Clock synchronization process

In summary: That doesn't mean they aren't synchronized as the choice of ##\epsilon## is what defines the synchronization of clocks. The clocks may show different times according to the Einstein synchronization convention but not according to my other choice of ##\epsilon##. None of your objects have anything to do with whether or not...
  • #1
analyst5
190
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This is basically a follow-up to some questions from a previous thread regarding Einstein synchronization and other methods. I don't understand the alternative methods when the synchronization parameter isn't 1/2 and its connection to the speed of light. Basically it means that the light is quicker in one direction than the other, but there are is an infinite number of directions, so I don't understand which light rays are quicker than the others. For instance, let's suppose that we sync two distant clocks with a non-standard method. So the light from the front, in one case, may be faster than the light coming from the back, right? How would the light mentioned in this case behave in other directions regarding its velocity?
 
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  • #2
analyst5 said:
This is basically a follow-up to some questions from a previous thread regarding Einstein synchronization and other methods. I don't understand the alternative methods when the synchronization parameter isn't 1/2 and its connection to the speed of light. Basically it means that the light is quicker in one direction than the other, but there are is an infinite number of directions, so I don't understand which light rays are quicker than the others. For instance, let's suppose that we sync two distant clocks with a non-standard method. So the light from the front, in one case, may be faster than the light coming from the back, right? How would the light mentioned in this case behave in other directions regarding its velocity?

If light "were quicker in one direction than in the other", then there would be no operational way of synchronizing clocks by using light signals. Fortunately, experiment shows that light speed (one way) is isotropic. Even if it weren't, you could still synchronize clocks (via slow clock transport, as they did it for the ill-fated "neutrino faster than light" experiment), you just couldn't use light signals.
 
  • #3
xox said:
If light "were quicker in one direction than in the other", then there would be no operational way of synchronizing clocks by using light signals. Fortunately, experiment shows that light speed (one way) is isotropic. Even if it weren't, you could still synchronize clocks (via slow clock transport, as they did it for the ill-fated "neutrino faster than light" experiment), you just couldn't use light signals.

Is it also isotropical in non-inertial frames, but can have a different value than c?
 
  • #4
xox said:
If light "were quicker in one direction than in the other", then there would be no operational way of synchronizing clocks by using light signals.

Yes there is. One simply uses Grunbaum's ##\epsilon##-synchrony for inertial frames.

xox said:
Fortunately, experiment shows that light speed (one way) is isotropic.

No it doesn't. There is no experiment that can show the one-way speed of light is isotropic in inertial frames. The isotropy of the one-way speed of light in inertial frames is purely a convention.
 
  • #5
WannabeNewton said:
No it doesn't. There is no experiment that can show the one-way speed of light is isotropic in inertial frames. The isotropy of the one-way speed of light in inertial frames is purely a convention.


There is a very large spectrum of tests on OWLS anisotropy, here is a very small sample. I can provide you with many more tests of OWLS anisotropy.
 
  • #6
WannabeNewton said:
Yes there is. One simply uses Grunbaum's ##\epsilon##-synchrony for inertial frames.

While the predictions derived from such departures from Einstein synchronization produce theories experimentally indistinguishable from SR, the defined clock time varies from Einstein's according to the distance in a specific direction.(see Zhang's book). So, in earnest, the clocks aren't synchronized anymore because they show different times.To make matters worse, the difference varies with distance.
 
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  • #7
WannabeNewton said:
Yes there is. One simply uses Grunbaum's ##\epsilon##-synchrony for inertial frames.



No it doesn't. There is no experiment that can show the one-way speed of light is isotropic in inertial frames. The isotropy of the one-way speed of light in inertial frames is purely a convention.


Ok, so if we specify the light speed in one direction and automatically the speed in the opposite direction, how do speeds of light in other directions follow from that?
 
  • #8
analyst5 said:
Ok, so if we specify the light speed in one direction and automatically the speed in the opposite direction, how do speeds of light in other directions follow from that?

Elementary treatments tend to stick to 1-dimensional expositions however the same thing you do for 1-dimension applies to 3-dimensions except now you have to treat 3 independent directions as opposed to just 1.
 
  • #9
xox said:
So, in earnest, the clocks aren't synchronized anymore because they show different times.To make matters worse, the difference varies with distance.

That doesn't mean they aren't synchronized as the choice of ##\epsilon## is what defines the synchronization of clocks. The clocks may show different times according to the Einstein synchronization convention but not according to my other choice of ##\epsilon##. None of your objects have anything to do with whether or not one-way anisotropic speed of light synchronizations are available (and they clearly are).

xox said:
There is a very large spectrum of tests on OWLS anisotropy, here is a very small sample. I can provide you with many more tests of OWLS anisotropy.

Did you read the opening paragraph of the relevant subsection in that link?
 
  • #10
WannabeNewton said:
.
Did you read the opening paragraph of the relevant subsection in that link?

Yes, I am very familiar with the opening paragraph, I know Tom Roberts personally and I pointed out to him, repeatedly, that the way he wrote it it conveys the wrong message. But he is stubborn and he would not change it.
Your objection does not change the fact that there is a large spectrum of OWLS anisotropy tests. Most (if not all) experimentalists would disagree with your statement:

WannabeNewton said:
There is no experiment that can show the one-way speed of light is isotropic in inertial frames.

The test theories that Tom Roberts is talking about are exactly the instruments used to constrain light speed anisotropy. This is a much better way of explaining things than the negative way Tom Roberts wrote it.
 
  • #11
WannabeNewton said:
Elementary treatments tend to stick to 1-dimensional expositions however the same thing you do for 1-dimension applies to 3-dimensions except now you have to treat 3 independent directions as opposed to just 1.


I understand the basic premise of your post, but could you please give some additional details when comparing 1-dimensional analysis as opposed to 3-dimensional sync situation?
 

What is clock synchronization process?

Clock synchronization process is the process of coordinating the time of different clocks in a system to ensure they all display the same time. This is important for systems where accurate timing is crucial, such as in telecommunications, computer networks, and scientific experiments.

Why is clock synchronization necessary?

Clock synchronization is necessary to ensure that all devices in a system are operating on the same time scale. This allows for accurate communication and coordination between devices, as well as preventing errors and discrepancies caused by differences in time.

What are the different methods of clock synchronization?

There are several methods of clock synchronization, including Network Time Protocol (NTP), Precision Time Protocol (PTP), and Global Positioning System (GPS) synchronization. These methods use different techniques to synchronize clocks, such as using a reference time source or exchanging time information between devices.

What are the challenges of clock synchronization?

One of the main challenges of clock synchronization is dealing with network delays and variations in time between devices. This can result in inaccuracies and requires careful calibration and adjustment to achieve precise synchronization. Additionally, security and reliability concerns must be addressed when implementing clock synchronization in critical systems.

What are the benefits of clock synchronization?

Clock synchronization has numerous benefits, including improved accuracy and reliability of time-sensitive systems, better coordination and communication between devices, and prevention of errors caused by differences in time. It also allows for easier troubleshooting and maintenance of systems, as all devices are operating on the same time scale.

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