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Does My Wrist Watch Physically Beat Slower?

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Vandam
#19
Dec27-12, 10:57 AM
P: 126
Quote Quote by PeterDonis View Post
Such discussion is fine, but it's not physics. It's the history of physics. The two are not the same.
Are you telling us here that Einstein's SR didn't contribute anything to physics, but a lot to philosophy?
I explained you elsewhere what Einstein did for physics as far as the Lorentztransformations mations are concerned, but you stay stuck to your calculator. Physics is more than mathematics. But you refuse to accept that.
The Jericho
#20
Dec27-12, 11:03 AM
P: 21
George Wells from Bishop's Stortford?
Vandam
#21
Dec27-12, 11:13 AM
P: 126
Quote Quote by PeterDonis View Post
If experimental results are consistent with more than one interpretation in terms of "physical objects and processes", then the correct answer is that *we do not know for sure* what physical objects and processes there are. I would rather just admit that openly.
What do you call an experimental result? What your calculator tells you?
I asked you to show me an another thread where in the ETHER context you read the primed time coordinates (Lorentz' Local time). You cannot. The numbers of your calculator have to make sense in the physical ether LET, but they don't. Lorentz knew it and admitted it. But you just don't get it.
PeterDonis
#22
Dec27-12, 11:24 AM
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Quote Quote by Vandam View Post
Are you telling us here that Einstein's SR didn't contribute anything to physics, but a lot to philosophy?
Read what I said. I didn't say that. All I said was that the historical development of physics is not the same as physics itself.

Quote Quote by Vandam View Post
Physics is more than mathematics. But you refuse to accept that.
If you're going to continue to misunderstand what I say, there's not much point in discussion.

Quote Quote by Vandam View Post
What do you call an experimental result? What your calculator tells you?
Experimental results are things like those referred to here:

http://math.ucr.edu/home/baez/physic...periments.html

Quote Quote by Vandam View Post
I asked you to show me an another thread where in the ETHER context you read the primed time coordinates (Lorentz' Local time). You cannot. The numbers of your calculator have to make sense in the physical ether LET, but they don't. Lorentz knew it and admitted it. But you just don't get it.
I have no idea what you're talking about here. Can you link to the other thread?
Vandam
#23
Dec27-12, 11:26 AM
P: 126
Quote Quote by HallsofIvy View Post
First wrist watches don't beat! What relativity says is that your wrist watch will run slower, your pulse will be slower, you will move slower, as observed from a frame of reference with respect to which you are moving. Of course, from your point of view that person observing you is moving with respect to you and so you will observe his watch running slower, his pulse beating slower, etc.

Yes, this is a "real" result. It has been, for example, experimentally verified that elementary particles that are moving fast with respect to the laboratory have longer lifetimes than those that are stationary with respect to the laboratory.
Correct.
Just to make sure we agree on 'observe':
The observer observes what the 'time indications on clocks' are, part of his 3D world. The time indications on the clocks are (space-like) events part of the observer's 3D world. The events existed before the observer 'observes' them.
Vandam
#24
Dec27-12, 11:38 AM
P: 126
Quote Quote by PeterDonis View Post
I have no idea what you're talking about here. Can you link to the other thread?
You only keep on telling me that the one coordinates are ether coordiates, the other 'local'.
http://www.physicsforums.com/showpos...&postcount=113

Show me where the local times are in LET.

Tell me what the difference is between ether coordinate and 'the primed coordinate'. Where is that primed coordinate for the traveler in LET? I do not see that. And it is impossible to see it in LET, because it is only a mathematical fictuous number. Einstein solved that problem.
PeterDonis
#25
Dec27-12, 12:03 PM
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Quote Quote by Vandam View Post
You only keep on telling me that the one coordinates are ether coordiates, the other 'local'.
http://www.physicsforums.com/showpos...&postcount=113
That's a post by DaleSpam, not me. I agree with what he said, but if you want someone to expound further on it, you should ask him.
Vandam
#26
Dec27-12, 01:55 PM
P: 126
Quote Quote by PeterDonis View Post
That's a post by DaleSpam, not me. I agree with what he said, but if you want someone to expound further on it, you should ask him.
Sorry about that.

But if you agree with him you might perhaps tell me what the primed coordinates are in LET? What do they mean for the traveler in the ether? His wristwatch time etc.?

Lorentz' quote: <<The chief cause of my failure was my clinging to the idea that the variable t only can be considered as the true time and that my local time t' must be regarded as no more than an auxiliary mathematical quantity. In Einstein's theory, on the contrary, t' plays the same part as t; if we want to describe phenomena in terms of x'; y'; z'; t' we must work with these variables exactly as we could do with x; y; z; t.>>

The best way to understand time coordinates is to synchronise clocks at the 'origin of measurement'. The primed coordinates then are the red wristwatch time and proper measuring stick space coordinates... in his own red 3D world. Not the green 'ether' 3D world. Red traveler has to wait .289 wristwatch time units to have event A in his Spaceworld. You can never get that in a LET scenario. The primed time coordinates (.289,.289) only make sense if you let go the ether. Considering the green ether through red time .289 doesn't make sense for the 0289 space coordinate, because in that ether world event A is not part of that world.
Only in SR it makes sense if you consider a real 3D world through event A and red .289 wristwatch time. And that tells you that the event A is considered in a green future world for Mr Green, but is already real in the present red world for Mr Red. Block universe, whether you like it or not...
Or do you have another scenario for Mr Red and his time coordinate?


@Kingfire
To link the above to the opening post:
Below I quickly sketched a Loedel diagram for the same LT coordinates. You see that neither the red nor the green worldline is stretched (and definitely not contracted either): In 4D spacetime the spacing of the time units are equal on all worldlines. Proper time is never dilated.
Time dilation occurs because of the different directions of 3D worlds of simultaneous events in 4D block spacetime.
The time indications on the clocks are events that have fixed locations in 4D block universe, but because of the different directions of worldlines in 4D space, the traveler events of the respective worldlines will have other (pre-existing) 'clock with time indication' event in their respective 3D worlds.
(Note: the 3D worlds with their -obviously space-like) clock events are already 'out there' in 4D block spacetime before the 'observer' literally sees the clock events. (A 'lichtcone' scenario only tells you wich events have a possible causal relationship with your 'now' event'. But that's not important in this topic)
PeterDonis
#27
Dec27-12, 02:13 PM
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Quote Quote by Vandam View Post
But if you agree with him you might perhaps tell me what the primed coordinates are in LET?
I'm not an expert on LET so I don't know if I can answer this; but as I understand it, the convention in LET is to write coordinates in the "ether frame" as unprimed, and coordinates in any other frame which is moving relative to the ether as primed. So if some observer is moving relative to the ether, the coordinates in the frame in which that observer is at rest would be written as primed coordinates.

Quote Quote by Vandam View Post
What do they mean for the traveler in the ether? His wristwatch time etc.?
Since the observer is at rest in the primed frame under this convention, t' would be the same, numerically, as proper time as measured by the observer, which you appear to refer to as "wristwatch time". But there is still a logical distinction between the *coordinate* time, t', which is a number assigned to an event, and the *proper* time of the observer, which is something he directly observes.

Quote Quote by Vandam View Post
Lorentz' quote: <<The chief cause of my failure was my clinging to the idea that the variable t only can be considered as the true time and that my local time t' must be regarded as no more than an auxiliary mathematical quantity. In Einstein's theory, on the contrary, t' plays the same part as t; if we want to describe phenomena in terms of x'; y'; z'; t' we must work with these variables exactly as we could do with x; y; z; t.>>
As far as I can tell, what Lorentz meant here was that he treated the "ether frame" as being somehow special, physically, whereas Einstein did not; Einstein treated all inertial frames as physically equivalent. So for Lorentz, the coordinate time in the ether frame had a special physical status, as "true time"; the coordinate time in any other frame did not. Einstein made no such distinction. That's how I read it, anyway.

However, none of that makes any difference as far as the diagrams you are talking about. See below.

Quote Quote by Vandam View Post
You can never get that in a LET scenario. The primed time coordinates (.289,.289) only make sense if you let go the ether.
I don't see how this follows at all. You can calculate the primed time coordinates in the ether frame just as well as in any other frame. You can also predict that that primed time coordinate will be numerically equal, as I said above, to the proper time measured by the observer at rest in the primed frame. All that is independent of any "interpretation".

LET makes different assertions about the underlying "physical reality" than the "block universe" interpretation does, but the primed time coordinate, in itself, doesn't necessarily say anything about underlying physical reality; it just enables us to predict a particular observed quantity, the "wristwatch time" of an observer at rest in the primed frame. So the second statement of yours in the quote just above is not correct as you state it: a correct statement would be "the primed time coordinates only make sense according to the block universe interpretation if you let go the ether".
Vandam
#28
Dec27-12, 02:38 PM
P: 126
Quote Quote by PeterDonis View Post
I'm not an expert on LET so I don't know if I can answer this; but as I understand it, the convention in LET is to write coordinates in the "ether frame" as unprimed, and coordinates in any other frame which is moving relative to the ether as primed. So if some observer is moving relative to the ether, the coordinates in the frame in which that observer is at rest would be written as primed coordinates.
O.K.

Since the observer is at rest in the primed frame under this convention, t' would be the same, numerically, as proper time as measured by the observer, which you appear to refer to as "wristwatch time". But there is still a logical distinction between the *coordinate* time, t', which is a number assigned to an event, and the *proper* time of the observer, which is something he directly observes.
O.K., but there is no distinction if you synchronise the clocks as I did.
I can give you an example if you use time-coordinates that give different numbers as the clock time indications of the events the observer reads, but that makes no difference. I makes it only more fifficult for the forum members to follow.


As far as I can tell, what Lorentz meant here was that he treated the "ether frame" as being somehow special, physically, whereas Einstein did not; Einstein treated all inertial frames as physically equivalent. So for Lorentz, the coordinate time in the ether frame had a special physical status, as "true time"; the coordinate time in any other frame did not. Einstein made no such distinction. That's how I read it, anyway.
And that's how I read it.

However, none of that makes any difference as far as the diagrams you are talking about.
I don't agree
See below.

I don't see how this follows at all.
That's very strange because I just all explained it to you...
You can calculate the primed time coordinates in the ether frame just as well as in any other frame. You can also predict that that primed time coordinate will be numerically equal, as I said above, to the proper time measured by the observer at rest in the primed frame. All that is independent of any "interpretation".
Of course you can calculate it, but it is not independent of any interpretation. dee below.

LET makes different assertions about the underlying "physical reality" than the "block universe" interpretation does, but the primed time coordinate, in itself, doesn't necessarily say anything about underlying physical reality; it just enables us to predict a particular observed quantity, the "wristwatch time" of an observer at rest in the primed frame. So the second statement of yours in the quote just above is not correct as you state it: a correct statement would be "the primed time coordinates only make sense according to the block universe interpretation if you let go the ether".
I can not agree with that. Lorentz admitted that the 'true time' and the 'local time' have to be treated ('interpreted' if you like) the same way. Only SR does that. Not LET. That's the whole point in the SR versus LET. If there would be no difference there would be no Einstein, nor SR.

You would be correct it you compare Galilean transformation and ether world. After transformation you no not have to drop the 'Newton' ether to make sense of the transformation coordinates. But with Lorentz Transformation that doesn't work.
PeterDonis
#29
Dec27-12, 03:53 PM
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Quote Quote by Vandam View Post
O.K., but there is no distinction if you synchronise the clocks as I did.
Please read carefully. I said a *logical* distinction, not a *numerical* distinction. I agree that, given your synchronization of clocks, there is no numerical distinction. But there *is* a logical distinction.

Quote Quote by Vandam View Post
That's very strange because I just all explained it to you...
You have not "explained" anything. You have continued to point out features of spacetime diagrams, relativity of simultaneity, etc. that we all understand and all agree on. You have *not* given any argument for how those features *require* a "block universe" interpretation. You have only argued that a block universe interpretation is consistent with them. That's not sufficient to justify the claims you have made.

Quote Quote by Vandam View Post
Lorentz admitted that the 'true time' and the 'local time' have to be treated ('interpreted' if you like) the same way. Only SR does that. Not LET.
When Lorentz made that statement, *not one single actual prediction changed*. What you are calling "SR" (which should really be called "SR with the block universe interpretation") and what you are calling LET (which should really be called "SR with the LET interpretation") make exactly the same predictions for all experimental results.

Your claim appears to be that we can somehow know which interpretation is correct without any experiment that can decide between them. My claim is that if two interpretations agree on all experimental results, *we do not know* which one is correct, unless and until we can find an experiment that gives different results depending on which interpretation is correct.

Your claim appears to be that we have some knowledge of "physical reality" that doesn't come to us through experiments. My claim is that we don't; obviously the content of our knowledge is more than just a list of experimental results, but our justification for making *any* claim about "physical reality" ultimately has to come down to some piece of knowledge that we got from experiments. If we can't decide between different claims about physical reality by doing an experiment, then we can't decide.

I don't see any prospect of coming to agreement on these claims, but I think I've captured them reasonably well.

Quote Quote by Vandam View Post
After transformation you no not have to drop the 'Newton' ether to make sense of the transformation coordinates. But with Lorentz Transformation that doesn't work.
It doesn't work for you, perhaps. It works for me just fine.
DaleSpam
#30
Dec27-12, 04:32 PM
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Quote Quote by Vandam View Post
You only keep on telling me that the one coordinates are ether coordiates, the other 'local'.
http://www.physicsforums.com/showpos...&postcount=113
I would certainly be glad to continue that discussion in the other thread if you feel that you are sufficiently prepared to discuss it now. However, you did leave in a pretty big huff so I thought you would probably just want to drop it. Either way is fine by me.
ghwellsjr
#31
Dec27-12, 04:38 PM
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Quote Quote by The Jericho View Post
George Wells from Bishop's Stortford?
No, not I.
Vandam
#32
Dec28-12, 02:46 AM
P: 126
Quote Quote by PeterDonis View Post
and what you are calling LET (which should really be called "SR with the LET interpretation")
SR with LET interpretation? What is this for nonsense! It's either LET or SR.
make exactly the same predictions for all experimental results.
You simply do not get the essence. The experimental results (which will confirm the LT calculations) are not possible in a LET context. They only make sense in a 4D block Spacetime. see below.
It doesn't work for you, perhaps. It works for me just fine.
If it works for you, please tell me what the primed space coordinates are. In LET there is no space between event R and A ! Only in SR there is space between event R and A, because in SR events A and R are part of the 3D world through event A and R.
I am really sorry if you do not get that.

Note. I can imagine one reason why you (and Dalespam for that matter) do not understand the difference between SR and LET. Maybe it's because you deny the existence of 3D space out there. Are for you the LT just mathematical interpretations of your mental solipsist bubble? Please confirm this if this is the case. Then I know I do not have to waste time here.
PeterDonis
#33
Dec28-12, 08:45 AM
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Quote Quote by Vandam View Post
SR with LET interpretation? What is this for nonsense! It's either LET or SR.
The math and the experimental predictions are the same either way; that's the point I was making. We can call them Ping and Pong for all I care; that's a matter of nomenclature, not physics.

Quote Quote by Vandam View Post
The experimental results (which will confirm the LT calculations) are not possible in a LET context.
I disagree; as has been said repeatedly, LET uses the LT, and makes all the same experimental predictions based on it.

Quote Quote by Vandam View Post
In LET there is no space between event R and A !
I don't understand where you are getting this from. LET draws exactly the same spacetime diagram as you have drawn, and predicts all of the same numbers. If you think "LET" says anything different from your diagram, then you mean something different by "LET" than the rest of us do. By "LET" the rest of us mean all of the standard math and spacetime diagrams in SR, but with Lorentz's original interpretation in which one inertial frame is labeled as "the ether frame" and given a special significance. That "LET" agrees with your diagram.

Quote Quote by Vandam View Post
I am really sorry if you do not get that.
I am really sorry if you do not get what "LET" the rest of us have been talking about. If you know of some version of "LET" that makes different experimental predictions from what you call "SR", then that "LET" is irrelevant to this discussion. The only "LET" that the rest of us even care about here is the one that makes all the same experimental predictions as "SR" does. And that LET agrees with your diagram; *any* interpretation that makes all the same experimental predictions as "SR" agrees with your diagram.

I won't bother commenting on the rest of your post; if you can't even use the term "LET" the same way the rest of us are, there's no point in discussion.
DaleSpam
#34
Dec28-12, 09:04 AM
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Quote Quote by Vandam View Post
Are for you the LT just mathematical interpretations of your mental solipsist bubble? Please confirm this if this is the case. Then I know I do not have to waste time here.
You have a serious obsession with solipsism. I am not a solipsist, if you believe that I have EVER made statements indicating that then please point them out and I will retract or explain them.

Otherwise then you seem to be under some strange sort of McCarthy-esque paranoia, except that you see solipsists behind every corner instead of communists.
Vandam
#35
Dec28-12, 10:41 AM
P: 126
Quote Quote by PeterDonis View Post
I don't understand where you are getting this from. LET draws exactly the same spacetime diagram as you have drawn, and predicts all of the same numbers. If you think "LET" says anything different from your diagram, then you mean something different by "LET" than the rest of us do.
My diagram shows perfectly what LET means. In my diagram the ETHER frame is very well indicated. In that ether frame the primed coordinates do not make sense, unless they are mathematical fictous ad hoc numbers, just like Lorentz admited himself.
The only thing you can repeat is that the numbers are what they are. Of course. But apparently you can not give me the context in which the numbers make sense.
Only if on that diagram red 3D spaces are added the coordinates make sense.
I see that you do not understand this and there is not much more I can do about it. We better stop arguing about this. It doesn't help either way.
ghwellsjr
#36
Dec28-12, 11:54 AM
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Quote Quote by bobc2 View Post
Quote Quote by Kingfire View Post
Hello,

Some physics books tend to say that "your wrist watch will be beating slower when you travel at the or close to the speed of light." Does that mean literally?

My own speculation:

Although time does slow down when I travel at a speed close to the speed of light, my wrist watch will not beat any faster or slower because it is just a mechanical device that beats every earthly second.

I am not sure though.
Kingfire, there are at least two different competing interpretations of special relativity on this forum.

1) First, there is what is known as the Lorentz Ether Theory (LET). If you are basing the answer to your question on this interpretation, the answer to your question would be, yes. Yes, your watch physically beats slower. That's because, according to LET, there are time shifts in the transmittal of electrical forces between and within physical objects, resulting in actual changes in speeds of physical interactions, including clock mechanisms (affecting tick rates, etc.).
The answer under any interpretation or understanding of any form or version of LET, past or present, is not yes. Even though Lorentz believed in a literal ether defining an absolute rest state, only in which light propagates at c, he, and all other LET adherents never claimed that the earth was ever stationary in it.

Therefore, since the earth must be traveling at some unknown speed and in some unknown direction through the ether, clocks on the earth are already beating slower than the presumed absolute time defined by the ether. So if you take off from the earth in the same direction that the earth is traveling through the ether, then your wristwatch will beat out seconds more slowly than earthly seconds. However, if you take off in the opposite direction, you could actually be stationary in the ether, in which case your wristwatch will beat out seconds faster than earthly seconds.

So the correct answer according to LET is: "unknown".

I already gave the correct answer under SR in my first post.


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