a "convention" at all.

Thus you may see statements such as "time dilation and length contraction are conventional" or "the twin paradox has an unconventional solution". The words "conventional" and "unconventional" are being used in an unusual sense here as meaning "dependent on a choice of synchronization convention" or "independent of a choice of synchronization convention".

So the answer to your question is that the two phrases would be used in slightly different contexts. "Conventionality of simultaneity" might often mean "conventionality of Einstein synchronization".

thank you for your answer
please consider the equation
t(E)=t(e)+x/c (1)
where t(E) represents the reading of an Einstein synchronized clock located at point (x,0)
t(e) representing the time when the synchronizing agent, propagating with speed c, was emitted.
The single terms on which conventions could be made are x and c.
-If we consider c=infinity we make the everyday clock synchronization proposed by Leubner and discussed in a previous thread.
-If we consider x=0 we obtain the "inertial transformations Selleri" with time transforming
in accordance with time dilation.
-we make the two way light propagation with c, c(+), c(-) considering even infinite values for the propagation speed of the synchronizing signal.
If the statements made above are correct then my problem is if there are other ways to complete the classification made above.
Regards
 
  • #5
bernhard.rothenstein said:
The single terms on which conventions could be made are x and c.
If you want your coordinates to be physically meaningful (so x is compatible with "proper length") you have no choice over x.

bernhard.rothenstein said:
-If we consider c=infinity we make the everyday clock synchronization proposed by Leubner and discussed in a previous thread.
Yes.

bernhard.rothenstein said:
-If we consider x=0 we obtain the "inertial transformations Selleri" with time transforming
in accordance with time dilation.
No. I dealt with this in this post.

bernhard.rothenstein said:
-we make the two way light propagation with c, c(+), c(-) considering even infinite values for the propagation speed of the synchronizing signal.
Yes (if I understand you correctly). The two way speed of light c must be constant (to agree with experiment and SR), but the one-way speeds c+ and c- can be varied, with different synchronisations. Note that 1/c = (1/c+ + 1/c-)/2 (see this post). In more than one spatial dimension it gets more complicated as the speed of light would vary by direction, but the relation above would still hold for any two opposite directions.

bernhard.rothenstein said:
If the statements made above are correct then my problem is if there are other ways to complete the classification made above.
I think that probably covers it. In the notation of Stanford Encyclopedia of Philosophy - Conventionality of Simultaneity, varying the value of c+ is equivalent to varying the value of [tex]\epsilon[/tex].

Note that, I think, c+ could even vary as a function of position and time, but that would get very complicated to ensure the two-way speed was still constant.
 

1. What is the concept of conventionality in the context of clock synchronization?

The concept of conventionality refers to the idea that the synchronization of clocks is not an inherent property of time, but rather a convention or agreement among observers. In other words, the concept of time and the way it is measured is based on human conventions and does not have an objective reality.

2. How does conventionality affect the synchronization of clocks?

Conventionality affects the synchronization of clocks because it means that there is no standard or absolute way of measuring time. Different observers may have different conventions for synchronizing their clocks, which can lead to discrepancies in time measurements.

3. What is the role of the speed of light in clock synchronization?

The speed of light plays a crucial role in clock synchronization as it is the maximum speed at which information can travel. This means that any attempts to synchronize clocks over long distances must take into account the time it takes for light to travel between the clocks.

4. What is the difference between absolute and relative simultaneity?

Absolute simultaneity refers to the concept of events happening at the same time regardless of an observer's perspective. In contrast, relative simultaneity takes into account the observer's perspective and acknowledges that events may appear simultaneous to one observer but not to another.

5. How does the theory of relativity impact our understanding of clock synchronization?

The theory of relativity has a significant impact on our understanding of clock synchronization as it challenges the notion of absolute time and introduces the concept of time dilation. It also highlights the role of conventionality in clock synchronization and emphasizes the need for a consistent and agreed-upon method for measuring time.

Similar threads

  • Special and General Relativity
2
Replies
39
Views
1K
  • Special and General Relativity
2
Replies
51
Views
2K
  • Special and General Relativity
2
Replies
35
Views
2K
  • Special and General Relativity
Replies
16
Views
612
  • Special and General Relativity
3
Replies
84
Views
4K
  • Special and General Relativity
Replies
21
Views
2K
  • Special and General Relativity
Replies
32
Views
3K
  • Special and General Relativity
2
Replies
51
Views
2K
  • Special and General Relativity
Replies
12
Views
1K
  • Special and General Relativity
Replies
20
Views
746
Back
Top