Does My Wrist Watch Physically Beat Slower?

HallsofIvy

What do you mean by "every earthly second"? That's the crucial point!

Vandam

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

George Wells from Bishop's Stortford?

Vandam

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

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.

If you're going to continue to misunderstand what I say, there's not much point in discussion.

Experimental results are things like those referred to here:

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

I have no idea what you're talking about here. Can you link to the other thread?

Vandam

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

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

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

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

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.

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.

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.

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

O.K. 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. And that's how I read it. I don't agreeThat's very strange because I just all explained it to you... Of course you can calculate it, but it is not independent of any interpretation. dee below.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

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.

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.

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.

It doesn't work for you, perhaps. It works for me just fine.

DaleSpam

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

No, not I.

Vandam

SR with LET interpretation? What is this for nonsense! It's either LET or SR. 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. 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

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.

I disagree; as has been said repeatedly, LET uses the LT, and makes all the same experimental predictions based on it.

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.

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

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.