Discussion in 'Physics & Math' started by timewarp, Oct 22, 2011.

Not open for further replies.
1. ### timewarpRegistered Member

Messages:
30
Why was clock transport "invented"? What is its general purpose?

3. ### MacGyver1968Fixin' Shit that Ain't BrokeValued Senior Member

Messages:
7,028
To prevent clocks from being damaged during a move.

5. ### OnlyMeValued Senior Member

Messages:
3,914
The intent of your question is not clear. What exactly are you asking? What do you mean by clock transport. What is the context?

Are you referring to clock transport as used in the synchronization of clocks or some other situation?

7. ### EmilValued Senior Member

Messages:
2,789
Because not only the manufacturers to have watches.
But how does this with math or physics?

8. ### prometheusviva voce!Registered Senior Member

Messages:
2,045
Is this a relativity question?

9. ### timewarpRegistered Member

Messages:
30
I am not trying to be contentious here, but just trying to defend myself:
This _is_ a physics forum, and if one Googles "'clock transport'" physics,"
then one gets almost nothing but "slow clock transport," "simultaneity."
"synchronization," etc. see tinyurl.com / 3rw9o2e

Anyway, I shall be more than happy to expand re my query.

I gather that clock transport is better if done slowly. Indeed, very slow
transport seems to be the ideal. But this slowness is apparently not the
overall goal, which itself seems to have something to do with clock
synchronization. (The slowness seems to be used only for attenuating
certain "relativistic effects.")

Maybe we can get a clue about the overall purpose by looking at the first
step, or the initial conditions. In every clock transport scenario, two adjacent
clocks are made to read the same time prior to one or both of them being
transported.

From this clue, we can possibly conclude that the purpose of very slow clock
transport is to preserve the initial true (or absolute) synchronization.

Do you (and the other forum folks) agree?

10. ### chingluValued Senior Member

Messages:
1,637
If you assume the truth of SR, then slow clock transport is supposed to maintain the sync time of two clocks of a particular frame, not absolute time.

So, this is not about about absolute synchronization under the rules of SR.

11. ### OnlyMeValued Senior Member

Messages:
3,914
That is an accurate description of the intent of "slow clock transport" in connection with the synchronization of clocks.

Special Relativity, by way of the Lorentz Transformations, says that a moving clock runs slower than a stationary clock. The rate of difference is proportional to the difference in velocity between the two clocks. So synchronizing the clocks and then moving one very slowly preserves the synchronization, as best as possible.

12. ### OnlyMeValued Senior Member

Messages:
3,914
Chinglu, there is no such thing as absolute time! Bringing up that discussion in this context, is not appropriate.

13. ### chingluValued Senior Member

Messages:
1,637

The poster wrote
transport is to preserve the initial true (or absolute) synchronization.

Absolute synchronization involves absolute time. Otherwise, prove your case.

14. ### chingluValued Senior Member

Messages:
1,637
This is science fraud.

I said, "If you assume the truth of SR, then slow clock transport is supposed to maintain the sync time of two clocks of a particular frame, not absolute time.".

As we can see, that is what i said.

Since you are wrong, I expect you to admit it.

15. ### prometheusviva voce!Registered Senior Member

Messages:
2,045
Mod note: chinglu has been banned for 3 days for trolling

16. ### Pincho PaxtonBannedBanned

Messages:
2,387
Well the purpose sounds right to me.

17. ### timewarpRegistered Member

Messages:
30
(To all: Thanks for the replies.)

Just to make sure that we are all on the same page:
Please note that even in relativity all observers agree that two touching
clocks are absolutely synchronized. Of course, as clock transport tells us,
such clocks are useless for event observation because they are no better
than one clock; however, it turns out that said clocks do have a purpose,
one that may not bode well for the future of special relativity: They give
us a simple rule pertaining to touching clocks.

To see what this rule is, let's look at a down-home example:
Suppose you had two clocks sitting side-by-side on your dining room table.
_______________[3pm][7am]_________________
...............................the clocks
Suppose one clock reads three pm, whereas the other reads seven am.
Clearly, this is much worse than the initial stage of clock transport. In fact,
least one of them must be wrong.

Apparently, both the just-given example and clock transport lead to the
following very simple rule: In order to be properly related temporally,
two touching clocks should always read the same time.

Let's try to put this simple rule into action. Suppose a passing light ray
meets (or "hits") two touching clocks; the rule says that these clocks
must then read the same time. Note that this example even emphasizes
the rule by bringing up the fact that a light ray can start two touching
clocks truly simultaneously. (Of course, this does not by any means
give us absolute simultaneity because this calls for two non-touching
clocks that are truly synchronous.)

Does the given rule seem reasonable?

18. ### OnlyMeValued Senior Member

Messages:
3,914
I am not entirely sure what you are doing here!

You begin with two clocks side by side that are not synchronized. For your example to have any meaning at all. The clocks must be synchronized at some point, usually initially.

In most of the hypotheticals I have seen involving a ray of light to synchronize two clocks it is not the ray of light that does the work. The light only provides the marker in time that two observers use to set their clocks to the same time.

BTW Welcome to SciForums...

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

Messages:
10,166
It's awully ironic that chinglu has been banned for being correct for once.
Starting from post 6:

timewarp suggests that slow transport preserves absolute synchronization:
chinglu corrects timewarp:
OnlyMe misunderstands chinglu:
chinglu points out that timewarp brought up absolute time:
...and defends himself against OnlyMe's misrepresentation:
Then prometheus bans chinglu? :bugeye:
Your timing sucks, prometheus. Most of chinglu's posts are blatant trolling, but not this time. Why on earth did you ban him when he's actually making sense?

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

Messages:
10,166
No. As chinglu said, there is no absolute synchronization in SR.
Slow transport preserves relative synchronization.

If the two clocks are initially moving, slow separation of the clocks results in desynchronization.

21. ### OnlyMeValued Senior Member

Messages:
3,914
Pete, I don't think I misunderstood timewarp, I may be wrong, but,

in the above quote I took the use of absolute to be associated with the synchronization of the clocks not their frame of reference, or as denoting any absolute frame of reference for time.

When Chinglu rephrased it it sounded to me as if he shifted the use of the word absolute from the synchronization to a comparrison of relative time and absolute time, as separate frames of reference.

I could have been wrong in how I read the intended meaning in either post, even both posts.

Still, I would not have taken offense personally, either way and had my interpretation been wrong I would have accepted correction.

I think the time out was perhaps a bit hasty myself, also. And perhaps the way I responded to what I thought Chinglu meant, was itself worded badly.

22. ### EmilValued Senior Member

Messages:
2,789
There are two clocks, clock 1 and clock 2.
The two clocks have a relative speed between them.
Question1: at which clock is applied the Lorentz transformation so the two clocks to be synchronous?
Question 2: Lorentz transformation is applied only on the speed direction?

23. ### TachBannedBanned

Messages:
5,265
this question makes no sense.

this question doesn't make any sense either.