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1) There is a difference between the explicit assumptions that Einstein starts with and the tacit assumptions required for the interpretation to be considered valid.
2) If something cannot be verifiied empirically but it forms part of your conclusion, then it is assumed to be true.
Creationists employ this sort of reasoning to support their claims about God.
It is Alice's assumption that her clocks, in her own frame, are in sync - add all the qualifications in the world you like - which is rendered unjustified by the totaity of empirical observations.
The evidence presented by Bob contradicts this assumption because the evidence presented by Bob shows that the clocks didn't sync.
the empirical observations that he has made show him that the clocks are not in sync.
Does Bob agree that Alice's clocks are in sync "in her own co-ordinate system"? Well, if he quotes the Book of Revelation Relativity and the Gospel according to Einstein: "Blessed are those who believe without seeing", then yes, he agrees with Alice's claims. But he doesn't do so on the basis of any empirical observations that he has made.
Alice devises a method of verification for her claim that the LNM is in the lake. Her verification method says:IF the LNM is in the lake then, IF it breathes, we will see bubbles on the lake. Alice sees Bubbles on the lake and concludes that the LNM is there, even if she hasn't observed the LNM.
The empirical verification that you point to only works IF we assume the clocks are already in sync and IF we assume the one-way speed of light is isotropic.
This is further illustrated by presence of alternative interpretations which return the same empirical values from different starting conditions - conitions under which the clocks are not in sync and the one-way speed of light is not isotropic.
Quote from: HalcYou need to name the assumption that is the same as the conclusion. Without that, there is no circularity, only A that leads to B without any additional assumptions. B doesn't lead back to A. Show me a circle, or your claims of this circularity are empty.Einstein's conclusion is that simultaneity is relative. That is, that events which are simultaneous in one frame are not simultaneous in relatively moving reference frames
You need to name the assumption that is the same as the conclusion. Without that, there is no circularity, only A that leads to B without any additional assumptions. B doesn't lead back to A. Show me a circle, or your claims of this circularity are empty.
The simultaneity of spatially separated events (in any frame) cannot be determined empirically.
The alternative interpretations are based on the exact same empirical obervations but they have Alice's clocks not being synced in her own frame.
Quote from: HalcYou're suggested discarding the constant light speed premise as well.Not necessarily discarding it, rather replacing or reinterpreting it:not that the round-trip speed of light is a constant relative to all inertial frames,but rather that the round-trip speed of light is a constant as measured within all inertial frames
You're suggested discarding the constant light speed premise as well.
Quote from: HalcNot an assumption. That is necessary given constant light speed.The isotropic one-way speed of light is an assumption bcos it has not been - and possibly cannot ever be - measured.
Not an assumption. That is necessary given constant light speed.
Given that we can specify different intial conditions and derive a contradictory - yet empirically equivalent - condition (tB - tA = t' A - tB = non-synced clocks), this demonstrates that the "empirical verification procedure" cannot distinguish between synced clocks (with an isoptropic one-way speed of light) and unsynced clocks (with an isotropic round-trip speed of light).
That means that the evidence does not distinguish between the two. Given that they are contradictory interpretations, this demonstrates that - at least one of them - must be assuming its conclusions bcos both cannot be correct.
Quote from: HalcHis experiment can be reproduced today with modern measuring devices.What are the results of these modern day measurements and can you provide peer** reviewed papers that demonstrate that these measurements represent empirical verification of STR?
His experiment can be reproduced today with modern measuring devices.
I'm sure you realise that such a paper would be pretty big news, so if such exists you shouldn't have much trouble finding it.
I don't need to know all of the reasons why it can't be done.
The onus is on you to demonstrate how it has been done.
If you wish to adopt the position that those peer** reviewed papers are incorrect, go right ahead.
But, just for your benefit, one of the reasons why it would appear that it cannot be measured accurately is because a "common time" would need to be defined at two spatially separated locations.
Quote from: Halc Suppose light moved at thrice the speed in one direction as the other. Wouldn't Roemer see triple the time if he did the experiment in one direction as the other?Unlikely given that the sensitivity of such a one-wway measurement is "2000 times" more sensitive than that of a two-way measurement, and I don't think his equipment was up to it. I'm not sure modern equipment is up to it yet.
Suppose light moved at thrice the speed in one direction as the other. Wouldn't Roemer see triple the time if he did the experiment in one direction as the other?
The other paper I quoted - which supports your position - also makes reference to other issues that need to be accounted for like measurements taken over a longer period of time, seasonal efects, etc.
I just know that the 75%-accurate measurement of the speed of light made in the 1600s isn't an empirical verification of Einstein's interpretation of relativity.
I chose to address it in a different manner by referencing peer** reiewed literature from this aeon. I even referenced literature that attempts to make your case, so as not to be biased.
If you wish to adopt the position that Rømer's measurement is an empirical verification of Einstein's theory
or if you want to adopt the position that the one-way speed of light has been measured in such a way as to conclusively distinguish between the competing interpretations of the evidence
She lives in the SR world, be it valid description of our universe or not.
Everybody has assumed the premises of SR and nothing else. Sure, somebody else making different assumptions might assume that her clocks are not in sync
I bet a non isotropic SoL interpretation could be driven into self contradiction.
You had to violate the premises of SR to do it, rendering the example irrelevant to SR definitions. Alice is assuming those premises, not the conclusion that she demonstrates.
Here's the problem. You're stuck arguing against the same strawman.
Quote from: Halc She lives in the SR world, be it valid description of our universe or not....Everybody has assumed the premises of SR and nothing else. Sure, somebody else making different assumptions might assume that her clocks are not in sync...You had to violate the premises of SR to do it, rendering the example irrelevant to SR definitions. Alice is assuming those premises, not the conclusion that she demonstrates.You keep harping back to the idea that Alice is an SR girl, in an SR wo-orld....wrapped in plastic, life's fantastic (you're better off if you don't get the reference!).
She lives in the SR world, be it valid description of our universe or not....Everybody has assumed the premises of SR and nothing else. Sure, somebody else making different assumptions might assume that her clocks are not in sync...You had to violate the premises of SR to do it, rendering the example irrelevant to SR definitions. Alice is assuming those premises, not the conclusion that she demonstrates.
You keep saying that she and "everybody" has assumed the premises of SR. The problem with that is, NO THEY HAVEN'T!
I will repeat again: I AM NOT ATTEMPTING TO DEMONSTRATE AN INCONSISTENCY WITHIN SR!!*
Given the similarities to the "usual" arguments (of "my peers")
given that SR has now become pretty much intuitive for you, your intuitive response is to deploy the same arguments in the assumption that they address the issue. In this case, however, they don't.
The fact is, neither Alice nor Bob know if they live in an SR world
What I am doing is playing the competing theories off against each other, holding them up against each other and seeing what we can deduce.
Now, given that there are key elements between the interpretations which are mutually exclusive,
but based on the same empirical evidence, it tells us that:a) the interpretations cannot both be true
b) therefore, the empirical evidence cannot verify both interpretations
c) therefore, the same empirical evidence cannot verify the mutually contradictory conclusionsd) therefore, one (or both) of the interpretations must be assuming the validity of their conclusions.
e) One of the mutually exclusive elements pertains to the synchrony of Alice's clocks.
f) therefore, one (or both) of the interpretations must be assuming the conclusion as it pertains to clock synchronisation.
*forgive the all caps sentence. I read in Daniel Kahneman's Thinking fast and slow that statements tend to be remembered better when they are in clear font
Quote from: the_roosh on 07/07/2019 12:59:22Here's the problem. You're stuck arguing against the same strawman.Strong words from the guy that regularly has Alice and Bob making claims that they don't.My quotes you selected just above contradict your assertion. I said somebody else is quite capable of making different assumptions, thus drawing different conclusions. All my conclusions are contingent on the premises of SR. I am not asserting that those premises must be true.Your accusation of strawman fallacy fall flat. At no point do I make a claim about some interpretation or fact that is inconsistent with that interpretation or fact. You on the other hand do this regularly when you have Alice making claims that do not follow from the SR premises.I didn't say they did. I said they assumed it. Everybody is entitled to their interpretation, and Alice/Bob chose that one. Charlie and Dave can be the absolutists in the same scenario if you like, and you're free to express their conclusions as well. Best off if you are explicit about their premises. I gave my absolutist premises, but I'm not sure if they're the official ones.
I am rubber and you are glue. Get that reference?
I mention the usual arguments because all your ideas seem to come from such sites, and none from yourself. You've given me almost no evidence that you're capable of your own thought. The one-way measurement of the speed of light thing is something I've harped on because it showed that fact to me clearly. You run from it because despite it being a really simple case that doesn't threaten any alternate interpretation, you lack the ability to express the scenario in the interpretation of your choice. You cannot find discussion about the scenario on the denial sites from which your arguments are provided.
This statement seems to contradict the thing you did in all caps up there. If you mean the thing in caps, stop implying that SR does not address certain issues.
Not disagreeing, but I actually find very little of that. So name a couple.
I question this one. If you add a 4th premise of a preferred moment, which would be ontologically incompatible with a 4th premise asserting the lack of one, but AFAIK, neither interpretation necessitates the preferred moment premise. A lot of the 'denial' sites have members that make exactly that assertion, so it isn't uncommon.
Quoteb) therefore, the empirical evidence cannot verify both interpretationsHow does that follow from (a) even if I accept (a)? Theories don't get verified by evidence. They get verified by not being falsified by evidence. So you should instead say that b) Empirical evidence cannot falsify either interpretation. This is true by definition. If there was an empirical difference between the two, they would be alternate interpretations. They'd be alternate theories.
Quotec) therefore, the same empirical evidence cannot verify the mutually contradictory conclusionsd) therefore, one (or both) of the interpretations must be assuming the validity of their conclusions.Nonsense. Each interpretation must assume its own premises, but not the validity of them. The validity must be put to the test. If it fails the test, then the interpretation cannot correspond to reality.
Neither interpretation assumes its conclusions. They all assume only their premises. You continue to make this mistake over and over.
Einstein,as I noted earlier, was happy to treat that proposition as true by definition. But the principle of the constancy of the one-way speed of light is not a very plausible candidate for an analytic truth,and it is not surprising that many later physicists and philosophers have sought for ways to put that principle to the test of experiment. As noted earlier, however, no one as yet appears to have described an experiment which could be used to determine the one-way speed of light,and which is such that different results would be compatible with the part of the Special Theory of Relativity that is independent of the one-way velocity principle. So one can say,at the very least, that standard formulations of the Special Theory of Relativity involve an assumption for which,more than ninety years after Einstein's formulation of the theory,there is absolutely no experimental support. The fact that the modified theory* does not entail the One-Way Light Principle would seem to be a reason,therefore, for preferring it to standard formulations of the Special Theory of Relativity—though not,of course, to formulations of the ∈-Lorentz variety.
This is the problem. You're saying that Alice and Bob assume the premises of SR. From that starting point you are defending the self-consistency of SR.
With regard to the absolutists, we don't need to change to Charlie and Dave, we can stick with Alice and Bob and say that they start from absolutist premises
and from there demonstrate the self-consistency of such an interpretation.
As I said, Alice and Bob do not know which type of world they live in, and so they assume neither.
They simply carry out the experiments and then employ an Edward de Bono-like method of analysis of the empirical observations. They see that there are a number o different possible interpretations of the empirical results and so they carry out a cross-comparison to see if they can make any further deductions.
They see that, according to one interpretation their clocks are synced
while according to another [interpretation] their clocks are not synced.
The same empirical evidence fits both interpretations so, the empirical evidence doesn't falsify either - but both cannot be true bcos they are mutually exclusive.
b) I find the best way to test your ideas is against the strongest possiblle opposition
You might find it hard to believe that people can independently arrive at the same conclusions about relativity, but if you bear in mind that, for the vast majority of people, Special Relativity is counter-intuitive, then you would realise that everyone starts from a position where SR is not accepted.
And that is the problem. You are deploying the usual arguments because you are arguing against a strawman, as you have repeatedly demonstrated by presupposing that I am attempting to demonstrate an inconsistency within SR.
With regard to the Romer point. I genuinely don't know what your intention is with that point.
Not bcos it isn't in the manual for how to respond to the arguments of Einsteinian Relativists that "my peers" have clearly given me - the manual is part of the starter pack when you join the mailing list (the t-shirt and hat have to be paid for).
I've got an idea. Why don't we jump on over to Physics Forums and you can start a thread there with the point you are trying to make and we can see what "your peers" have to say about it.
Maybe they will put it in such a way that its relevancy to this discussion becomes clear.
Quote from: HalcNot disagreeing [that there are key elements between the interpretations which are mutually exclusive], but I actually find very little of that. So name a couple.Oh, I don't know, the idea that simultaneity is reltive maybe.
Not disagreeing [that there are key elements between the interpretations which are mutually exclusive], but I actually find very little of that. So name a couple.
The interpretations of length contraction and time dilation are also mutually exclusive.
Simultaneity cannot be both relative and absolute.
To parrotphrase Daniel Kahneman in Thinking, fast and slow a statement that can explain two contradictory outcomes explains nothing at all; evidence that verifies (by way of not falsifying) two contradictory propositions verfies neither.
When two contradictory propositions pass the same test, then the test has verified neither bcos it has not falsified one over the other.
The assumptions being made are empirical assumptions.
They are assumptions about the configuration of the physical system for which there is no empirical evidence.
A theory which includes an assumption about the one-way speed of light
carries with it an implicit (or tacit) statement about the configuration of a physical system i.e. a prediction; it is a prediction which cannot be verified experimentallly and so it represents an empirical assumption i.e. an assumption about the configuration of the physical system.
Contrast this with an interpretation which doesn't include that assumption but is based rather on the empirically determined round-trip speed of light. This interpretation doesn't imply, tacitly or otherwise, the same statement about the configuration of the physical system i.e. it doesn't make the same untestable prediction. It therefore makes fewer assummptions about the physical system and doesn't assume that part of its conclusion.
allow me to quote from Michael Tooley's Time, Tense, and Causation. ...I'll allow you to draw your own conclusions.QuoteThe fact that the modified theory* does not entail the One-Way Light Principle would seem to be a reason,therefore, for preferring it to standard formulations of the Special Theory of Relativity—though not,of course, to formulations of the ∈-Lorentz variety."
The fact that the modified theory* does not entail the One-Way Light Principle would seem to be a reason,therefore, for preferring it to standard formulations of the Special Theory of Relativity—though not,of course, to formulations of the ∈-Lorentz variety."
Bold is mine. Now, I know that you're just itching to isolate the emboldened part and tell me how you don't disagree with this and that it is the premise upon which the theory is based and the conclusions are derived from this, but we can extrapolate from there to show the further tacit, empirical assumptions that the interpretation entails.
The clock synchronisation convention establishing by definition that the time for a light signal from A to B is equal to that of B to A can be restated as, the simultaneity of clock synchronisation events is established by definition. I know, I know, Einstein doesn't say it like this, but that's the beauty of logic, we can deduce it. In assuming that the time from A to B is the same from B to A so the simultaneity of the clock synchronisation events are assumed along with it.
So, given that there is "absolutely no experimental support" for the assumption that the time from A to B equals the time from B to A, there is, by definition, "absolutely no experimental support" that the clocks are synchronised.
If there is absolutely no experimental support then it can only be an empirical assumption.
Similarly, the circularity claim you repeat, when SR is not circular. It does not assume its conclusions nor does it conclude any of its premises. Either of those would be an example of circularity, yes, but it doesn't do either of them. Your argument commits the strawman fallacy when you assert that RoS is assumed for instance. It isn't. Read the paper. It is derived. It follows from the premises.
Fine. Alice still shows that her clocks are synced in her frame, even if that statement is not one of being actually synced in an absolute interpretation. She never claimed the clocks were actually synced. OK, she did assume isotropy to make her claim. If she can't assume that, there's really nothing that can meaningfully be known about the relative state of a pair of clocks, so there's no point in doing a procedure involving them.
And they can't get further, can they?
In no known interpretation do they see that. Not even in your funny one.
That also has not been determined. In any interpretation, they don't know if the pair of clocks is synced. If the results were different, then not-in-sync could be known in some interpretations, but not the results you describe in the experiments they ran.
QuoteThe same empirical evidence fits both interpretations so, the empirical evidence doesn't falsify either - but both cannot be true bcos they are mutually exclusive.I don't know is mutually exclusive with I don't know? I don't think so. I maintain that the isotropic interpretations might both be true.
Oh, I don't know, the idea that simultaneity is reltive maybe.
That's an empirical claim. So the Hafele–Keating experiment is predicted to have different results in a different interpretation. Sure you want to go with that?
This is a rule for theories, yes. No so for interpretations. This is a lot of the reason why physics courses in college don't dwell on interpretations. Take a QM class if you don't believe this. They might touch on the interpretations, but debating them explains nothing at all. The class focuses on empirical facts.
Again, verification consists of inability to falsify. Passing all tests is part of that. If two both pass the test, then neither is falsified by that test, but might be falsified by some other test. Falsification isn't something that is done one over the other. Both interpretations might get falsified by a single test.No interpretatoin/theory is ever fully verified since there always might be a new test someday that falsifies it. The standard relative and absolute interpretations have both yet to be falsified, but SR does have an asterisk that it is only for a special case that only occurs locally in the universe. I found that it also works at the largest scales (where space once again becomes flat), but not on the scales in between.
You seem to be talking about the interpretations now. Yes, the interpretations make some physical assumptions like actual constant light speed for instance, not just empirically constant measurements. If you consider that to be a configuration, then you can call it that. If you say that any interpretation makes any mention of a specific physical system, I deny that. No such premise is made.
Nonsense. An empirical assumption is about what can be tested, and that assumption cannot be tested. Any assumed configuration of the physical system is a metaphysical assumption, not an empirical one. Learn the meaning of the terms.
You don't seem to have expressed any ideas. The whole thread has been what I take to be false statements being made about the relative interpretation, such as it assuming its conclusions. All such statements have been refuted.My examples have not been refuted. Not saying I'm right about them. They can be refuted. You just don't seem up to the task on your own.It's a really simple case that came up due to the usage of a different sync convention than the one Einstein uses. But your reaction to it made it into a little test to see if you can think through a simple scenario on your own. So far I've not seen you do it.
What would I say? They did this thing, and I agree that they did it. How is that possible?Pretty lame thread.
What is relevant to this thread? You're certainly not going about pushing your new interpretation. Haven't heard a word of it. Just pages of asserting that the one interpretation is not the only valid one, and nobody has disagreed with that. Why the continued discussion if nobody has disagreed with this 2nd point you're supposedly trying to make?I'm in it because you're having Alice making strawman conclusions like "the relative interpretation says my clocks are in sync".
My defense of SR rests on its lack of being falsified. What Alice and Bob are doing is irrelevant to that unless what they actually conclude (not your strawman conclusions) is found to be in contradiction with the premises of SR.
I am pointing out the statements that I feel are doing just that. You making those statements makes my claims actual, not strawman.
You joke, but its real. There's quite an industry set up to separate this crowd from their money, same as it done for any fanatic group. The religions don't have a monopoly on doing that. OK, they do if you consider it a religion, which it probably is since the sites are often religion based. Apparently Einstein and God have become mutually exclusive, despite my school teaching the exact opposite.
Shall we do that? It might be instructive. Alice is in the stationary system, but it hasn't been specified if she knows that. If she doesn't know, then her clocks are synced but she has no no way to determine that. Bob once again agrees with everything and makes no contradictory conclusions.
What's the point? I never said it wasn't. Einstein's sync convention still works even. It doesn't with your non-isotropic interpretation, but that's a third (unverified) interpretation.
I can't think of an interpretation that doesn't, but I agree that it is an assumption. I am unconvinced that an interpretation with light moving at not-c would be valid. I don't know of one that has been validated.That said, the theory (not any interpretation) does not make this assumption. The theory defines the empirical tests, and those don't rely on any assumption of one-way SoL. If they did, there wouldn't be all these sites saying it cannot be measured, would there?
No metaphysical assumption is testable, so none of them are predictions at all. Just assertions. An interpretation that doesn't posit constant light speed indeed doesn't make the same metaphysical statements. It makes damn few as a matter of fact. The theory proper is like that. It makes damn few such assumptions about the physical system.In case you don't see it, I'm agreeing with you. An interpretation that goes light on the assumptions is open to anything, but it also concludes little more than does the theory proper.
Quote from: Halc on 07/07/2019 22:46:28QuoteThe fact that the modified theory* does not entail the One-Way Light Principle would seem to be a reason,therefore, for preferring it to standard formulations of the Special Theory of Relativity—though not,of course, to formulations of the ∈-Lorentz variety."My conclusion is bias (see my bold). If both formulations of the SToR posit this One-Way Light Principle, why does the inability to measure it have any weight in the choice of one formulation (interpretation) over the other?
QuoteThe fact that the modified theory* does not entail the One-Way Light Principle would seem to be a reason,therefore, for preferring it to standard formulations of the Special Theory of Relativity—though not,of course, to formulations of the ∈-Lorentz variety."
I agreed with (and didn't bother to keep) the part you bolded. I agreed with it all. The part I bolded was to illustrate naked bias. I've said what I thought were the premises of the typical absolute interpretation, and it wasn't that. If you don't assume fixed light speed, that's fine. Very few of the usual definitions apply then, so you'll have to come up with your own new ones.
This is,I believe, the most forceful objection that can be mounted against any theory that entails the existence of absolute rest. But there is a perfectly satisfactory answer,the gist of which is that, if it is true that the modified theory entails that there is,in nature, a conspiracy of silence with respect to the existence of absolute rest, this is so only because,and precisely because, the Special Theory of Relativity itself entails that there is,in nature, a conspiracy of silence with respect to a certain matter—namely,the one-way speed of light.Suppose that an experiment is possible that would enable one to measure the one-way speed of light. If the outcome of that experiment were that the one-way speed of light was the same in all directions in all inertial frames,then the modified theory would be conclusively refuted,since,as we have just seen, it entails that this will not be the case. If,on the other hand,it turned out that the oneway speed of light not only was not the same,but varied in accordance with the above relation, then it would be possible to determine the velocity of any inertial frame relative to absolute space. So,unless there is a conspiracy in nature that prevents any measurement of the one-way speed of light,the choice between the modified theory and standard formulations of the Special Theory of Relativity is experimentally decidable.Suppose,however, that there is no experimental way of measuring the one-way speed of light. Then there will be no way of determining the velocity of any inertial frame relative to absolute space,and there will be the conspiracy of silence that Zahar contends is an objection to theories that postulate absolute space. But we have just seen that a conspiracy of silence with respect to absolute rest and motion can obtain only if,and precisely because, there is a conspiracy within nature with respect to the measurement of the one-way speed of light. So any conspiracy of silence within nature that one must countenance,on the modified theory,is either identical with, or derives from, a conspiracy of silence that one must countenance according to any version of the Special Theory of Relativity
It is a simple matter of fact - call it a brute fact - that if you make a conclusion about something which you have not empirically observed, then you are assuming that conclusion.
Take Alice on her trip to Loch Ness. Standing by the lake, she sees bubbles rising to the surface and she concludes that the Loch Ness Monster is in the lake. Alice is assuming her conclusion.
these clever people - who are not my peers ...Thanks to these very clever people
we have a number of more intuitive and intelligible thought experiments which can help us draw conclusions about the competing and mutually exclusive interpretations.
the process of synchronising 2 clocks, in the given frame
in this particular set-up, is done by establishing by definition that the time from A to B1 equals the time from A to B2 (together with the time for the return trips being the same).
If we take the contention that the simultaneity of clock synchronisation events is derived and not assumed
If we establish by definition that the time from A to B1 equals the time from A to B2 (and likewise for the return jounrey)
then there are 2 things that we can "derive" from that:1) the clock synchronisation events are simultaneous, in the given frame i.e. they co-incide with the reading d/2 on the clock at the mid-point.2) the light pulses will return to the mid-point simultaneously.Here, we have derived two statements about the configuration of the physical system.
While the two statements have been derived from the same information, there is a key difference between them. That difference pertains to their empirical verifiability. As we know, statement #2 above can easily be tested and indeed it is. It represents a testable prediction of all of the various interpretations.
As we both know, as you have stated on numerous occasions, #1 above simply cannot be tested.
While the fact that it can't be tested puts it into a different class than statement #2, this different classification doesn't explain away the fact that it represents an untestable prediction.
The fact that the conclusion, that simultaneity is relative.
OK, she did assume isotropy to make her claim.
She can assume isotropy all she wants but assuming isotropy doesn't show her that her clocks are synced in her frame, it only means that she assumes they are synced in her frame.
When you clarify what you mean by "stationary system" above, we can go through the differences in the interpretations.
They actualy do make slightly different predictions, but predictions which cannot be tested.
We can see how both (or all) intepretations actually necessitate a privileged reference frame
Again, you freudianly prove my point. If they don't know that the pair of clocks are syned in any interpretaion (inluding SR) then they must be assuming that the clocks are syned - in the given frame.
If you find a single animal hair on the sofa and the evidence apparently fits the interpretation that it was left by dog and the interpretation that it was left by a cat (imagine you can't test it for whatever reason).
I'm not sure which interpretation your advocating there where absolute simultaneity and the relativity of simultaneity re not mutually exclusive.
As you progress thru your history book (trust me, it gets even more exciting than Romer) you will see that Einstein's SR overturned Newton's absolute time and space and with it, the concept of relativity of simultaneity overturned absolute simultaneity.
You seem to be basing it on the idea that the mathematics for both theories is identical and so the mathematics is compatible with both.
You might be advocating the less well known Schroedingers Cat interepretation of relativity, as outlined by Fie Lyne, which says that simultaneity is both relative and absolute and the wave function is only collapsed with the measurement of the isortropic one-way speed of light, as it pertains to Einstein's theory.
Nope, but a sneak preview of a later argument (if we get that far) is that the Haefele-Keating experiment, along with many other empirical tests of relativity (and deductions from the thought experiments) provide justification for a privileged reference frame interpretation - not one where the absolute rest frame is the privileged frame.
I can appreciate the "shut-up and calculate" approach, but inspite of this, interpretations of physical theories abound.
I just meant that if one theory passed while the other failed, the theory that passed woul be "verified" over the other.
As we discussed, we can derive a statement about the configuration of the physical system that Alice is in, which says that the reading d/c (on the clock at the midpoint) co-incides with the clock synchronisation events at B1 and B2.
You see, you've mistaken my recognition of the fact, that your point about Romer is a meaningless irrelevancy in the context of this discussion
When the fact of the matter is, I have addressed it, in the context of the discussion pertaining to the isoptropic one-way speeed of light as it pertains to Einsteinian relativity. I have addressed it by presenting peer reviewed references that pertain to the isoptropic one-way speed of light as is relevant to Einsteinian relativity, which demonstrate that it hasn't yet been measured to a satsisfactory degree
If however, you find it difficult to give up continual references to your [seeming] hero, feel free to state the point you are trying to make, clearly and coherently, and be explicit in how you believe it is relevant to the discussion of Einsteinian relativity, bcos I am saying that it isn't relevant.
You could state how you believe it is pertinent to modern day attempts to measure the isotropic one-way speed of light
Quote from: HalcWhat is relevant to this thread?I posted the paper in the OP, this thread has been spent addressing the objections that you have raised.
What is relevant to this thread?
Quote from: HalcMy defense of SR rests on its lack of being falsified. What Alice and Bob are doing is irrelevant to that unless what they actually conclude (not your strawman conclusions) is found to be in contradiction with the premises of SR.Unfortuntely, there was nothing in Kahneman's book on how, after repeatedly pointing out the error that someone is making, how to make them recognise that error and to stop making it.
I am not trying to demonstrate a contradiction in SR!!
===================Absolute Interpretation===================Quote from: HalcShall we do that? It might be instructive. Alice is in the stationary system, but it hasn't been specified if she knows that. If she doesn't know, then her clocks are synced but she has no no way to determine that. Bob once again agrees with everything and makes no contradictory conclusions.By "stationary system" here do you mean the absolute rest frame? As in, are we starting with Alice in the absolute rest frame with Bob moving relatively - even though Alice cannot determine that she is in the absolute rest frame?
It's an important distinction.
Just to be clear, the interpretation Im advocating is one that employs a round-trip speed of light principle, so it will be empirically equivalent to the other interpretations.
That's fair enough. The mathematics for all the various interpretations appears to be the same.
It is the Einsteinian interpretation that I am challenging - and the absolutist one for that matter, as I am saying the absolute reference frame can be discarded.
So, it's not that nature privileges a particular reference frame, its that we must privilege one particular reference frame as a matter of operational necessity
for us, by default, that is the reference frame of the Earth (for obvious reasons).
We also privilege the Earth reference frame by designating it our chosen reference frame for the definition of the units of measurement that we use in our experiments.
You may have misread the part I quoted, it says that the modified theory does not entail the One-Way Light Principle. The theory that pooley proposes, and which I would borrow the phrasing from, employs a round-trip light principle.
the Round-Trip Light Principle—where this is the principle, not that the round-trip speed of light is a constant relative to all inertial frames,but rather that the round-trip speed of light is a constant as measured within all inertial frames.
He also addresses the issue of the undetectability of the absolute reference frame
Poincare started with the absolute reference frame and had two inertial frames moving relative to that absolute frame, S and S'. Galilean transformations were used between the absolute reference frame and each of S and S', but the Lorentz transformation was used between S and S' themselves. In these reference frames Alice's clocks would not be synced, in her frame.
If that were true, all mathematical proofs would be rendered circular since none of them are based on any empirical observation.Alice has not made a claim of proof of anything. She has made a simple abstract statement that if she draws a line here, the rock is below it, and maybe above this other line drawn. The fact that nobody can empirically see her line doesn't alter her statement.
That she would be.The claim in the example is not like that, and thus your Ness example is an inappropriate analogy. She's made no physical claim. Never does she conclude that any of her premises are true, or that any of the conclusions are true sans contingency on the premises.In short, she never concludes that the clocks are in sync, which is arguably a physical claim (and arguably not).
I've apparently struck a nerve. Must be on to something.
What definition is now being referenced? I agree that we set it up for the times to be the same, but I am unaware of a definition being utilized this time....Again, what definition?
I can't think of any thought experiments that demonstrate a preference for one interpretation over the other. Perhaps they're not clever enough.
QuoteIf we take the contention that the simultaneity of clock synchronisation events is derived and not assumedI didn't say that. I said RoS is derived from SR premises. The above statement is not a statement of RoS.
Actually, only number 2 is a physical statement. #1 involves only a statement concerning abstract coordinate time....Because that one is a physical statement, yes. The other is not....
I can perform the in-sync test, but that test again only verifies an abstract coordinate concept. No physical (or even metaphysical) statement is made in #1, so there is nothing to verify.
It doesn't represent a prediction at all.
That conclusion is contingent on the premises, not concluded absent them. If premises, then RoS. No ∴RoS period. Your insistence on the latter is a strawman. I'm well aware of the validity of the interpretation that posits actual simultaneity, and that it is absolute. The relative interpretation makes no statement concerning actual simultaneity, only abstract coordinate simultaneity. The interpretation is very light on metaphysical additions (like preferred frames, locations, moments, aether, whatever) , which is why it is the mainstream interpretation. All those additions seem like Loch Ness monsters to me. Not asserting no monster, but it seems just silly to posit one or several.
I take this back. Reading carefully, she doesn't. She utilizes a convention to make her claim. No isotropy is assumed. The clocks are defined to be in sync in that frame by that convention, and no assumptions need be made at all. This is why her (completely abstract) claim does not conflict with interpretations that make different assumptions. No assumption with which to conflict. That's the beauty of a theory that makes no metaphysical assumptions. None of the conclusions are metaphysical ones, and all your attempts at conflict are on the metaphysical level.
Lloyd (1988: 2), a philosopher of evolutionary biology, stated that, ―Under a general hypothetico-deductive view of theories, a theory is understood as offering hypotheses from which, in combination with empirical assumptions, deductions can be made regarding empirical results.
Why look at the deflection of a particle’s trajectory in an electromagnetic field in order to measure its charge? – and doing so will demand a large number of auxiliary empirical assumptions.
The model solves for the mass evolution based on what are thought to be the dominant input boundary conditions. Some empirical assumptions are made to predict the behavior of lower order physics.
By identifying the energy that must be absorbed through deformation of the vehicle’s roof using the FMVSS 216 five inches (127 mm) of roof crush strength limit as a constraint, it was possible to calculate theoretically using some broad empirical assumptions generated from rollover crash test data, Vehicle roof strength as it relates to contained occupant injury prevention during rollover crashes
one word of caution is that the Doppler Dimming method strongly depends on empirical assumptions of the electron density and ion temperature, thus possibly leading to different results with different assumptions (Wilhelm et al. 2011).
You seem to have edited out the 'above'. If I say 'the stationary system', the term only has meaning in an absolute interpretation, so I probably meant actually stationary.
You and I have a different definition of 'prediction' then. You apparently mean different metaphysical descriptions of the system. I don't call those predictions. The relative interpretation doesn't make many such statements, only empirical predictions and abstract relations with coordinate systems such as an abstract line being above a rock.
Ah: An assertion that the relative interpretation requires a metaphysical addition despite never using it. I can see no such thing. The interpretation makes no conclusions/statements concerning this privileged frame.This is akin to asserting that a triangle cannot be discussed in a geometry class without assigning it to the actual coordinate system (as opposed to any other coordinate system, or no coordinate system).....Perhaps you can distinguish the two. I tend to use the two terms interchangably, which I would not wish to do if they mean different things.
This comment makes no logical sense. If I don't know whats in my left hand, then I must assume that I have a coin in my right. The one just doesn't follow from the other.
An animal hair is physical evidence. Alice hasn't got that and has thus made no metaphysical claim. A non-metaphysical claim does not conflict with a metaphysical claim. That claim is sort of like positing the dog, except without even finding the hair.
I'm comparing (not advocating) the SR theory with no additional metaphysical assumptions (not even fixed one-way light speed), with the absolute interpretation. Only the latter adds all these metaphysical assumptions. Since the former interpretation doesn't deny any of them, it isn't incompatible.
QuoteYou seem to be basing it on the idea that the mathematics for both theories is identical and so the mathematics is compatible with both.I've not been discussing Newton's theories. If you don't mean that one, then which two theories?
That's a thing? Never heard of it. Sounds pretty hokey.
Quote from: Halc on 08/07/2019 20:51:59You see, you've mistaken my recognition of the fact, that your point about Romer is a meaningless irrelevancy in the context of this discussionDepends what you think my point was concerning it. There were two in fact, both relevant. Neither had anything to do with measurement of the one-way speed of light.
QuoteYou could state how you believe it is pertinent to modern day attempts to measure the isotropic one-way speed of lightI would be lying if I said that. It isn't pertinent at all. You said that, not me.
Wow, that statement makes it sound like it was measured at all, just not very accurately.
The first point was brought up when the subject first came up: An illustration of a different sync convention that the one Einstein (and Lorentz) uses.
The 2nd point was my suggestion that you consider the experiment being done in a system where light speed is 3x in one direction as it is in the opposite, and what result would be measured if the experiment was done in both directions in attempt to test this. I'm not sure about that one myself. Barring that funny interpretation, perhaps just describe the experiment in standard absolute terms where light speed is constant in all directions, but the test system is moving at half light speed. I want to see if you have any idea what you're talking about.
Are you saying I'm making an error in the statement above? Or just an error in realization of your purposes here?Anyway, yes, I've had trouble with exactly that. You repeat errors that I've pointed out.
Fine. I believe you. But I'll still comment whenever I think the position is being misrepresented, for whatever purpose. If you're trying to argue that other interpretations are valid, nobody has disagreed with that. If you have a different interpretation than one of the usual ones, then I've yet to render an opinion of the validity of it on the surface.
This is the absolute interpretation, so there is one meaning to 'stationary system'. It means her position is not changing. Bob is moving. Not relatively. Moving period. That's how the absolute interpretation words things. Motion is property, not a relation under the interpretation.Feel free to tell me I'm misrepresenting the interpretation. It is waters I don't usually find myself in. Wording things in such a manner is not second nature to me.
The transformations involved three reference frames. Frame S0 is at rest in the ether, S is a Galilean frame moving with velocity v with respect to S0 , and S' is an auxiliary frame that also moves with velocity v with respect to S0 . S0 and S are connected by the Galilean transformations, whereas S and S' are connected by the transformations [symbols didn't render] . Combining these two transformations we obtain the transformations connecting S and S'.
In this paper I argue that the case of Einstein‘s special relativity vs. Hendrik Lorentz‘s ether theory can be decided in terms of empirical evidence, in spite of the predictive equivalence between the theories. In the historical and philosophical literature this case has been typically addressed focusing on non-empirical features (non-empirical virtues in special relativity and/or non-empirical flaws in the ether theory). I claim that non-empirical features are not enough to provide a fully objective and uniquely determined choice in instances of empirical equivalence. However, I argue that if we consider arguments proposed by Richard Boyd and by Larry Laudan and Jarret Leplin, a choice based on non-consequential empirical evidence favoring Einstein‘s theory can be made.
QuoteIt's an important distinction.What distinction? There seems to be only one way to use those words. You had suggested before a possible difference between the absolute frame and the preferred one. I presume those to be the same, so feel free to clarify if they're not.
QuoteJust to be clear, the interpretation Im advocating is one that employs a round-trip speed of light principle, so it will be empirically equivalent to the other interpretations.That remains to be seen. I've not seen it.
That's not true. Simpler in some ways, more complicated in others. Try to imagine implementing a speed limit sign on the side of the road using the absolute interpretation. Can be done, but it wouldn't be very helpful to the guy reading it. Such examples is why physics is far simpler with the relative interpretation.
Could be interesting.
That's a redefinition of how the term is used in physics. Perhaps you should choose another one. Why do reunited instruments need a frame? They can reunite on the fly, comparing results at some event as they pass. Events don't have frames.
That's exactly what Alice has done when she selects her abstract coordinate system. How is it going to be different than the standard interpretation then?
Quotefor us, by default, that is the reference frame of the Earth (for obvious reasons).That frame isn't inertial. In fact it is an accelerating/rotating reference frame, with a funny set of properties all its own.
Hate to be picky, but frames don't define units. They don't even define origins. OK, the rotating frame could define a unit of time period, even though we don't use it. We cut up time from a standard one rotation plus nearly 236 seconds. The meter? Somebody pulled that out of his arse. I don't think anything on Earth really suggests it.
Empirical measurements agree with that and much more. Why not take the full statement that all of EM is included in principle of relativity? That doesn't assume anything, and it includes your subset principle. Why go for the weak premise when there's a stronger empirical one?
The quote doesn't say much. It says you can't tell. Nothing in it was news to me. Sounds like "A conspiriacy to hide the invisible pink elephant is equivalent to a conspiracy to posit an invisible pink elephant, therefore there is as much reason to posit the invisible pink elephant as there is to not do so.The reasoning seems to be a refutation to some (not included, but probably involving conspiracy to hide) argument against the absolute interpretation, but none of it seems relevant to actually finding a logical flaw in any of them.
In this interpretation, I don't know what it means to be synced in a frame. Synced is an absolute thing, not a frame thing, so those words have no meaning. I can't follow this.
I don't know the base premises. You talk about starting with an absolute frame, but then use relative, not absolute terminology. Most absolute interpretations don't talk about frames at all. Alice and Bob are moving, with different velocities. That's all. This is obviously a different interpretation, but I don't know what any of the terminology means.
The rules of empiricism do not apply to mathematic bcos, as has been repeatedly stated (by both of us) mathematics is abstracts
But, just as the rules of empiricism do not govern mathematics, neither do the rules of mathematics govern empiricism.
That is why mathematically derived predictions are required to be verified/falsified by way of empirical observation. Empirical observation trumps mathematical derivation.
Theory and InterpretationForgive me if I'm using the terms imprecisely here, but I'm hoping you will understand the point that I am trying to make, as opposed to getting caught up in any imprecise usage of terms. If I understand your usage of terms correctly, the "theory" appears to represent the mathematical formalism, sans metaphysical assumptions. Essentially, the Lorentz transformation, metric, etc. Am I correct in that?
If so, then we can conclude that the relativity of simultaneity isn't derived from the mathematics.
How can we conclude this? Bcos the absolutist interpretations are mathematically equivalent but do not incorporate RoS.
We can still use the term "derive" to describe the statements that each interpretation necessitates, bcos they can be derived from the mathematics together with the mataphysical assumptions.
But - and I'm stating the obvious bcos it appears to be part of the issue - scientists (as opposed to mathematicians) are in the domain of empiricism. This is why they didn't simply accept what Einstein had derived mathematically as a given, instead they derived predictions from Einstein's interpretation (theory??) and then sought to test those empirically
And, while SR stood up to every single test, it appears to be less well understood that so too did all of the mathematically equivalent, absolutist interpretations.
In comes the thought experiment with Alice and Bob. Usually, these thought experiments are used as a means to demonstrate the empirical consequences of Einstein's interpretation....They represent real-world scenarios which is why they are employed to demonstrate the empirical consequences logically necessitated by the different interpretations....As they represent an idealised experimental set-up, they demonstrate to us the empirical consequences that are logically necessitated by the different interpretations. In this manner we can apply the rules of empiricism - not the rules of mathematics - and see what empirical derivations we can make.
This is partly the reason why the intuitive response to reading Alice and Bob is to make the assumption that the premises of SR are implied. But we're not doing that. We're assuming the premises of no interpretation.
Yes, the thought experiments are abstract but they are not abstract in the sense of being purely, mathematical abstractions.
They are abstract in the sense that talking about and describing the Hafele-Keating experiment (or any other such test of relativity) is abstract, but not in a mathematical sense. They are abstract descriptions of real-world experiments.
The power of a thought experiment is that it allows us to represent a real-world experimental set-up which cannot be carried out for practical reasons - we aren't able to accelerate spaceships up to the speeds involved.
Empirical Assumptions
See the bottom of this post for contextual examples of the term "empirical assumptions". You might use the term "metaphysical assumption", but we will see why the semantical difference is immaterial.
An empirical assumption is an assumption about how the physical world is/should/must be in order for a given interpretation of empirical evidence to be made to fit the conclusions drawn from that evidence. If the empirical assumptions aren't granted, then the conclusions, drawn by the given interpretation, don't stand-up.
As has been stated repeatedly, we can derive 2 statements about the physical configuration of Alice's system:1) the reading d/c on clock at C0 must co-incide with the clock synchronisation events at C1 and C2. 2) the light signals [must] return to the mid-point simultaneously and co-incide with the reading 2d/c on clock C0.
On the other hand, statement #1 above, which has been derived from Einstein's interpretation of the mathematics
cannot be verified empirically. It is therefore an untestable prediction; it is unfalsifiable*.
It is unobserved. Not only is it unobserved, it would appear to be unobservable.
In the domain of empiricism, something which is unobserved or unobservable constitutes an "empirical assumption".
The intepretation makes a claim about the configuration of the physical system.
1) Reading [d/c] on clock C0 = physical claim
2) Light signal making contact with C1 (synchronisation event at C1) = physical claim3) Light signal making contact with C2 (synchronisation event C2) = physical claim
4) 2 & 3 coinciding with 1 = physical claim
5) Reading [2d/c] on clock C0 = physical claim
6) Light signals returning and co-inciding with 5 = physical claim.
Her conclusion of RoS can be stated as:a) #4 above together with b) not #4 in relatively moving frames
I was emphasising the fact that those "very clever people" (your peers maybe?) derived a number of insights about the Einsteinian intepretation, which weren't expressly stated in the 1905 paper.
I agree, RoS is derived from SR premises. The one-way speed of light is assumed
OK, then we can conclude that RoS isn't an accurate representation of the physical world.
Its an abstract mathematical proposition which is compatiblle which in no way contradicts absolute simultaneity.
Quote from: HalcI can perform the in-sync test, but that test again only verifies an abstract coordinate concept. No physical (or even metaphysical) statement is made in #1, so there is nothing to verify.There might be one small matter to verify.Can you empirically verify that the reading d/c, on clock C0, coincides with the synchronisation events at C1 and C2, thereby confirming that your co-ordinate system is an accurate representation of the physical system it purports to describe;
can you verify that, in the real-world, the physical world, that the time co-ordinate (d/c) - as provided by the physical clock C0 - can reliably be ascribed to the events at C1 and C2
can you verify that both events coinicde with the same reading on clock C0, given that there is an alternative, mathematically equivalent co-ordinate system which implies that both events do not coinncide with the same reading on clock C0?
Quote from: HalcIt doesn't represent a prediction at all.Oh but it does! If I say to you that at the very moment you and I are standing in the same room, at that very moment there is a clock in the next room which reads d/c, that is a prediction.
are you saying that SR does not confict with, or make any claims/statements/etc. which contradict the absolutist interpretations?
Btw, the premises of SR assume isotropy and as you have been so eager to point out, "she is assuming the premises of SR" ergo isotropy is assumed and with it, the conclusion of RoS.
If you're arguing that she doesn't assume isoptropy
But yes, that is the point that I wanted to clarify, whether or not you were talking about absolute rest.Btw, as we have already covered, Einstein uses the term "stationary system" in his paper.
Quote from: Halc You and I have a different definition of 'prediction' then. You apparently mean different metaphysical descriptions of the system. I don't call those predictions.I mean statements about the physical configuration of the system.
You and I have a different definition of 'prediction' then. You apparently mean different metaphysical descriptions of the system. I don't call those predictions.
I talking about the reading on a physical clock being simultaneous with a physical photon making physical contact with another physical clock. But you seem to be of the opinion that this isn't a physical statement.
Again, contemplate the twin-paradox and the Hafele-Keating experiment. How do they end? They end with the twins/measuring instruments being reuinited in a single reference frame for comparison.
Reuiniting the measuring equipment like that in a single reference frame privileges that reference frame.
It doesnt mean it is an absolute reference frame, it just means that there is an automatically ascribed asymmetry where one inertial frame is "forced" to undergo acceleration while the other isn't.
The hair represents the physical evidencce of the light signal returning simultaneously, from which she cannot conclude that the clocks in her frame are synchronised.
Quote from: HalcI'm comparing (not advocating) the SR theory with no additional metaphysical assumptions (not even fixed one-way light speed), with the absolute interpretation. Only the latter adds all these metaphysical assumptions. Since the former interpretation doesn't deny any of them, it isn't incompatible.You mean you are comparing the Lorentz transformation and other mathematical artefacts with the absolute interpretation? Then you are arguing a new kind of strawman.
Quote from: HalcIf you don't mean that one, then which two theories?Etherless Lorentz-Poincare theory or the forumulation as outlined by Michael Tooley. You know absolute interpretations of relativity.
If you don't mean that one, then which two theories?
Quote from: HalcQuoteYou could state how you believe it is pertinent to modern day attempts to measure the isotropic one-way speed of lightI would be lying if I said that. It isn't pertinent at all. You said that, not me.I said precisely the opposite. I called you on your red-herring. Yet, you tried to persist with it. It's a level of intellectual dishonesty I haven't encountered before but at least when it came down to it, you have admitted its irrelevance to the topic of this discussion.
It's a separate philosophical discussion to determine in what sense one can say he actually measured the speed of light. He made measurements and got a value, did he actually measure the speed of light tho?
But not free of the same issues that all sync conventions apparently fall foul of.
You're basically asking what would happen if we actually measured the one-way speed of light
As per the Michael Tooley quote, if you could measure this then you could detect your absolute motion relative to the abssolute frame.
This leads to slightly different conclusions than SR, but not in terms of things that can actually be tested.