- #36
PeterDonis
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PeterDonis said:This is out of bounds for PF discussion. Please do not mention it again or you will receive a warning.
I have edited the post to remove the out of bounds content.
PeterDonis said:This is out of bounds for PF discussion. Please do not mention it again or you will receive a warning.
Elias1960 said:In a discussion about hidden variable theories for quantum theory, the context is not that of relativity.
Elias1960 said:you certainly have to make assumptions about the fundamental character of relativistic symmetry. They are necessarily metaphysical, which means, they cannot be supported by observation alone
Elias1960 said:Else, we have the equations for sound waves
PeterDonis said:The "context of relativity" here means the basic principle of relativity, that the laws of physics are the same in all frames. It does not mean "relativity" in the sense of the specific theory of SR.
Elias1960 said:In a discussion about hidden variable theories for quantum theory, the context is not that of relativity.
Elias1960 said:And you certainly have to make assumptions about the fundamental character of relativistic symmetry. They are necessarily metaphysical
This "modern derivation" does not present anything at all which would suggest that general assumptions about fundamental symmetries are somehow experimental. They cannot be by their very nature. Experiments give only approximate results, and so they cannot allow, even in principle, to distinguish fundamental symmetries from approximate symmetries. (Ok, except in the case when the approximate character follows already from the experimental data.)bhobba said:No they are experimental. Its not really on topic for this thread but to understand SR you really need to see a modern derivation of it:
http://www2.physics.umd.edu/~yakovenk/teaching/Lorentz.pdf
As if somebody has questioned the measurements of the speed of light.bhobba said:The constant c that appears in the equations can be, and has been, determined in many ways and all are in agreement.
Metaphysical ideas about the importance of symmetries are already quite old now, they were modern 1905 or so. And, in fact, symmetries have always impressed people, in particular, mystics. If you prefer threads going into something wrong given that you forbid certain types of counterarguments (with your "they are experimental" as an example), your choice.bhobba said:Just a note, as a moderator, explaining why, by forum rules, we do not discuss LET here, except in a historical context. The modern view of SR is very clear, and illustrative of modern physical ideas of the importance of symmetry. The forum rules are, in part, to stop threads that by their very nature would not really go anywhere.
Just clarify what I mean by infinite speed of propagation, and what the standard terminology is as far as I understand it. If the electromagnetic field had infinite speed of propagation, then the compas needle over there would move the instant there is current in the wire over here, no matter how far apart they are. So, why do you think that this, for any field, would not be in conflict with relativity and experiment? By the way, why do you put "" around tested corollaries? Are you claiming that there aren't any?Demystifier said:What "tested corollaries" do you have in mind?
They should use relativistic QFT. If you want to discuss locality you can never argue with non-relativistic approximations, because there's nothing in Galileo-Newtonian physics which guarantees locality, and already in the Theoretical Physics 1 quite in the beginning we violate it when we write down Newton's Law of gravity. There's nothing wrong with that, but as you rightly say, it's an approximation with some limited range of applicability. It's well applicable within the solar system, but there are also deviations from it known already in the 19th century (perihelion shift of Mercury).bhobba said:So those that use locality as an argument in ordinary QM strictly speaking should use QFT.
Elias1960 said:This "modern derivation" does not present anything at all which would suggest that general assumptions about fundamental symmetries are somehow experimental.
Elias1960 said:Experiments give only approximate results, and so they cannot allow, even in principle, to distinguish fundamental symmetries from approximate symmetries. (Ok, except in the case when the approximate character follows already from the experimental data.)
Elias1960 said:As if somebody has questioned the measurements of the speed of light.
Elias1960 said:Metaphysical ideas about the importance of symmetries are already quite old now, they were modern 1905 or so. And, in fact, symmetries have always impressed people, in particular, mystics. If you prefer threads going into something wrong given that you forbid certain types of counterarguments (with your "they are experimental" as an example), your choice.
Everything. It is a general statement, and general hypotheses cannot be verified by experiments. They can only be falsified.bhobba said:What about, for example, the laws of physics is the same in all inertial frames or frames moving at constant velocity to an inertial frame. What is not experimentally verifiable about that?
So why you make, then, claims about such conjectures being verifiable?bhobba said:We all know the game of science - we can never prove a conjecture by experiment, only check if the experiment supports it.
The point being? It was never a problem to derive the Lorentz symmetry from some general metaphysical hypotheses.bhobba said:The exact speed is not the issue - it's what is said in the paper:
'Knowing about the Maxwell equations and electromagnetic waves, we can identify this parameter with the speed of light.'
It is certainly not superseded by any experimental fact.bhobba said:We forbid very few things here. Yes LET is forbidden - but that's only because it is well and truly superseded so is confined to its historical context.
First, mathematics is mathematics, theorems do not need interpretations. But if a given symmetry is fundamental or approximate, and if everything is symmetric or only some part of objective reality, requires interpretation. If time translation invariance is only approximate, then I would expect that energy conservation will be only approximate too. About the metaphysical questions related to energy, I would recommend you to inform yourself in discussions about energy-momentum pseudotensors in GR.bhobba said:But regarding symmetries being metaphysical and requiring interpretation what about the modern definition of energy as the conserved quantity implied by Noethers Theorem and time invarience? Is energy just 'metaphysical'?
I answer questions where they appear. I don't want to delve into this further, but once you continue - I don't like to create the impression that I have no answers to such questions.bhobba said:But please do not post in this thread, start another thread if you want to delve into it further.
Elias1960 said:Everything. It is a general statement, and general hypotheses cannot be verified by experiments.
Elias1960 said:First, mathematics is mathematics, theorems do not need interpretations.
Facepalm. A physics forum where one is not allowed to discuss the scientific method.bhobba said:BTW discussion of Philosophy is not allowed here.
The only question which remains is if this only a particular accidental situation in the moderation team here, or is this simply the general situation in modern physics? In fact, I would tend to the second answer - a complete lack of education about methodology, a strong prejudice against discussions of interpretations in general, and questioning the spacetime interpretation of relativity being anathema seems widely distributed.bhobba said:The reason is we do not have a mentor suitably qualified in both philosophy and science/engineering to moderate it.
Elias1960 said:A physics forum where one is not allowed to discuss the scientific method.
Elias1960 said:I guess that discussing such general questions will be forbidden here too. Not?
Yes, but the discussion of the scientific method is part of discussing philosophy.PeterDonis said:He didn't say "scientific method". He said "philosophy". They're not the same thing.
There are a lot of quite precise arguments made, in particular, by Popper, which are beyond the "simply assertions of opinion". And how can one understand mainstream science without understanding at least the basic concepts of Popper's critical rationalism as well as the problems of empiricism/positivism?PeterDonis said:We generally do not allow discussions on topics that are simply assertions of opinion, since there is never any resolution to such discussions; people just continue asserting their opinions. PF's mission is to help people understand mainstream science.
Elias1960 said:but the discussion of the scientific method is part of discussing philosophy
Elias1960 said:There are a lot of quite precise arguments made, in particular, by Popper, which are beyond the "simply assertions of opinion".
Elias1960 said:how can one understand mainstream science without understanding at least the basic concepts of Popper's critical rationalism as well as the problems of empiricism/positivism?
Elias1960 said:Facepalm. A physics forum where one is not allowed to discuss the scientific method.
Elias1960 said:The only question which remains is if this only a particular accidental situation in the moderation team here, or is this simply the general situation in modern physics? In fact, I would tend to the second answer.
Hidden variables are theoretical elements that are not directly observable but are believed to influence the behavior of a system or phenomenon. They are commonly used in scientific models to explain and predict complex systems.
Hidden variables can include sub-structures, which are smaller components or elements within a larger system. These sub-structures are not directly observable, but they are thought to play a role in the behavior of the system as a whole.
In most cases, hidden variables cannot be directly detected or measured. They are inferred through mathematical models and statistical analysis of observable data. However, some advanced techniques such as quantum entanglement have been used to indirectly observe hidden variables.
The concept of hidden variables is still a topic of debate and research in the scientific community. While some theories and models rely on the existence of hidden variables, others reject their use as they cannot be directly observed or measured.
The use of hidden variables in scientific models allows researchers to better understand and predict complex systems. However, their existence and influence on a system can also complicate research and lead to different interpretations of data.