I Generalization of Lorentz ether

[Ilja]

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They are the reasons standardly given in relativity theory. Whether they are "satisfactory" depends on who you are trying to satisfy. But I'm not aware of any serious scientific challenges to them.

You think the violation of Bell's inequality is not a serious challenge?

You have to give up realism as well as causality if you want to defend the spacetime. An interpretation where we are, unfortunately, unable to measure with clocks and rulers which events happen at the same time, but this "same time" nonetheless exists, and "spacetime" fundamentally splits into space and time, can be realistic as well as causal.

In fact, I cannot imagine a more serious challenge of whatever belief - if I would have to give up realism and causality to defend this belief.

 

[PeterDonis]

You think the violation of Bell's inequality is not a serious challenge?

Not with respect to the classical theory of relativity, which is what I understood the OP to be asking about. It might be when we take quantum mechanics into account, although our current best theory of quantum mechanics, quantum field theory, still uses the underlying spacetime structure we are talking about. See below.

You have to give up realism as well as causality if you want to defend the spacetime.

I'm not sure I agree. In QFT, the requirement of causality is that field operators at spacelike separated events commute. That requirement does not imply that the Bell inequalities must be satisfied. So QFT can account for violations of the Bell inequalities while still having spacetime and causality. I don't think "realism" is a precise enough term to add anything here.

 

[Ilja]

Not with respect to the classical theory of relativity, which is what I understood the OP to be asking about.

Ok, the OP may have made his question in a classical context. But if there are serious challenges outside the classical domain, it would be misleading to hide them making explicit claims that you are not aware of any serious scientific challenges. This would be fine only if you would have added "in the classical domain".

In QFT, the requirement of causality is that field operators at spacelike separated events commute. That requirement does not imply that the Bell inequalities must be satisfied. So QFT can account for violations of the Bell inequalities while still having spacetime and causality. I don't think "realism" is a precise enough term to add anything here.

Yes. But this is a serious weaking of the notion of causality. It is essentially about correlations, not about causality. Fundamental principles of causality, like Reichenbach's principle of common cause, have to be given up. But to give it up is a serious damage to the scientific method itself. You know, this is the principle which forces scientists to search for causal explanations of observed correlations.

And the EPR principle of reality - more is not necessary from realism to prove the Bell inequalities - is precise enough. And obvious enough to understand that giving it up is a quite serious thing. What could be a meaningful meaning of realism if the EPR criterion does not hold?

 

[PeterDonis]

if there are serious challenges outside the classical domain, it would be misleading to hide them making explicit claims that you are not aware of any serious scientific challenges.

Until somebody constructs a physical theory that (a) doesn't use a 4-dimensional spacetime continuum as a fundamental construct, and (b) matches experiments, there isn't a serious scientific challenge. There might be various philosophical challenges (see below), but that's not the same thing.

Furthermore, any such model will still have to explain why a 4-dimensional spacetime continuum model works so well in the domain in which it's verified to work. Such an explanation will end up invoking the same considerations that have already been mentioned in this thread.

this is a serious weaking of the notion of causality.

What you mean is, it's a notion of causality that doesn't conform to your opinions about what a notion of causality should be. Whether or not I agree with those opinions is beside the point. Any discussion along those lines is philosophy, not physics, and is off topic here.

Similar remarks apply to your comments about the scientific method and the EPR principle of reality.

 

[Dale]

Ok, the OP may have made his question in a classical context. But if there are serious challenges outside the classical domain, it would be misleading to hide them making explicit claims that you are not aware of any serious scientific challenges. This would be fine only if you would have added "in the classical domain".

I disagree completely. Modern QFT is also compatible with special relativity and therefore not a challenge to the idea of spacetime either. The limitation "in the classical domain" does seem to specify the context of the OP, but is not required for PeterDonis' statements to be correct.

There are tentative theories in which spacetime may be an emergent phenomenon or something else, but there is no evidence supporting them at present and even if there were it would be more of an explanation of spacetime than a challenge to spacetime.

I think your characterization is wrong and the tone is rather inflammatory.

 

[Ilja]

Until somebody constructs a physical theory that (a) doesn't use a 4-dimensional spacetime continuum as a fundamental construct, and (b) matches experiments, there isn't a serious scientific challenge. There might be various philosophical challenges (see below), but that's not the same thing.

No, to construct such a theory is not problematic at all, such theories exist and are published.
Schmelzer, I.: A Condensed Matter Interpretation of SM Fermions and Gauge Fields, Found. Phys. vol. 39, 1, p. 73-107 (2009), arXiv:0908.0591
Schmelzer, I.: A generalization of the Lorentz ether to gravity with general-relativistic limit, Advances in Applied Clifford Algebras 22, 1 (2012), p. 203-242, arXiv:gr-qc/0205035

Furthermore, any such model will still have to explain why a 4-dimensional spacetime continuum model works so well in the domain in which it's verified to work. Such an explanation will end up invoking the same considerations that have already been mentioned in this thread.

No. The second paper contains a derivation of the Einstein Equivalence Principle which in no way invokes your considerations.

What you mean is, it's a notion of causality that doesn't conform to your opinions about what a notion of causality should be. Whether or not I agree with those opinions is beside the point. Any discussion along those lines is philosophy, not physics, and is off topic here.
Similar remarks apply to your comments about the scientific method and the EPR principle of reality.

Ok, once you think it is forbidden to discuss Reichenbach's common cause principle and EPR-realism and their role in science in a discussion about physics, I have to live with this.

 

[Dale]

Schmelzer, I.: A generalization of the Lorentz ether to gravity with general-relativistic limit, Advances in Applied Clifford Algebras 22, 1 (2012), p. 203-242, arXiv:gr-qc/0205035

I wonder if this theory is even still viable in light of recent GW observations of a black hole merger? Also, fundamentally since it has more free parameters than GR, it is more complicated than GR and unlikely to be more than a mathematical curiosity unless it correctly predicts experimental results that disagree with GR.

I think you should probably try to work through it and publish a bit more on it, particularly in more reputable journals. It seems a little premature to be promoting it until then.

 

[Ilja]

I wonder if this theory is even still viable in light of recent GW observations of a black hole merger?

I would not expect any serious differences. The GWs, as far as they are observable, are the same. I cannot afford for myself any complex numerical computations to check this, but the differences appear anyway only very close to the black hole horizon, and, anyway, only for \Upsilon&gt;0.

Also, fundamentally since it has more free parameters than GR, it is more complicated than GR and unlikely to be more than a mathematical curiosity unless it correctly predicts experimental results that disagree with GR.

The curiosity has no quantization problem at all. We know how to quantize a condensed matter theory. The non-renormalizability remains, of course, but is not problematic at all, because for a continuous condensed matter theory it is natural to be an effective theory only. All the other GR quantization problems simply vanish into nothing. This is, of course, nothing.

I think you should probably try to work through it and publish a bit more on it, particularly in more reputable journals. It seems a little premature to be promoting it until then.

I'm already sure that whatever I do more, it will be ignored anyway.

Seen the first paper? Which explains the SM in a quite simple way? Such a result would be the dream of string theory, but they have no hope to reach something similar. A derivation of the SM gauge group and all fermions from simple first principles and a surprisingly simple model. More reputable journals? Foundations of Physics not enough reputation? Sorry, but more reputable journals do not even peer-review papers about theories with the e-word. Once this paper has been simply ignored, I have given up the hope that any publication of any result about an ether theory will change anything. I probably have to wait until string theory is completely dead and people are really looking for something new.

The theory of gravity is already necessary to support this ether model for the SM. Because, else, it can be ignored with the excuse that it is incompatible with gravity. It isn't, as shown by this theory of gravity. By the way, the main formulas of the theory of gravity are also in the appendix of the Foundations Physics paper.

 

[PeterDonis]

to construct such a theory is not problematic at all, such theories exist and are published.

Do these theories make any testable predictions that are different from the standard theories?

 

[Ilja]

Do these theories make any testable predictions that are different from the standard theories?

The first paper explains the Standard Model of particle physics. Explanation is, essentially, a post-diction, a prediction about what we already know, from observation, but have no explanation for.

The Standard Model simply postulates a lot of fields. The theory predicts, starting from a sufficiently simple model, and sufficiently simple principles, the fermion and gauge fields of the SM. So, if it would have been proposed earlier, it would have predicted three generations of fermions, three colors of quarks and so on.

Which is already much much more than what string theory dreams of.

The theory of gravity predicts that the universe has to have trivial topology, and has to be flat (the flat universe is the only homogeneous one).

I hope you will apply similar criteria to my theories in comparison with string theory as well as LQG and other fundamental proposals (except, of course, for the criterion "it is mainstream").

 

[PeterDonis]

The first paper explains the Standard Model of particle physics.

Ok, but it doesn't make any new testable predictions, correct? For example, it doesn't predict new particles the way supersymmetric extensions of the SM do, correct? It just predicts the same observations that the SM predicts?

The theory of gravity predicts that the universe has to have trivial topology

I assume by "trivial" you mean $R^4$? Absolutely, or just on cosmological scales? I.e., does this theory also predict that there are no actual black holes, only apparent ones? ("Apparent" meaning "something that looks locally like a horizon and region inside it, but is compatible with global $R^4$ topology".) If so, that would be a (possibly) testable prediction that's different from at least some current models (but this is an area where there isn't an "established" theory, because we don't have an established theory of quantum gravity).

and has to be flat (the flat universe is the only homogeneous one).

I assume you mean spatially flat?

I hope you will apply similar criteria to my theories in comparison with string theory as well as LQG and other fundamental proposals (except, of course, for the criterion "it is mainstream").

Remember that PF is for discussion of already established science, not for trying to discover new science, which is what you are doing. We do have the Beyond the Standard Model forum, where the rules are a bit different because no theory beyond the SM can be said to be "established" at this point. We generally try to limit discussion of string theory, LQG, etc. to that forum for that very reason.

 

[Ilja]

Ok, but it doesn't make any new testable predictions, correct? For example, it doesn't predict new particles the way supersymmetric extensions of the SM do, correct? It just predicts the same observations that the SM predicts?

There are some additional scalar fields. Massive, with unknown but large masses, so some CDM candidates. There are also the gauge degrees of freedom, which can in some sense play the role of the Higgs.

I assume by "trivial" you mean $R^4$? Absolutely, or just on cosmological scales?

Absolutely.

I.e., does this theory also predict that there are no actual black holes, only apparent ones? ("Apparent" meaning "something that looks locally like a horizon and region inside it, but is compatible with global $R^4$ topology".) If so, that would be a (possibly) testable prediction that's different from at least some current models (but this is an area where there isn't an "established" theory, because we don't have an established theory of quantum gravity).

Correct. There is a critical parameter, \Upsilon, and for \Upsilon&gt;0 we have stable gravastars with a size slightly greater than horizon size. For large enough \Upsilon&gt;0 this would lead to observable differences, but \Upsilon would have to be extremely small for another difference, namely a big bounce instead of a big bang, to be compatible with what is known about the big bang.

For \Upsilon&lt;0 there would be nothing but a little more dark matter, so the modification of GR would be insignificant for anything observable. One could never reach the region inside a black hole nonetheless - this is because "proper time" is only interpreted as distorted clock time, not as real time, and the infalling observer would be simply frozen.

I assume you mean spatially flat?

Of course.

Remember that PF is for discussion of already established science, not for trying to discover new science, which is what you are doing.

I have not started a thread about this, recognizing very well that PF is open only to those parts of speculative science which are sociologically established by a lot of grants and so on, without caring about the real results.

I have only answered a false claim, which I have rejected with a reference to published papers. Here was the relevant claim:

Until somebody constructs a physical theory that (a) doesn't use a 4-dimensional spacetime continuum as a fundamental construct, and (b) matches experiments, there isn't a serious scientific challenge.

And I think once the theory is published in a peer-reviewed journal, and simply ignored instead of being questioned, the fact of the existence of such a theory is part of established science, not? So I think my response was appropriate and on-topic.

We do have the Beyond the Standard Model forum, where the rules are a bit different because no theory beyond the SM can be said to be "established" at this point. We generally try to limit discussion of string theory, LQG, etc. to that forum for that very reason.

If it would be ok to start a thread about my theories this would be fine.

As I have already said, I have already accepted that for the evaluation of the value of such theories it is irrelevant what has been really reached by the particular directions, what counts are published papers, received grants and other sociological points. This makes sense today, where the young scientist is extremely insecure and has to care most about the question where he gets the next grant after the end of the actual one, instead of caring which approach will win in the long run because it is better. The long run does not matter if the young scientist works, in this long run, as a taxi driver.

Nonetheless, even in such a situation it may be helpful to distribute some information about the existence of these results. So that, similar to Bohmian mechanics, it will not be completely forgotten, but at least one guy (for Bohmian mechanics, this was Bell) will know about it. And in some future the situation may become different, who knows.

 

[PeterDonis]

once the theory is published in a peer-reviewed journal, and simply ignored instead of being questioned, the fact of the existence of such a theory is part of established science, not?

Um, you are aware that my statement applies equally well to string theory and LQG, are you not? "Established" in this context doesn't just mean "published"--it means "verified by experiment". That means the theory has to make some prediction that other theories do not make, and that prediction has to be verified. Your theory does appear to make some predictions that other theories don't make (for example, gravastars instead of black holes); but those predictions can't be tested either way with our current observational abilities. That's why, as I said, we try to put discussions of string theory, LQG, etc. into the BTSM forum, and when those theories get mentioned in other forums, we try to be explicit that they're speculative, not confirmed, at this point.

If it would be ok to start a thread about my theories this would be fine.

Since, as you say, your work has been published in peer-reviewed journals, you could at least suggest it as an acceptable reference. The question would be, on what basis would you start a thread? Just saying "here are my theories, explain to me why they're wrong" wouldn't be sufficient--any more than a similar post based on string theory or LQG would. Even "here are some papers, does anyone see any issues with them?" wouldn't really be sufficient, because, as I said, PF is not for discovering new science.

even in such a situation it may be helpful to distribute some information about the existence of these results.

PF isn't for this either. Your papers are posted on arxiv. You can always have your own blog.

 

[PeterDonis]

The second paper contains a derivation of the Einstein Equivalence Principle which in no way invokes your considerations.

I'm not sure I understand. The theory still uses the underlying manifold $R^4$, and still defines a metric on that manifold with a (1, 3) signature. The metric is technically not "fundamental", since it's constructed from other entities, but it's there, and its existence, AFAICT, is crucial to the derivation of the EEP. This derivation doesn't explicitly mention the considerations discussed earlier in this thread, but it certainly relies on them implicitly since they are equivalent to having a metric with a (1, 3) signature.

 

[Ilja]

I'm not sure I understand. The theory still uses the underlying manifold $R^4$, and still defines a metric on that manifold with a (1, 3) signature. The metric is technically not "fundamental", since it's constructed from other entities, but it's there, and its existence, AFAICT, is crucial to the derivation of the EEP. This derivation doesn't explicitly mention the considerations discussed earlier in this thread, but it certainly relies on them implicitly since they are equivalent to having a metric with a (1, 3) signature.

What is crucial for a derivation is what one has to assume. The metric itself is not fundamental, and it is also not assumed.

In fact, the main points of the derivation do not even mention the metric. We have classical Noether conservation laws, because of translational symmetries. This gives an energy-momentum tensor. This tensor is identified with the gravitational field - which is roughly the definition of the gravitational field. All other fields are called matter fields. The Noether connection between translational symmetry and conservation law has, in the formalism, the form that the conservation laws are the equations for the preferred coordinates. Then comes the action equals reaction symmetry, and the point that by construction of the gravitational field, the equations for the preferred coordinates depend only on the gravitational field, not on matter fields. Which gives that the equations for matter fields do not depend on the preferred coordinates. Which is the EEP.

I see here no role for a metric, even less with signature (1,3). That the gravitational field is described by such a metric is the consequence of some additional assumptions. But this is in no way connected to the EEP. The EEP proof would go through even if the gravitational field - the energy-momentum tensor - would be described differently.

 

[PeterDonis]

In fact, the main points of the derivation do not even mention the metric.

Your proof that the EEP holds depends on your proof (corollary 1 in section 8) that "internal observers" can describe all their experiments and observations as if they were in a local solution of what you call "GRCF". In other words, you're depending on the fact that the solution can be described the way GR would describe it, using a metric with a (1, 3) signature.

 

[Ilja]

Um, you are aware that my statement applies equally well to string theory and LQG, are you not?

It would be nice if this would be really the case.

The question would be, on what basis would you start a thread? Just saying "here are my theories, explain to me why they're wrong" wouldn't be sufficient--any more than a similar post based on string theory or LQG would. Even "here are some papers, does anyone see any issues with them?" wouldn't really be sufficient, because, as I said, PF is not for discovering new science.

Very simple, on the same reasons people start threads in BTSM about whatever, for whatever justification. If string theory and LQG papers which have no empirical relevance at all can be posted there, why not starting a thread with much more closer relation to the SM and to GR?

I'm not sure if all the other threads of BTSM have any base at all in the forum rules. I would not wonder if not - a quite common mechanism to have rigorous rules which nobody fulfills, but if any outsider comes and violates them too, he will be punished, while the established mainstream guys go unpunished.

So I would hope (recognizing that this hope is quite naive, or, more accurate, rhetorical) that you can explain why the BTSM forum is not simply empty, and this justification would give, I think, also a justification for me to present my theory there.

Your proof that the EEP holds depends on your proof (corollary 1 in section 8) that "internal observers" can describe all their experiments and observations as if they were in a local solution of what you call "GRCF". In other words, you're depending on the fact that the solution can be described the way GR would describe it, using a metric with a (1, 3) signature.

So, ok, this particular proof relies on this. What is behind, as discussed in app. D., does not have to rely on this.

 

[Dale]

I would not expect any serious differences. The GWs, as far as they are observable, are the same. I cannot afford for myself any complex numerical computations to check this, but the differences appear anyway only very close to the black hole horizon, and, anyway, only for Υ>0Υ>0\Upsilon>0.

If the observable results are the same then the theory with fewer free parameters is scientifically preferable. But since the computation hasn't been published it is still a bit speculative to make that claim on PF.

More reputable journals? Foundations of Physics not enough reputation?

Their most recent impact factor is 1.03. At least it is not less than 1, but yes there is substantial room for improvement.

Sorry, but more reputable journals do not even peer-review papers about theories with the e-word.

So then why did you put that word in there? That seems like a really bad choice on your part.

You believe that you have an absolutely revolutionary theory that is rejected, not based on any flaws of the theory, but on a simple word choice. So why didn't you choose a different word and reap the professional rewards of your theory?

If your theory is as truly revolutionary as you believe then someone will take it and present it without that word, and then this paper will just serve as a citation in the new paper.

 

[PeterDonis]

on the same reasons people start threads in BTSM about whatever, for whatever justification.

People start threads in BTSM (or threads that get moved there) because they have questions about string theory or LQG or some other theory that goes beyond the current Standard Model (which in this context includes GR). If someone saw your paper on arxiv or in a journal and had a question about it, that forum is where the post would properly go.

People aren't supposed to start threads in BTSM, or anywhere else, just to say "I just posted this paper on arxiv, please look at it". If you find threads of that sort, you are welcome to report them so the moderators can deal with them.

I'm not sure if all the other threads of BTSM have any base at all in the forum rules.

Again, if you see a thread in BTSM, or anywhere, that you think violates the rules, the proper response is to report it so the moderators can take appropriate action.

What is behind, as discussed in app. D., does not have to rely on this.

I'll take a look at Appendix D.

 

[PeterDonis]

if it would have been proposed earlier, it would have predicted three generations of fermions

I don't see a prediction of three generations of fermions (e.g., electron, muon, tauon, and their corresponding neutrinos and quarks) in the paper. I see a derivation of the gauge group SU(3) x SU(2) x U(1), but the SM contains three copies of this group (at least for the fermions), one for each generation, not just one. Of course you could construct a model with three copies of your underlying lattice, but why must it be three?

 

[Ilja]

I don't see a prediction of three generations of fermions (e.g., electron, muon, tauon, and their corresponding neutrinos and quarks) in the paper. I see a derivation of the gauge group SU(3) x SU(2) x U(1), but the SM contains three copies of this group (at least for the fermions), one for each generation, not just one. Of course you could construct a model with three copies of your underlying lattice, but why must it be three?

No, the fermions of the theory are described by Aff(3) \times \mathbb{C} \times \Lambda(\mathbb{R}^3) which contains already three generations. \mathbb{C} \times \Lambda(\mathbb{R}^3) are eight complex fields, an electroweak doublet, and an affine matrix is 3 x (1+3), so all this corresponds to three generations times (one lepton plus three quark) doublets.

People start threads in BTSM (or threads that get moved there) because they have questions about string theory or LQG or some other theory that goes beyond the current Standard Model (which in this context includes GR). If someone saw your paper on arxiv or in a journal and had a question about it, that forum is where the post would properly go.

So, as I have guessed, all speculations are equal, but some are more equal. Namely those supported by the scientific mainstream, because only those have a chance to raise questions by young physicists who may hope for grants in such a direction.

But I see, the rules are even more open for their clear preference for established speculations. To quote:

All threads in this forum are intended for discussion of the scientific content of well-researched models of physics beyond the Standard Model that have been published in peer-reviewed journals.
This forum may not be used to propose new ideas or personal theories. All threads of this nature that are started in this forum will be removed by Mentors.

In other words, established speculative theories (named "well-researched") are welcome, new speculative theories are forbidden, even if the already published results of the new theories are much better than what the established theories have reached during their whole lifetime.

So, your forum is clearly and obviously, by the rules, designed to favor established speculative theories against new competitors. And, of course, it makes no sense to propose a modification of the rules to make them fair. They have not been designed to be fair, but designed to favor the establishment. Such is life, in politics as well as in science. Every lobby in every parliament of the world manages to design laws which favor themselves and harm competitors, so there is no reason to expect that this may be different in science.

As a new competitor I depend on loopholes in such regulations - in this case, I have used the loophole that I'm allowed to answer false claims about the nonexistence of some theories with a reference to a publication of such theories.

If the observable results are the same then the theory with fewer free parameters is scientifically preferable. But since the computation hasn't been published it is still a bit speculative to make that claim on PF.

The equations have the Einstein equations of GR as the limit \Xi,\Upsilon \to 0, the additional terms do not depend on derivatives of the metric and become otherwise large only where the preferred coordinates become singular. For \Xi&gt;0 ,\Upsilon &lt; 0 the additional degrees of freedom behave like simple massless dark matter, thus, will not cause anything problematic. So all what one has to expect from computations given the GR prediction is viable are upper bounds for the \Upsilon&gt; 0 case.

Explain your point about preferability to all the string theorists and supersymmetry and GUT lovers.

So then why did you put that word in there? That seems like a really bad choice on your part.

I thought this is science, and not a domain where political correctness matters.

You believe that you have an absolutely revolutionary theory that is rejected, not based on any flaws of the theory, but on a simple word choice. So why didn't you choose a different word and reap the professional rewards of your theory?

Sorry, no. It was not rejected, but, finally, accepted by Foundations of Physics. And I know already that even a PRD publication would not change the situation at all. A research direction which can offer absolutely not a single grant has no chance, published or not.

If your theory is as truly revolutionary as you believe then someone will take it and present it without that word, and then this paper will just serve as a citation in the new paper.

No. The preferred frame is anathema even if I do not use the e-word. To work in this domain would be, without a permanent position in the background, scientific suicide, because there are no interested journals, no conferences, no positions, no grants, nothing. If a young scientist would find my theory interesting and show some interest working in this direction, I would have to warn him.

I have had the funny experience of writing a rejection to a published paper, where even the author, heavily criticized in the paper, has recommended publication, but it was nonetheless rejected. Too much ether.

 

[Dale]

The equations have the Einstein equations of GR as the limit Ξ,Υ→0Ξ,Υ→0\Xi,\Upsilon \to 0, the additional terms do not depend on derivatives of the metric and become otherwise large only where the preferred coordinates become singular. For Ξ>0,Υ<0Ξ>0,Υ<0\Xi>0 ,\Upsilon < 0 the additional degrees of freedom behave like simple massless dark matter, thus, will not cause anything problematic. So all what one has to expect from computations given the GR prediction is viable are upper bounds for the Υ>0Υ>0\Upsilon> 0 case.

What a new theory needs is an experiment that predicts something measurably different from existing theories. In this case you need an experiment which is highly sensitive to your parameters. Then, for the theory to be useful, the experiment must be close enough to 0 to agree with other experiments, but far enough from 0 so that 0 is definitively excluded.

Explain your point about preferability to all the string theorists and supersymmetry and GUT lovers.

I agree with you here, which is why I stay out of the BTSM forum altogether.

I thought this is science, and not a domain where political correctness matters.

Science is done by scientists, and scientists are humans, so politics does matter some. The importance of politics is less than in most other fields of human endeavor because there is an objective criterion for success: experiment.

However, your theory has not passed that objective criterion, so it is more subject to politics than it would be otherwise. You find it elegant and appealing for philosophical reasons, others do not. And by labeling it poorly you have essentially ensured that it would garner minimal political support at a time when it has no experimental support.

It was not rejected, but, finally, accepted by Foundations of Physics

So then you agree that it deserves to be there? That it is an idea whose impact merits publication in a journal with an impact factor of ~1.

I have published many papers in a variety of journals. The papers that I have published in lower impact journals I recognize as being low impact papers. Often I suspected, in advance, that it would get rejected from the high impact journals.

I find that usually papers are published in the journals where they deserve to be published.

A research direction which can offer absolutely not a single grant has no chance, published or not.
No. The preferred frame is anathema even if I do not use the e-word.

Nonsense. There are many Lorentz violating theories out and under current consideration including funding and sophisticated experiments. The recently developed SME even provides a recognized test theory for such experiments.

If your assertion were correct then none of these other people or experiments would have received funding. A preferred frame is not a death sentence for a theory and it is simply against the facts to claim that the scientific establishment automatically rejects such theories without consideration.

 

[PeterDonis]

the fermions of the theory are described by $Aff(3) \times \mathbb{C} \times \Lambda(\mathbb{R}^3)$ which contains already three generations. $\mathbb{C} \times \Lambda(\mathbb{R}^3)$ are eight complex fields, an electroweak doublet, and an affine matrix is 3 x (1+3), so all this corresponds to three generations times (one lepton plus three quark) doublets.

Ah, ok, got it.

 

[Ilja]

What a new theory needs is an experiment that predicts something measurably different from existing theories. In this case you need an experiment which is highly sensitive to your parameters. Then, for the theory to be useful, the experiment must be close enough to 0 to agree with other experiments, but far enough from 0 so that 0 is definitively excluded.

So that means that we actually do not need any new theories? GR + SM are actually quite fine, except for the CDM part, which is rather unspecific, so that almost every minor modification of the SM can find some candidates.

Science is done by scientists, and scientists are humans, so politics does matter some. The importance of politics is less than in most other fields of human endeavor because there is an objective criterion for success: experiment.
However, your theory has not passed that objective criterion, so it is more subject to politics than it would be otherwise. You find it elegant and appealing for philosophical reasons, others do not. And by labeling it poorly you have essentially ensured that it would garner minimal political support at a time when it has no experimental support.

I think the explanation of the SM is a sufficient replacement for experiment, in a situation where we have no need for new theories because of problems with experiments and observation.

The theoretical problems (unification, quantization of gravity) should also count at least a little bit.

So then you agree that it deserves to be there? That it is an idea whose impact merits publication in a journal with an impact factor of ~1.

I have never thought about publication in such terms. Actually I do not have to care about impact factors at all. Anyway I do not even want a job in the mainstream where the number of citations of my papers would matter. I have accepted the challenge to publish my theories in some sufficiently good peer-reviewed journal, despite the quite extreme prejudice against the ether.

Nonsense. There are many Lorentz violating theories out and under current consideration including funding and sophisticated experiments. The recently developed SME even provides a recognized test theory for such experiments.
If your assertion were correct then none of these other people or experiments would have received funding.

Sorry, but this is about something completely different. Of course, even if everybody believes that GR is fundamentally true, experimental tests will be done simply to improve the accuracy of the tests. The experimenters are anyway not suspect of anathema if they do tests which can support the mainstream predictions. And, of course, the evaluation of such tests also needs some toy theories to see how much they will be restricted by the tests.

A preferred frame is not a death sentence for a theory and it is simply against the facts to claim that the scientific establishment automatically rejects such theories without consideration.

Not completely without consideration - in this case I could not have published them. But the papers are rejected based on minor objections, in one example the reviewer thought that the paper will be not interesting for the readers. I can compare, I have published also some papers about QM foundations, in favor of dBB theory, thus, also not exactly mainstream, but in comparison far more close. It was much much easier, and I have nothing to object about my peer review experiences for these papers.

 

[PeterDonis]

even if everybody believes that GR is fundamentally true

Does "everybody" believe that? As I understand it, the mainstream position is that GR is a low-energy classical effective field theory, and the underlying fundamental theory is some version of quantum gravity.

 

[Dale]

I think the explanation of the SM is a sufficient replacement for experiment,

There is no "replacement for experiment" in science.

Sorry, but this is about something completely different.

No, it is a direct rebuttal to your claim. You claimed that it was impossible to get funding if your research involved a preferred frame, even if you don't use the word ether. And yet there is a body of funded research that tests such theories. They use words like Lorentz violating or CPT violating rather than ether, and are able to secure funding.

The experimenters are anyway not suspect of anathema if they do tests which can support the mainstream predictions.

If a test is a valid scientific test then it must be able to either support or contradict the theory, depending on the outcome of the experiment. So of course the tests "can support the mainstream predictions". They also could contradict the mainstream predictions. That is the whole point of running the test.

But the papers are rejected based on minor objections, in one example the reviewer thought that the paper will be not interesting for the readers

That is, in fact, a major objection. I always give my judgement of the level of interest for the readership of the journal. It is important feedback for both the editors and the author.

Not completely without consideration - in this case I could not have published them.

So you believe that you are smart enough to single-handedly revolutionize all of modern physics, but not smart enough to figure out a way to describe it without using the word "ether"?

 

[peety]

Is there a good definition of 'preferred frame'? Wikipedia refers to a frame where the laws are 'different/simpler' as if that isn't a problematic distinction. In Ptolemaic times when the Earth provided the preferred frame descriptions of orbits were not just over-complex but fundamentally flawed as an explanation of planetary motion. In the context of SR and GR what would the discovery of a preferred frame imply?

 

[Ibix]

I'm not sure there's a totally clear definition because we've never found such a frame. But here's an example of what I understand by the term. The typical misunderstanding of time dilation is that the faster you go the slower time runs, and the slower you go the faster time runs. If that were really the way the world worked then it would imply one state of motion in which time ran at its maximum rate - all observers in motion with respect to this frame would see its clocks ticking faster than theirs. That would be an example of a detectable "absolute rest frame". The laws of physics would pick it out as special.

The lack of such a frame is a central concept in relativity.

 

[Dale]

Is there a good definition of 'preferred frame'? Wikipedia refers to a frame where the laws are 'different/simpler' as if that isn't a problematic distinction.

Hmm, that is a question I had not considered. I don't know if there is a standard definition, but I would probably write it as something like a frame where some Lorentz violating term goes to 0.

 

[PeterDonis]

I don't know if there is a standard definition

In the PPN formalism, "preferred frame" effects are those involving the $\alpha_1$, $\alpha_2$, and $\alpha_3$ coefficients, as described here:

http://relativity.livingreviews.org/Articles/lrr-2014-4/articlese3.html

 

[Dale]

Thanks @PeterDonis those living reviews are always good.

@Ilja the best way to compare your theory to experiment would be to calculate the PPN parameters and the SME parameters for your theory. Then you could at least put constraints on your parameters.

 

[Ilja]

There is no "replacement for experiment" in science.

That means, all the "beyond the standard model" physics is simply nonsense?

By the way, once my model gives the standard model of particle physics, instead of two or four generations and millions of other field theories one could invent, it has a much better correspondence to observation than, say, string theory, which predicts no particular property of the standard model.

No, it is a direct rebuttal to your claim. You claimed that it was impossible to get funding if your research involved a preferred frame, even if you don't use the word ether. And yet there is a body of funded research that tests such theories. They use words like Lorentz violating or CPT violating rather than ether, and are able to secure funding.

Whatever, I'm not a politician, who knows how to hide the true intentions to get money. I do not even want to learn how to do this. I'm happy enough that I'm able to secure my own survival myself, thus, do not have to care at all about getting a science job, thus, can research what I find promising.

So, let's clarify, I was unable to get any funding at the times in the past when I have tried, and given up. I cannot offer any grants myself, and I would have to warn everybody who wants to work in ether theory, in particular, developing my own theories, that this is extremely dangerous for him if he depends on getting some grant in some future.

If you think reasonable ether theoreticians would not have problems to find funding, fine. Yes, I have recognized that Jacobson continues to work and publish about his "Einstein aether". This may be reason to hope that the prejudice against the ether looses its strength with time. Actually this is not more than a little light at the end of the tunnel.

About no interest for the readers:

That is, in fact, a major objection. I always give my judgement of the level of interest for the readership of the journal. It is important feedback for both the editors and the author.

But if I care about the interest of the readers, what would be a better journal than Foundations of Physics? An interest in the foundations is something quite different from an interest in a high impact factor, which matters for mainstream research.

So you believe that you are smart enough to single-handedly revolutionize all of modern physics, but not smart enough to figure out a way to describe it without using the word "ether"?

No, not amoral enough to hide what is behind the theories, namely a revival of some quite old ideas about the ether. I have no problem to use equivalent descriptions - like "condensed matter interpretation" instead of "ether interpretation", but only as far as this does not damage the scientific content itself.

Then, of course, not to be stupid is necessary to start a scientific revolution. But it was even more important that I was not afraid of violating mainstream beliefs. So I was essentially alone in the whole field of research - making modern science compatible with the old ether - and without any competitors it was possible for me to collect all the things lying around there for free.

These two things are, imho, connected with each other. You need some own moral base to be able to work over many years in such an alternative direction, without any moral support from outside. So, if I would have been ready to distort the scientific content of my work to get published, I would have been unable to work many years on ether theory without any reasonable hope to get published.

 

[Ilja]

Is there a good definition of 'preferred frame'?

I doubt, but, fortunately, we don't really need one.

Because if the theory has a preferred frame, this is usually easy to see.

@Ilja the best way to compare your theory to experiment would be to calculate the PPN parameters and the SME parameters for your theory. Then you could at least put constraints on your parameters.

If there would be a large enough group of ether theoreticians, it would make sense for one of them to do this. But I'm alone, and have to care about my time. From this point of view, it is not promising enough. The additional parameters are essentially cosmological parameters, and I simply doubt that solar system type observations will have the ability to restrict them more than cosmology.

I'm actually working on the questions related with Hawking radiation and the trans-Planckian problem. The point will be criticism of the mainstream justification of Hawking radiation. The ether will be involved, but only as an example of a trans-Planckian regularization where we have no Hawking radiation.

This will not give anything in terms of real experiments, I know. But somehow there are already 28 papers of arxiv this year alone which mention Hawking radiation in title or abstract, thus, the mainstream does not care about this too.

 

[PeterDonis]

That means, all the "beyond the standard model" physics is simply nonsense?

No, it means it's speculative. Just as the Standard Model itself was speculative until experiments confirmed its predictions.

Work on speculative theories is part of science; however, past history shows that, without experimental input, it's very hard to make progress.

 

[martinbn]

I haven't really looked at the paper so I might be wrong. But it seems to me that you introduce two extra parameters (compare to GR) and the theory is formulated in a specific frame. This already seems unappealing. More free parameters and you have to work in the chosen frame or do the work and find the equations in a different frame. In other words more difficult to work with and more freedom to adjust. Can you show any specific computation for example the bending of light or Mercury's perihelion or anything else that leads to numbers that can be observed or measured at least in principle?

 

[Dale]

, I'm not a politician, who knows how to hide the true intentions to get money. I do not even want to learn how to do this

Then this is your choice. You have decided that obtaining the good opinion of others is beneath you. You cannot do that and then blame others for their low opinion of your work. Own your choice.

No, not amoral enough to hide what is behind the theories, namely a revival of some quite old ideas about the ether

Really? You think that your use of the word "ether" is some sort of a moral imperative. That is just plain silly. What kind of moral system requires you to use a word with negative connotations?

if I would have been ready to distort the scientific content of my work

You seem to be assuming that the use of the word "ether" is scientific content. It is not. Is there scientific content in the use of the symbol $\alpha$ vs the symbol $\beta$. Is there some sort of amoral deception or scientific distortion involved when people coined the terms "quark" or "flavor" or "beauty". Of course not.

All your talk about "amoral" and "distortion" is completely irrelevant. Your word choice is nothing more than a word choice.

 

[strangerep]

@Ilja: you claim (iiuc) to have the SM with 3 generations, but I when I searched your paper (0908.0591) for mention of the CKM matrix I found none. Do you derive it somewhere else?

Also, I did not find any discussion about masslessness of neutrinos. (?)
Or, if not massless, a derivation of the PMNS matrix?

 

[Ilja]

The aim of developing this ether theory was not at all to obtain some modification of the equation to modify some solutions. It was the problem of quantization. I have started with a simple thought experiment of quantum gravity, the gravity variant of the double slit experiment where a test particle possible measures the position. If the interaction was strong enough, then the position of the test particle will be different for different paths of the particle - and the superposition is destroyed by the measurement. Else not.

Now do this with gravity. Then you have to compare the positions of the test particle. For the two cases, that means, for two different gravitational fields. And now remember GR, diffeomorphism invariance, and the hole argument. And you will see that there is no such thing in GR as "the same position" for different metrics.

But the experiment will be the same, it will have a result. Or the test particle is at the same place, then the interaction was not strong enough and the position was not measured, or it was measured, and the superposition destroyed. So, quantum theory gives an observable which does not exist in classical theory.

So, an additional equation, which allows to define the notion "the same position" for different solutions of GR is simply necessary to compute a prediction for this thought experiment. There was a nice candidate for this - the harmonic condition. And, of course, one wants to have a Lagrange formalism for the resulting theory, that's all. It is the simplest solution for a problem which GR cannot solve but quantum gravity has to solve, to be able to compute the results of this simple thought experiment.

The parameter choice \Upsilon&gt;0 leads to nice in principle observable differences, namely stable gravastars and a big bounce instead of a big bang, thus, getting rid of the two most important singularities of GR. And of course this would be visible if the values of \Upsilon would be large enough. Then, the spatially flat universe is the only homogeneous one, thus, clearly preferred for symmetry reasons - a curved one would have to have a center. So, the "in principle observable" is not a problem at all.

No, it means it's speculative. Just as the Standard Model itself was speculative until experiments confirmed its predictions. Work on speculative theories is part of science; however, past history shows that, without experimental input, it's very hard to make progress.

Fine. But I disagree about the role of experiments in the progress. Remember on the greatest success stories of physics at all - atomic theory. How long was it "speculative", in the sense that there was no experimental proof of the existence of atoms? Quite long. Was there no progress in atomic theory over all this time? No, there was a lot of progress. But this progress was mainly explanatory. The things which were already well-known have been interpreted in terms of atomic theory. Instead of simply describing them in terms of unspecified "fields".

If we take the example of atomic theory as a pattern, we should expect that new theories have to start with interpretation and explanation of what has been already reached.

@Ilja: you claim (iiuc) to have the SM with 3 generations, but I when I searched your paper (0908.0591) for mention of the CKM matrix I found none. Do you derive it somewhere else?

No, the masses themselve are not derived.

Also, I did not find any discussion about masslessness of neutrinos. (?)
Or, if not massless, a derivation of the PMNS matrix?

There are no reasons to expect they are massless. What the model predicts is that there are right-handed neutrinos, and that they have to be inert. (This also with the additional possibility of exchanging left with right.)

What is predicted are the fermions, the gauge fields, and the charges.

In http://arxiv.org/abs/0912.3892 I give some qualitative considerations which show that the masses of the neutrinos have to be much smaller than those of the other fermions. And, given that the leptons are more closely associated with the neutrinos, one can for similar reasons expect that their masses are lower than quark masses.

The other qualitative prediction is that the massless part - that with exact gauge symmetry on the fundamental level - is U(3).

I suspect one can make some prediction about the smallness of the CP-violating terms. I would guess these terms will be created only by distortions of the ether, thus, may be even different in different regions and times.

In general I would not expect that the ether model will allow to predict all the details from simple first principles and a few qualitative properties of the model, there will be also some quantative material properties of the ether which will influence the masses.

 

[Ilja]

Then this is your choice. You have decided that obtaining the good opinion of others is beneath you. You cannot do that and then blame others for their low opinion of your work. Own your choice.

? I have decided that to use methods to cheat are beneath me. This changes absolutely nothing about I expect from others. If they would behave like what I would expect from scientists, they would look at the scientific facts, compare what different approaches have reached. I would have no problem with a low opinion if it would be based on some objective arguments. Say, that vacuum Nr. 28450433854592423095843905824905 from string theory gives a description much closer to the SM than my model. What I reject is ignorance as an argument ("your theory is ignored, thus, worth nothing") and the application of criteria which, equally applied to others, would have killed all the "behind the SM" theories together.

Really? You think that your use of the word "ether" is some sort of a moral imperative. That is just plain silly. What kind of moral system requires you to use a word with negative connotations?

The issue is not the word, but the connections between the two scientific theories. My theory of gravity generalizes a theory known as the Lorentz ether in the same way as general relativity generalizes special relativity. There have been some scientific arguments against ether theories, and these are, of course, arguments which my generalization of the Lorentz ether has to be able to answer.

"Answering" them by renaming the theory and distorting its content in such a way that nobody would try to apply these old arguments simply because nobody would see that, in principle, there is a strong enough similarity so that one can try to apply to the new theory too, would be cheating.

You seem to be assuming that the use of the word "ether" is scientific content. It is not.

No. I assume that the non-gravity limit of my theory of gravity is a theory already known and named "Lorentz ether" is scientific content. And a consequence of this fact is that one can try to apply known arguments against the Lorentz ether also against my theory. Some of them fail for trivial reasons (the Lorentz ether was incompressible, violated the action equals reaction principle by acting but not showing any reaction) because they are no longer applicable to the generalization. But all of them? Some of the positivistic "I cannot see it, thus, it does not exist"-type arguments remain unchanged.

 

[PeterDonis]

How long was it "speculative", in the sense that there was no experimental proof of the existence of atoms? Quite long.

Yes, more than two thousand years. But for practically all of that time, it wasn't a "theory" so much as an idea. Not only did the idea make no testable predictions, it didn't even have any structure built up around it. It was just the statement "matter is made of atoms", and nothing more.

Was there no progress in atomic theory over all this time? No, there was a lot of progress. But this progress was mainly explanatory.

Really? What progress are you talking about?

But this progress was mainly explanatory. The things which were already well-known have been interpreted in terms of atomic theory.

Really? What well-known phenomena were interpreted in terms of atomic theory, before the 1800s, when people finally started to figure out testable predictions from the hypothesis that matter was made of atoms, and then started testing them?

 

[Dale]

I have decided that to use methods to cheat are beneath me.

Nonsense. There is no rule which says you need to use the word ether. You use it because you like the philosophy and want to promote it, not because of some non existent rule that you are honorably obeying.

You have simply chosen to promote the word ether even to the detriment of promoting your theory. That is hardly some moral choice, just a marketing choice.

If they would behave like what I would expect from scientists, they would look at the scientific facts, compare what different approaches have reached.

But there are no scientific facts supporting your idea, and you have even decided that is "not promising enough" to even try to obtain scientific facts supporting your theory.

"Answering" them by renaming the theory and distorting its content in such a way that nobody would try to apply these old arguments simply because nobody would see that, in principle, there is a strong enough similarity so that one can try to apply to the new theory too, would be cheating.

Nonsense. Failure to cite your references would be cheating. But having cited your references there is no rule on your naming convention.

Some of the positivistic "I cannot see it, thus, it does not exist"-type arguments remain unchanged.

Which is probably the real reason that you are reluctant to pursue the experimental aspect as well as the real reason that other scientists are uninterested. If it cannot be detected then it is only philosophy, and an old philosophy that has already been rejected.

 

[Ilja]

What well-known phenomena were interpreted in terms of atomic theory, before the 1800s, when people finally started to figure out testable predictions from the hypothesis that matter was made of atoms, and then started testing them?

Let's start with 1738 when Bernoulli published his hydrodynamics, which laid the basis for the kinetic theory of gases. Then, of course, you can count Daltons law of multiple proportions, with its explanation by atomic theory, already a proof of atomic theory. But, sorry, in this case my ether model of the SM would have to count as a proof of ether theory too. And many scientists, like Mach, have rejected atomic theory much later. So, it seems more reasonable to count 1905 as the date when atomic theory was finally supported by experiment.

So we have much more than a century of development of atomic theory, read about its progress in https://en.wikipedia.org/wiki/Kinetic_theory_of_gases#History

 

[PeterDonis]

Let's start with 1738 when Bernoulli published his hydrodynamics, which laid the basis for the kinetic theory of gases.

As I understand it, nobody knew it was the basis for the kinetic theory of gases until the mid 1800s, at least; Bernoulli treated fluids as continuous substances, not as made of atoms.

Then, of course, you can count Daltons law of multiple proportions, with its explanation by atomic theory

Yes, published in the 1800s (1803, IIRC).

already a proof of atomic theory

Not according to almost every physicist of the time; it wasn't until the early 1900s that most physicists accepted atomic theory as proved, and if one had to pick a particular experiment that tipped the balance, it would probably be Perrin's experiments on Brownian motion, which confirmed the explanation of Brownian motion by Einstein using atomic theory in one of his "miracle year" 1905 papers. As you appear to agree.

in this case my ether model of the SM would have to count as a proof of ether theory too.

No, because, as you appear to agree, atomic theory was not "proved" until experiments were done confirming an explanation of something that could not be explained by the theory of matter as a continuous substance (Brownian motion). Your theory is not in that position; you claim to explain something that the Standard Model doesn't, but your theory is not the only theory that claims to explain that, and we have no experiments that distinguish between the various theories that go beyond the Standard Model.

we have much more than a century of development of atomic theory

Yes; I already said atomic theory started development in the 1800s.

 

[Ilja]

Nonsense. There is no rule which says you need to use the word ether.

Ok, I could have named a theory which generalizes the Lorentz ether, has a global Euclidean space and absolute time, filled with some condensed matter, those speed of sound is identified with the speed of light, which follows with the continuity and Euler equations classical condensed matter theory equations, and distorts rulers as well as clocks with formulas generalizing those of the Lorentz ether, googledigoog theory instead of ether theory. What would have been the point of this decision?

You use it because you like the philosophy and want to promote it, not because of some non existent rule that you are honorably obeying.

This is already poor polemics. Note also that even if it would be correct, so what? The answer is clear - it is one of the standard accusations against the ether cranks that they like some classical philosophy and that's why reject modern science.

In fact, my motivation was quite different. The original aim was solving an important problem of modern physics, namely the quantization of gravity. To quantize gravity, I need the key properties of the Lorentz ether. The simple point is that we already know how to quantize condensed matter theories. So, if we have an interpretation of gravity in terms of a completely classical condensed matter theory, including all the things we use if we quantize classical condensed matter theories, we have a way how to quantize gravity.

But there are no scientific facts supporting your idea, and you have even decided that is "not promising enough" to even try to obtain scientific facts supporting your theory.

Cheap polemics. Quantization of gravity is, it seems, not a problem at all, and explaning the quite complex structure of the SM in a simple way not a scientific problem too. And the unification of the SM with gravity is also not a problem.

Which is probably the real reason that you are reluctant to pursue the experimental aspect as well as the real reason that other scientists are uninterested. If it cannot be detected then it is only philosophy, and an old philosophy that has already been rejected.

Feel free to ignore all the problems of modern science beyond the SM as "only philosophy".

But if you think that some "old philosophy" has been rejected, it would be nice to see more than empty claims.

The positivistic arguments Einstein has used for SR he has rejected himself, in his famous conversation with Heisenberg where he has said that it is the theory which decides what is observable. And positivism, which was the leading philosophy of science in the critical time of rejection of ether philosophy, has been rejected as a philosophy of science by Popper 1935.

 

[Ilja]

Fine, almost agreement. Even if we put the origin of kinetic theory and thermodynamics in the 1850s, so what, there is a lot of time of theoretical development of atomic theory and increasing certainty that it is the correct explanation up to the time when there was agreement about experimental support.

... you claim to explain something that the Standard Model doesn't, but your theory is not the only theory that claims to explain that, and we have no experiments that distinguish between the various theories that go beyond the Standard Model.

Oh. Which other theory claims to explain as much of the standard model as my theory?

String theory is the theory where our universe is exceptional because it is the only universe which cannot be explained by it. Ok, that's a joke, but the fact remains that string theory tells us, up to now, nothing at all about the particle content of the SM. LQG does not even have this aim, afaiu. GUTs and supersymmetry postulate much larger groups, which, for unknown reasons, are then effectively reduced to the SM subgroup. Why this subgroup instead of another one remains unclear, as well as what would be the advantage of the larger group.

 

[PeterDonis]

Which other theory claims to explain as much of the standard model as my theory?

The various standard model extensions based on supersymmetry, etc. You discount these, but your reasons are similar to the reasons why others discount your theory: personal opinions about what a theory that "explains" the SM should look like. And unless and until some experiment can decide between them, we won't be able to progress any further than that.

 

[Ilja]

The various standard model extensions based on supersymmetry, etc. You discount these, but your reasons are similar to the reasons why others discount your theory: personal opinions about what a theory that "explains" the SM should look like. And unless and until some experiment can decide between them, we won't be able to progress any further than that.

I disagree. Explanatory power is essentially the same as predictive power - with the difference that what is "predicted" was already known before. So, postdiction instead of prediction, which, common sense tells us, is clearly weaker. But, nonetheless, you can compare different theories which postdict/explain the SM by their predictive power in the usual way. So, there is more to this comparison that personal opinion only. The usual way to compare the predictive power of theory - Popper's criterion of empirical content - works as usual.

So, what could falsify supersymmetry? How many QFTs are there which do not have any supersymmetric extension, so that observing them would falsify supersymmetry? String theory gives at least an answer, with its $10^{300}$ or so different candidates on the landscape. What is "personal opinion" in this question, instead of a simple application of Popper's empirical content?

 

[PeterDonis]

what could falsify supersymmetry?

Failure to discover particles predicted by it. As I understand it, some of the simpler supersymmetric extensions of the SM have already been ruled out by LHC data.

 

[Ilja]

Ok, as far as a particular supersymmetric theory contains definite values for the masses. But this was not exactly my question, because it was I have asked about the explanatory power. Is there some property of the SM (like, say, the three generations) which is explained by supersymmetry?

 

[Dale]

And positivism, which was the leading philosophy of science in the critical time of rejection of ether philosophy, has been rejected as a philosophy of science by Popper 1935.

OK at this point everyone has said their piece. Since both philosophy and "beyond the standard model" are off topic for this forum, it is time to close the thread.