Sunday, December 27, 2015

Dear Dr B: Is string theory science?

This question was asked by Scientific American, hovering over an article by Davide Castelvecchi.

They should have asked Ethan Siegel. Because a few days ago he strayed from the path of awesome news about the universe to inform his readership that “String Theory is not Science.” Unlike Davide however, Ethan has not yet learned the fine art of not expressing opinions that marks the true science writer. And so Ethan dismayed Peter Woit, Lubos Motl, and me in one sweep. That’s a noteworthy achievement, Ethan!

Upon my inquiry (essentially a polite version of “wtf?”) Ethan clarified that he meant string theory has no scientific evidence speaking for it and changed the title to “Why String Theory Is Not A Scientific Theory.” (See URL for original title.)

Now, Ethan is wrong with believing that string theory doesn’t have evidence speaking for it and I’ll come to this in a minute. But the main reason for his misleading title, even after the correction, is a self-induced problem of US science communicators. In reaction to an often raised Creationist’s claim that Darwinian natural selection is “just a theory,” they have bent over backwards trying to convince the public that scientists use the word “theory” to mean an explanation that has been confirmed by evidence to high accuracy. Unfortunately, that’s not how scientists actually use the word, have never used it, and will probably never use it.

Scientists don’t name their research programs following certain rules. Instead, which expression sticks is mostly coincidence. Brans-Dicke theory, Scalar-Tensor theory, terror management theory, or recapitulation theory, are but a few examples of “theories” that have little or no evidence speaking in their favor. Maybe that shouldn’t be so. Maybe “theory” should be a title reserved only for explanations widely accepted in the scientific community. But looking up definitions before assigning names isn’t how language works. Peanuts also aren’t nuts (they are legumes), and neither are Cashews (they are seeds). But, really, who gives a damn?

Speaking of nuts, the sensible reaction to the “just a theory” claim is not to conjure up rules according to which scientists allegedly use one word or the other, but to point out that any consistent explanation is better than a collection of 2000 years old fairy tales that are neither internally consistent nor consistent with observation, and thus an entirely useless waste of time.

And science really is all about finding useful explanations for observations, where “useful” means that they increase our understanding of the world around us and/or allow us to shape nature to our benefits. To find these useful explanations, scientists employ the often-quoted method of proposing hypotheses and subsequently testing them. The role of theory development in this is to identify the hypotheses which are most promising and thus deserve being put to test.

This pre-selection of hypotheses is a step often left out in the description of the scientific method, but it is highly relevant, and its relevance has only increased in the last decades. We cannot possibly test all randomly produced hypotheses – we neither have the time nor the resources. All fields of science therefore have tight quality controls for which hypotheses are worth paying attention to. The more costly experimental test of new hypotheses becomes, the more relevant is this hypotheses pre-selection. And it is in this step where non-empirical theory assessment enters.

Non-empirical theory assessment was topic of the workshop that Davide Castelvecchi’s SciAm article reported on. (For more information about the workshop, see also Natalie Wolchover’s summary in Quanta, and my summary on Starts with a Bang.) Non-empirical theory assessment is the use of criteria that scientists draw upon to judge on the promise of a theory before it can be put to experimental test.

This isn’t new. Theoretical physicists have always used non-empirical assessment. What is new is that in foundational physics it has remained the only assessment for decades, which hugely inflates the potential impact of even smallest mistakes. As long as we have frequent empirical assessment, faulty non-empirical assessment cannot lead theorists far astray. But take away the empirical test, and non-empirical assessment requires utmost objectivity in judgement or we will end up in a completely wrong place.

Richard Dawid, one of the organizers of the Munich workshop, has, in a recent book, summarized some non-empirical criteria that practitioners list in favor of string theory. It is an interesting book, but of little practical use because it doesn’t also assess other theories (so the scientist complains about the philosopher).

String theory arguably has empirical evidence speaking for it because it is compatible with the theories that we know, the standard model and general relativity. The problem is though that, for what the evidence is concerned, string theory so far isn’t any better than the existing theories. There isn’t a single piece of data that string theory explains which the standard model or general relativity doesn’t explain.

The reason many theoretical physicists prefer string theory over the existing theories are purely non-empirical. They consider it a better theory because it unifies all known interactions in a common framework and is believed to solve consistency problems in the existing theories, like the black hole information loss problem and the formation of singularities in general relativity. Whether it is actually correct as a unified theory of all interactions is still unknown. And short of a uniqueness proof, no non-empirical argument will change anything about this.

What is known however is that string theory is intimately related to quantum field theories and gravity, both of which are well-confirmed by evidence. This is why many physicists are convinced that string theory too has some use in the description of nature, even if this use eventually may not be to describe the quantum structure of space and time. And so, in the last decade string theory has become regarded less as a “final theory” and more as mathematical framework to address questions that are difficult or impossible to answer with quantum field theory or general relativity. It yet has to prove its use on these accounts.

Speculation in theory development is a necessary part of the scientific method. If a theory isn’t developed to explain already existing data, there is always a lag between the hypotheses and their tests. String theory is just another such speculation, and it is thereby a normal part of science. I have never met a physicist who claimed that string theory isn’t science. This is a statement I have only come across by people who are not familiar with the field – which is why Ethan’s recent blogpost puzzled me greatly.

No, the question that separates the community is not whether string theory is science. The controversial question is how long is too long to wait for data supporting a theory? Are 30 years too long? Does it make any sense to demand payoff after a certain time?

It doesn’t make any sense to me to force theorists to abandon a research project because experimental test is slow to come by. It seems natural that in the process of knowledge discovery it becomes increasingly harder to find evidence for new theories. What one should do in this case though is not admit defeat on the experimental front and focus solely on the theory, but instead increase efforts to find new evidence that could guide the development of the theory. That, and the non-empirical criteria should be regularly scrutinized to prevent scientists from discarding hypotheses for the wrong reasons.

I am not sure who is responsible for this needlessly provocative title of the SciAm piece, just that it’s most likely not the author, because the same article previously appeared in Nature News with the somewhat more reasonable title “Feuding physicists turn to philosophy for help.” There was, however, not much feud at the workshop, because it was mainly populated by string theory proponents and multiverse opponents, who nodded to each other’s talks. The main feud, as always, will be carried out in the blogosphere...

Tl;dr: Yes, string theory is science. No, this doesn’t mean we know it’s a correct description of nature.

37 comments:

Uncle Al said...

Science is empirical re falsification via Galileo and Popper. Theory absent falsification is applied mathematics. Testing to fail is grant funding risk. 1965 America abandoned performance in education, earning one's living, making books balance, and research discovery absent prior declaration. Decisions are peer votes - conducted by rules, countable, defined riskless. "Quis custodiet ipsos custodes?" Entropy.

String theory is not empirical. 10^(500) or 10^(272,000) string theory vacua are Shrouds of Turin. A vast vote is a discoverable forgery. Atom-scale enantiomorphs vacuum free falling non-identically heal and constrain empirically sterile theory. Don't look! Baryogenesis hides under the rocker panels.

Arun said...

Bee's readers should also read Bee's comments posted on Peter Woit's blog thread: http://www.math.columbia.edu/~woit/wordpress/?p=8214.

Henrique said...

Hi Sabine,
I am not a string theorist, so pardon my ignorance in the following commentary.
In which sense exactly is string theory compatible with the standard model? I thought there were no known CY compactifications that gave rise to it. Moreover, it is not completely clear to me how it jibes with QFT. After all, there are no point-like particles in QFT that should be extended. There are only fields, and Feynman propagators for fields are of course delocalized in position space, i.e. we should not see propagators as particle world-lines that can be extended to world-sheets, right? I'm confused. Lastly, if one resorts to a more modern AdS/CFT take on string theory, I fail to see how it is fully compatible with GR, for we know that GR supports a Universe with a positive cosmological constant - a sign not compatible with AdS/CFT.
Again, I ask these in a spirit of ignorance, not of aggression towards string theory.

But if the answer to these questions is "it is not yet known how ST does this and that", then I believe the problem may be deeper than your description here allows. For not only is there no new experimental evidence, but it would also not be recovering aspects of known science. Thanks

Sabine Hossenfelder said...

Henrique,

Well, Gordon Kane says he knows how to get the standard model from string theory see eg here. Maybe not all string theorists agree with this construction, but I don't think there is much doubt that somewhere in the landscape there is something suitably similar to the standard model. And how to get back GR has been known for a long time. This is not a minor achievement. One that most other approaches to qg have not been able to score on.

Yes, strings are extended, but at low energy you don't resolve this extension, it's far beyond collider reach. At the low energies that we can test, strings are for all practical purposes particles with gauge fields as usual in QFT.

Yes, getting a positive cosmological constant is difficult, but it's possible if you make sufficient effort. I don't really know why you allude to AdS/CFT in this regard though. That you get AdS/CFT in certain limits doesn't mean there are only (asymptotically) AdS spaces in string theory, just that these are the ones that are best understood. There is a lot of effort now going into exteding AdS/CFT to flat or dS space. This however isn't so much to demonstrate that these spaces can be obtained at all but that (ideally) the duality still holds in these (more realistic) cases. Best,

B.

Henrique said...

Thanks for the patient answer Sabine.

Regarding Kane, I am not able to judge his arguments on my own, so I must defer. From what I gather, even string theorists regard Kane's work as dubious, and have referred to some of his arguments as a "shot in the foot of the string theory defence". In more generality, isn't the usual statement about the standard model merely that you can get essentially any low energy physics out of “string vacua”?http://www.math.columbia.edu/~woit/wordpress/?p=8214#comments
I don't know how accurate this statement can be made.

Let me rephrase my QFT question. I was saying that QFT is a theory based on fields, not on point-like particles. Thus one should not worry about extending these points, since they weren't there to begin with. It feels a bit like adding epicycles to an outdated model, although this is admittedly an overly harsh comparison. I was asking if by going back to a non-field type explanation of particles, we are not taking a step back from a well-tested theoretical framework. I understand of course that in low energy the extension of the strings would not be resolvable.

I also understand that string theory recovers GR (the full non-linear theory, right?). I was asking if one shifts their position to a more modern definition of string theory as a theory of quantum gravity in the form of AdS/CFT, as many authors suggest, then one has a big problem with the cosmological constant. But apparently I was mistaken, because I didn't know that there was work showing that the duality can be obtained for non-negative cosmological constants.
Thanks for this once again

P.S. I remember an interview with Ashtekar in which he mentioned that in the early 2000's, when the first hints of a positive cosmological constant were appearing, Witten was going around saying that these experimental results are premature and probably wrong, because it was known from string theory (and I'm assuming AdS/CFT) that the Universe had a negative cosmological constant. Of course they don't say this anymore.

Sabine Hossenfelder said...

Henrique,

That's an interesting quote about Kane... Yes, the usual argument is that you can get anything, so the SM must be somewhere in it. I don't have any reason to doubt this. The SM is not a difficult theory. It's got small gauge groups. Ok, there is chirality, but that is doable.

Regarding QFT, I think talking about fields and points and so on is a distraction. Perturbatively quantized gravity is non-renormalizable. One way to resolve the problem is to get rid of the short-distance contributions, thus going to extended objects helps. No, I don't think that's the only option.

Yes, the full non-linear theory (plus higher order corrections). You misunderstood me on the cc and AdS/CFT. I said that they are trying to extend the duality to flat and dS spaces, not that it has been done. But whether the duality still holds in these spaces is a priori a different question about whether a string theory exists in these spaces to begin with. Best,

B.

DocG said...

My problem with string theory is that it looks like a crude, almost childish effort to reconcile particle and wave, roughly similar to the old effort to square the circle. It's just too simple minded to reduce the fundamental aporia of complementarity to teensy weensy little particles in the form of strings so they can vibrate to produce waves and thus be both particles and waves simultaneously. C'mon, why does any scientist take such a silly idea seriously? It's hard for me to see how all the sophisticated math in the world could turn such a clunky notion into a scientific theory.

kneemo said...

Henrique, string theory is no longer a theory of strings. It has been extended to M-theory, which has only 2-branes and 5-branes. The compactifications used by Kane are ones from M-theory in 11-dimensions, which make use of a 7-dimensional G2-manifold (not a Calabi-Yau space). M-theory, presently, is not yet complete. It is true, much research has shifted to AdS/CFT, but the problem of finding a full non-perturbative formulation of M-theory remains. Along those lines, many surprises remain, and this is the subject of research for those with exceptional motivations. ;)

Uncle Al said...

"The SM is not a difficult theory.... Ok, there is chirality, but that is doable." Boson photons see mirror-symmetric vacuum. Hadronic matter (fermion quarks) has unending chiral discriminations (e.g., baryogenesis.). Nothing constrains two single crystal quartz balls, enantiomorphic space groups right-handed P3(1)21 versus left-handed P3(2)21, from violating the Equivalence Principle at measurable 10^(-12) relative divergence mass/mass. Ditto 95 °C single crystal P3(1)21 versus P3(2)21 benzil (C14H10O2) enthalpies of fusion energy/mass Test spacetime geometry with geometry. Look.

CW said...

Henrique, thank you for asking those questions, and thanks to Sabine for the responses.

I've been meaning to post here or on N.E.W. about string theory's correspondence limit. It's interesting that the term "correspondence limit" is rarely if ever used in this context, in glaring contrast to general relativity's relationship to Newtonian theory (Newton's theory of gravitation and of mechanics).

It's not at all clear that string theory can be said to correspond in the appropriate limit to the full theory of GR. There is a sort of correspondence to the QFT for the linearized theory, going back to the 1970s (which kicked off the whole idea of string theory as a basis for unification). There is also the conclusion that spacetime must be dynamic and governed by the field equation of GR, once string theory is consistently formulated (still in perturbative form) in a 10-dimensional spacetime.

Of course the latter qualification is very important, since the requirement of an N-dimensional spacetime with N > 4 led straight into the problem of finding an appropriate compactification and ultimately to the landscape. I am not aware of a specific paper that picks a compactification "by hand" and shows that classical GR follows from it directly as a unique approximation in an appropriate limit.* Nonetheless, let's assume that such a demonstration exists. One is then left with a correspondence limit that is heavily "parameterized" by the compactification. One might compare this roughly with the Parameterized post-Newtonian (PPN) formalism, except the parameterization is much more complicated and flexible.

Recall that the purpose of the PPN formalism is to organize and compare alternative metric theories of gravity, with GR as one of those theories, and specifically to help evaluate observational tests in the solar system and other near-Newtonian astrophysical systems. From this point of view string theory is a framework for generating alternative "first-order" quantizations of general relativity, many or most of which cannot reproduce the empirical confirmations of classical GR. It follows, given this point of view, that string theory doesn't have a well-defined correspondence limit, and in that sense isn't a single physical theory.

One might take the necessity of the originally assumed N-dimensional spacetime at face value, in which case the prima facie arbitrariness of the compactification is a big problem—unless one stops worrying and learns to love the Landscape. Of course one must ask why this situation isn't simply an indication that string theory is fundamentally flawed as a physical theory as well as an approach to unification.

One might suppose that certain aspects of it must survive in another approach to the problem, and use that as a partial guide to finding such an approach, while admitting once and for all that string theory itself is a failure. Given the vast amount of work on these problems over the past 40+ years there are probably hundreds of papers in existence that can be understood in exactly this spirit.

(* A pointer to one or more references would be appreciated, if there are such.)

Giotis said...

This was a logical and balanced exposition.

In any case I'm not sure whether various irrelevant baboons and mountain gorillas have understood the full picture.

String theory is not just another theory that may or may not be verified in the future, that's not the point anymore. Due to its intimate connection to QFT( and CFT) machinery and the fact that it is a successful extrapolation and continuation of it, it is here to stay forever.

I mean this is already happening, it's a done deal and in the near future it would be redundant to label physicists as String theorists like it has become superfluous today to label someone as Quantum Field theorist. The two frameworks are and will be further mixed in such extend that would be impossible for someone to work in the field without knowing the String theory machinery fairly well; it would be simply implied that this is the case and String theory courses will become mandatory at undergraduate level in all Universities.

This is epic and we are living exactly in this time period that this historic transition is taking place.

Haters don't have other choice but to accept the new reality and move on.

akidbelle said...

Giotis,

so, basically, undergraduate will be taught that there is necessarily a graviton in nature; that no other solution can exist (at least without breaking the hole machinery), and the line of research will be to find the missing dimensions - forever. All that with no positive-exclusive proof. I am not defending QFT, it is in the very same situation already.

I understand the time period is just to replace an incomplete explanation with another one - meanwhile an effective theory exists. Fairy tales for fairy tales? I will not live long enough to know but it looks to me more like a fight for power. Is it?

J.

Ivan Kaidashenko said...

Dear Bee, could you answer my little two questions?

1.According to a new estimation [arXiv:1511.03209] there should be about 10^272,000 vacua in string theory. Do not you think that that string theory can predict almost any result?
2. According to the calculations pioneered by Strominger and Vafa, the black hole is nothing but only a combination of strings and branes. Do not you think that all these entropy calculations are nothing but manipulations, jugglings, tricks? Do we know for sure the microstructure of black holes?

Best regards,
Ivan

Sabine Hossenfelder said...

Ivan,

1) No it can't predict arbitrary results. Regardless of which vacuum you use, you will still get some (Lorentz-invariant) qft and gr at low energies. You, as many others, fail to see how much of a difficulty it is to achieve this. Yes, you can get pretty much any combination of gauge symmetries (as long as the groups aren't too large) and nobody knows how to fix the coupling constants (at low energy) or the cosmological constant, other than through anthropic arguments. I think this came as a big disappointment for string theorists. As I said, for what the evidence is concerned, it isn't any better than the theories we already have.

2) I don't know what you mean with that. A calculation is a calculation. Any mathematical manipulation is in the end a tautology, it's just a rearrangement of the assumptions. You may call that juggling if you want, but this doesn't change anything about the result. No, of course we don't know the microstructure of black holes. This isn't observational evidence, but it's one of the points that string theorists like to draw upon as "non-empirical" support for their theory.

Phillip Helbig said...

"1.According to a new estimation [arXiv:1511.03209] there should be about 10^272,000 vacua in string theory. Do not you think that that string theory can predict almost any result?"

There are an infinite number of integers. Do you not think that integers can express all numbers? Of course not; there are rational numbers, irrational numbers, etc. The point is that even something infinite is not necessarily exhaustive.

Ivan Kaidashenko said...

Phillip Helbig said: The point is that even something infinite is not necessarily exhaustive.

This is just the greatest danger. If a theory has infinite solutions, it can predict outcome of any experiment. This means that this theory cannot be refuted at all.

Angus Prain said...

CW - I think you hit the nail on the head there. I am also not a string theorist and these comments and statements that string theory "reproduces" GR have been bugging me. I would really like to be pointed to some kind of work as you descrbe, a well defined (parametrized) limit which shows that spacetime is dynamical and described by an action not ruled out by classical GR tests. I hope someone can shed light on the precise way in which string theory "contans" GR (or modification) as a limit.

Sabine Hossenfelder said...

Angus,

This is an old story. It does not of course 'reproduce' GR in 3+1 dimensions without further assumptions (like compaticification and susy breaking at high enough energy) in case that is what you mean. Have a look at section 1.5 of this summary. Best,

B.

Sabine Hossenfelder said...

Ivan,

I think you didn't actually read or didn't understand Phillip's and my answer. Just because there are infinitely many things of type X doesn't mean X does not have any properties whatsoever. As Phillip says, there are are for example infinitely many integers, but the integers are all... integer. What you are saying is basically, there are infinitely many integers, consequently the integers must contain all real numbers, which is nonsense. Best,

B.

Arun said...

Giotis is absolutely right. However, the relationship of string theory to physics will probably be like relationship of the theory of partial differential equations to Maxwell's electrodynamics.

naivetheorist said...

sabine:

you say " I think talking about fields and points and so on is a distraction. ". well, it wasn't just a distraction to Einstein who not only considered the real possibility of a discontinuum alternative to fields but apparently wanted to develop it but couldn't figure the necessary mathematics (looking at the work by Sorkin and by Wolfram may suggest possible routes, though neither have yet gotten very far to date). here are some statements Einstein made between 1916 (when he was still at his creative peak) and 1954 (just before he died).

"But you have correctly grasped the drawback that the continuum brings. If the molecular view of matter is the correct (appropriate) one, i.e., if a part of the universe is to be represented by a finite number of moving points, then the continuum of the present theory contains too great a manifold of possibilities. I also believe that this too great is responsible for the fact that our present means of description miscarry with the quantum theory. The problem seems to me how one can formulate statements about a discontinuum without calling upon a continuum (space-time) as an aid; the latter should be banned from the theory as a supplementary construction not justified by the essense of the problem, which corresponds to nothing "real". But we still lack the mathematical structure unfortunately. How much I have already plagued myself in this way!"
- letter to Walter Dallenbach, Nov 1916


"In any case, it seems to me that the alternative continuum-discontinuum is a genuine alternative; i.e. there is no compromise here. In [a discontinuum] theory there cannot be space and time, only numbers [...]. It will be especially difficult to elicit something like a spatio-temporal quasi-order from such a schema. I can not picture to myself how the axiomatic framework of such a physics could look [...]. But I hold it as altogether possible that developments will lead there [...]."


"I consider it entirely possible that physics cannot be based upon ... continuous structures. Then nothing will remain of my whole castle in the air including the theory of gravitation, but also nothing of the rest of contemporary physics"


"The problem seems to me how one can formulate statements about a discontinuum without resorting to a continuum (space-time) ... But for this we unfortunately are still lacking the mathematical form. How much I have toiled in this direction already!"

btw - happy holidays!

CW said...

Angus,

To partially echo Sabine's reply, let me quote a very recent comment from 'vmarko' on N.E.W. (Peter Woit's blog):

The trouble with EFT is not experimental, but theoretical: there is no theory! Nobody is able to write down the equations for an effective low-energy quantum theory of gravity. The measure of the gravitational path integral is not well-defined, so the theory does not exist, let alone experimental predictions. This was known back in the ’60s and ’70s, when DeWitt was studying the measure for the gravitational path integral. Already then it was obvious (to the well-informed) that any discussion of QG requires one to formulate a UV completion, precisely because an effective field theory doesn’t exist. If a QG EFT were possible, by now people would have long forgot about strings, LQG and other Planck-scale theories, and be content with an effective low-energy theory.

So, it would be nice if we had a "PPN-like" formalism for a quantum theory of gravity (or parameterized family of theories) that is well-defined and presumptively valid at low energy, mostly reproduces the predictions of classical general relativity, and predicts certain small deviations that we might hope to verify experimentally. The fact is that we don't—and it's not for lack of trying.

Ivan Kaidashenko said...

Sabine said: 2) ... A calculation is a calculation. Any mathematical manipulation is in the end a tautology, it's just a rearrangement of the assumptions. You may call that juggling if you want, but this doesn't change anything about the result. No, of course we don't know the microstructure of black holes. This isn't observational evidence, but it's one of the points that string theorists like to draw upon as "non-empirical" support for their theory.

Dear Sabine, I think that these calculations are done for models in flat space-times which are dual to the string theory on a given black hole background. These calculations say nothing about the real microscopic degrees of freedom responsible for the BH entropy and where they are placed.

Sabine Hossenfelder said...

Ivan,

Sorry, I don't know what you mean. In my understanding, the bh entropy calculations in string theory count the number of ways you can build up such a black hole within the theory. Yes, these are normally static black holes and extremal (or near-extremal) and not particularly realistic. I already said that these calculations have no experimental evidence speaking for them. I merely said that for string theorists they count in favor of their approach. Best,

B.

Ivan Kaidashenko said...

Sabine,

Thanks for your explanation. I mean that all these calculations are done in the limit of weak coupling; that is, instead of a black hole we have a dual object(perturbative strings) in a flat(!) space. The AdS/CFT correspondence also does not explain what are the bulk degrees of freedom and where are they located.

Best regards,
Ivan

Sabine Hossenfelder said...

Ivan,

Sorry, I misread your earlier comment as meaning that what you referred to as 'model' is the black hole whose entropy you want to calculate (which didn't make much sense). Yes, I think what you say is right. I'm not sure why it should bother me that I don't know 'where' the degrees of freedom are located. I would be more bothered if they were localized. (As they seem to be in LQG.) Be that as it may, I don't really understand what you want to express. You seem to be saying that there is something about this which you don't like, but I don't see the relevance for my post. Best,

B.

Ivan Kaidashenko said...

Sabine,

I'm sorry about the mix up. It's my fault.

Best regards,
Ivan

Unknown said...

Well, people use words in different ways. The way I use the word "science" does exclude theories that can only be evaluated (relative to the competition) non-empirically. Such theories belong are some other branch of philosophy. But I don't mean that in a bad way: not all rational, reasonable attempts at getting at truth have to be Science. Indeed I think a lot of interesting physics is not really science, but is still valuable work.

Of course people are allowed to use the word "science" in a broader way. But I suspect there is dark cause behind that usage. In the science-vs-religion debate, the S-team ends up putting science on a pedestal above the "merely philosophical". Then anyone who affiliates with the S-team wants their own theory to count as science, and we accomodate by expanding the definition.

Sabine Hossenfelder said...

Unknown,

You are free of course to use words however you want, but your definition simply doesn't agree with the way the word is commonly used. You are saying that work on any theory under development does not constitute science, and most of the development of general relativity, quantum field theory, and indeed pretty much all of 21st century physics is not science. It's completely nonsensical.

I do agree of course that a theory which can by construction not be tested empirically by any means is not science, but I hope I made it clear that none of the theories under question here are of this type. They are not yet testable. They are testable in principle. Best,

B.

Lucy M said...

Giotis says "In any case I'm not sure whether various irrelevant baboons and mountain gorillas have understood the full picture." the "it is here to stay forever" then "..it's a done deal.." mandatory in schools.."
finally "...This is epic and we are living exactly in this time period that this historic transition is taking place..." Parting words "Haters don't have other choice but to accept the new reality and move on".

You really haven't the first inkling how ridiculous you're being. You have been living in a bubble that has paid your bills and living expenses and given you a good standard of living with plenty of travel, generous vacations, and best of all a safe job for life, that doesn't involve you having to work for a living.

And you think that's going to carry on for ever and ever. But most worthy derision is what you have to believe first in order to believe your for ever and ever story. You believe the future direction and wellbeing of the scientific franchise shall be in your gift to say.

Your field has just wasted 50 years during which time no expense has been spared, other avenues starved. String theorists, including the pioneers have arguable misrepresented the status of string theory's real status within science, and as well as its status as a science (e.g. the fact String Theory CAN NEVER predict, in principle).


There's going to be anger at the lost decades and everything you and the others have said in every context, is public record. If there is the slightest whiff of a possibility that public funds have been secured with misrepresentation, down the line regardless of time gone by, then if history serves anything to go by, laws will be amended and those practices criminalized into the cabinet with all the others embezzlement and fraud, most of which never would have believed it would happen to them.

And if the string community is guilty of that - the faintest whiff of guilt I mean, then it'll all be backdated because fraud laws always are, and all instances retrospectively altered to crimes. And a large amount of the string community will be going to prison for a long time.

This is epic and we are living exactly in this time period that this historic transition is taking place. You need a cup of coffee.

Sabine Hossenfelder said...

Lucy,

Your anger is kind of interesting in its own right, which is why I approved your comment. But I don't think Giotis is a string theorist by profession, so it seems a little misdirected.

Paul said...

@Lucy M

Be reasonable. At least let's not use up our limited public resources dealing with the relatively minor string theorist menace while there are still gangs of psiontologists and frequentists roaming the streets.

Lucy M said...

Dear Sabine - he Aped the gait and won a banana

I find you interesting back. I think you're conflicted; you say conflicting things in different moods and places relating to this. I wondered what it meant but now I understand conflicted is plausibly the most legitimate place to be. Tell him I want my banana back :)

Arun said...

Hi Bee,
http://www.whytrustatheory2015.philosophie.uni-muenchen.de/program/index.html
Why Trust a Theory? videos are online. I watched your talk and since you referred a lot to Radin Dardashti, watched his talk. Then I started on Carlo Rovelli's talk - but a lot of the slides are marked "slide not provided for publication". Do you know by any chance why?
Thanks!
-Arun

Sabine Hossenfelder said...

Arun,

I was told they take copyright very seriously. This is why my slides are full with grey patches - these are images that I used which were not mine (mostly photos of the people who I quoted, so it doesn't really matter). I am guessing if there's a slide where an image couldn't be covered they'd take it out completely.

Arun said...

Hi Bee,

Well, I think they take copyright way too seriously. I can understand graying out of cartoons. I'm not sure they haven't greyed out stuff that comes from Wikimedia (open source license).

They have greyed out book covers in Pagliucci's talk, in slide 34 where he shows the covers of nine key books that have advanced the philosophy of science.

To me, that is remarkably silly, they have no concept of fair use; and I dislike silly people.

-Arun

Sabine Hossenfelder said...

Arun,

They have greyed out images from Wikepedia, at least on my slides. But that's because I wasn't in the mood to look up the references and add them after they asked me to. As I said, it seemed kind of pointless since the images were just there for decoration. Possibly other speakers had the same reaction.