Every summer CERN runs a summer student programme, designed to bring in a group of students to participate in scientific activities at CERN and provide lectures for them about the basics and latest state of the field of high energy physics. Because of the COVID situation, this summer they have not been able to bring students in, but are providing instructional lectures and Q and A’s. This year’s sessions are based on having students follow materials from last year’s lectures, followed by a Q and A to answer their questions.
One of the topics the students are presented is What is String Theory?, and you can watch the 2019 video or look at the slides. Timo Weigand’s presentation can be accurately described as pure, unadulterated hype, with not a hint of the existence of any significant problem with ideas presented. In the Q and A yesterday, Weigand did come up with a new piece of “evidence for string theory”: it “predicts” no continuous spin representations.
I can’t begin to understand why anyone thinks it’s all right for CERN to subject impressionable students to this kind of thing. Someone, not me, should be complaining to the organizers and to CERN management.
This is unfortunately now an all too common example of what passes for “Sci Comm” in much of the field of fundamental physics: endless repetition of old discredited arguments in favor of a failed theory, coupled with pretending not to know about what is wrong with these arguments. The field that was once one of the greatest examples of the power of the human mind and the strength of the scientific method has become something very different and quite dangerous: all-too-visible ammunition for those who want to make the case that scientists are as deluded and tribalistic as anyone else, so not to be trusted.
When I was a summer student at CERN in the 1980s, the lectures for the students were completely professional. This year, Weigand’s last slide, with his summary, states: “String theory is a maximally economic quantum theory of gravity, gauge interactions and matter.” A theory that adds 7 spatial dimensions and adds supersymmetry seems to give the impression that maybe it might just not be maximally economic. Weigand also writes on the same slide: “Assumption of stringlike nature of particles leads to calculable theory without UV divergences.” What a pity that he had no time to explain the way to calculate elementary particle masses and coupling constants in this calculable theory. Possibly the margin on the slides was too narrow to write the calculation down?
Gianni,
The “maximally economic” description also struck me. It’s kind of like listening to our current President: hard to figure out whether the no-relation-to-reality claims you’re hearing are intentionally dishonest or just delusional.
Students aren’t remotely as impressionable as you seem to think. Indeed, the most encouraging feedback I have gotten after the publication of my book came from students complaining that they are being taught useless nonsense. The kids, I think, will be alright. Trouble is, if we wait for them to grow up, we’ll see 20 more years of time wasted on failed theories.
This is why I think the key factor to change is public pressure. The hurdle here is that few people feel qualified to comment on what is going on in the foundations of physics. So, science communication (like you do) matters a big deal by explaining to non-experts just what is happening, why it’s a problem, and why they need to call bullshit on it.
I heard various misunderstandings while playing soccer with summer students. The most bizarre, around 2015, was their firm belief that CERN had planned LHC run1 for discovering the Higgs, and LHC run2 for discovering SUSY/new physics.
Sabine Hossenfelder,
It’s not that I think most students believe this kind of hype, although I think it does have some effect of encouraging smarter students not to enter the field, credulous ones to enter it.
The most serious problem with this is the same problem with having a country’s leader every day say things that are clearly untrue. It’s not that most people start believing the untrue things, it’s that the fact that he’s doing it is an announcement that truth no longer matters. Instead, what matters is what’s convenient for those in power, and everyone needs to now accommodate to that reality.
Alessandro Strumia,
Every so often I take a look at what people were saying at various stages in the LHC history. Just happened to look at this, from 2011
https://www.math.columbia.edu/~woit/wordpress/?p=3492
You come off well
“Privately, a lot of people think that the situation is not good for SUSY,” says Alessandro Strumia
Arkani-Hamed at the time was furiously back-pedaling from his 2005 claim that the SUSY question would be settled after one year of LHC data. John Ellis was saying that he would abandon SUSY if it hadn’t shown up by late 2012. You’re right that around this time the pre-LHC storyline that “SUSY will be easy to see, the Higgs coming much later” had already started to be inverted, with Arkani-Hamed then changing his tune to “it will take until around 2020 to know about SUSY”.
It’s not possible to do science indefinitely without empirical checks. If HEP is a victim of its own success, it’s not hard to see why. What physicists have achieved in the past century or so is nothing short of staggering. Who wouldn’t be irrationally inspired by what the human mind can achieve. But we’re wired to believe, and no one ought never to assume striving for brilliance and rationality is enough. Trusting in the strength of other minds is a comfort we instinctively seek, and a luxury we can never afford. Unfortunately, that may mean setting aside the grandest objectives for the foreseeable future, and being content with only the answers nature will yield in the present. I imagine it’s difficult to maintain that level of discipline and restraint when it makes one an apostate and forces them to leave the fold.
Harder still to take the notion seriously, perhaps, when lesser minds such as mine have the chutzpah to chime in with advice. But the lessons of history are clear enough that genius isn’t necessary. Lacking it may even be protective. One can never forget they’re only human.
LMMI,
I’m afraid that what has happened is that the “string theory” community has already taken your advice, setting aside actually working on unification as hopeless until something new comes from experiment.
The problem is not just that they’ve given up, but that they have coupled this with an argument designed to avoid admitting that this giving up is a failure. The currently promoted ideology is that, whatever it is, “string theory” is not a failed idea, but is our “best hope”, and that this “best hope” has shown that the problem is hopeless (the landscape), so everyone should give up.
@Sabine: some students may think they are taught bullshit, but not all of them, at least not the master students. How could they be aware of this anyway ? This propaganda comes from the place where the Higgs boson has been discovered, not from some remote university in a country with no research tradition.
This kind of hype is problematic when students ask for a master thesis (having in perspective a PhD). I am in a mathematical-physics group, inside a math department. Every year we have students from the physics department asking us for a master thesis, because they found that their courses in physics were leaving aside too many mathematical details. Some of them are hesitating between say, a master thesis on supergravity or supersymmetry in physics, or some subjects of mathematical physics we may propose. What should we say ? SUSY is dead, don’t listen to hype, come to maths ? (knowing that the job situation in math-physics is very difficult).
Am I in position to say: don’t listen to what you might heard from the CERN lectures, this is pure propaganda ?
Peter,
Juggling axes is dangerous. In contrast, saying that fundamental physics has become “quite dangerous” is a hyperbolic appeal to fear.
Calling ideas “dangerous” is a common trope and is a pet-peeve of mine. Nobody who criticizes an academic position as being “dangerous” ever traces the line of causation that leads to grad students (or whomever) being maimed or killed. Not even paper cuts. Because if they tried, they would suddenly appear hopelessly speculative and foolish. Let’s not degrade our arguments in this way! Call it “counter-productive,” not “dangerous.” Don’t make appeals to fear.
In other respects, please keep up the good work.
Martin,
Maybe “dangerous” is not the right word, but neither is “counter-productive”. What’s getting maimed or killed is not any person, but the credibility of the subject. This is going to get worse the longer the hype campaign and refusal to admit an idea doesn’t work goes on.
Peter,
“quite dangerous” -> “damaging to the scientific endeavor”
Well, there’s different levels “giving up”, I suppose. Maybe, for instance, there’s giving up on the notion one should devote a lot more effort to studying ways to “unify the fundamental forces” in the absence of some more obvious empirical indication that line of inquiry is going to lead somewhere. Landscapology is in its own league of capitulation. Its practitioners have decided unification is so important that empiricism itself ought not to get in the way of achieving it.
Can’t one eschew GUTs or TOEs for the time being and still do first-rate HEP without giving up on science altogether? I’m still waiting for someone to make an exciting public pitch for determining the shape of the Higgs potential that doesn’t promise far more than it might deliver. My understanding is precision measurement of the Higgs self-interaction is fascinating “new physics” in its own right (being completely unlike any other interaction in the Standard Model).
It’s giving up on the addiction to, and perhaps a “belief system” based on the notion of a “Final Theory” I was thinking of.
Physics is less prone to groupthink. At some point as a student you must develop a spine and go up against your mentor. I remember winning an argument with my advisor (effin’ Nobel Laureate!) something to do with polarized electrons. My students have gone to the mat about machine learning and artificial intelligence in data analysis until I cried uncle. I am sure the same happens with string theory and SUSY etc. in the theory community. Physics students may be many things but they are not sheep.
As I see it, the maximum responsibility lies within the string theorists themselves.
Not with teachers, not with students and not with “scientific” journalists.
If they (especially the “top” ones) came out publicly in their conferences, and stated that ST is not the “final theory” they were looking for, that things/ideas have taken a different route and that ST, as it is, needs some big changes (has to be clearly rethought, as some do acknowledge privately…), the situation might start getting better in the HEP world.
Also, maybe everyone should be a bit more humble, and settle for something less than a final TOE which, IMHO, might be too much for us to ask for, and might very well not even exist.
Weigand’s presentation was an absolute joke.
Stop the String Theory bashing ! It’s “not even funny”.
String theory is dead and we will have in a few years the first generation of high energy theoretical physicist without a single interesting article in their whole sad career (mid 80’s-mid 2020’s)
We should instead discuss about recent articles and emphasize on :
– neutrino (https://en.wikipedia.org/wiki/List_of_neutrino_experiments)
– g-2 (Fermilab E989) vs LatticeQCD
– cosmological simulations vs observational cosmology (and the cool new toys : Euclid, LSST, …)
– syntax and models of type theories, infinite categories, abstract homotopy
– periods and motives
it’s not hype-driven development… these are just (some of) the 2020’s healthy scientific communities
“la fécondité se reconnaît par la progéniture”
The problem with saying “the students are smart and not impressionable; they’ll be all right” is that the people who decide which students become professors are the string theorists who have bought into the failed theory, and they’re going to promote the students who aren’t saying that string theory has reached a dead-end.
So we may have to put up with another generation of string theorists before we can get fundamental physics on a reasonable track again.
@PeterShor
The CERN summer students are not — generally speaking — future theorists of any kind. They’re future experimentalists, and the experimentalists who’ll be hiring them are not noted for being especially friendly to string theory. (Yes, many of them liked the idea of weak-scale SUSY, but I don’t know any who were particularly heartbroken when it turned out to be wrong.) Also, how much of an impact do you think a single lecture on string theory is going to have on people who spend all the rest of their days working on the nitty gritty details of a high energy experiment?
A.J.,
I think you’re right that this is mostly an audience of potential experimentalists not theorists. But then, since there’s no relevance to any experiment, why do you think the organizers thought lectures on string theory of this kind were a good idea? I’m seriously trying to understand what is going on in people’s minds. “String theory” seems to have become some bizarre totem or something, completely divorced from evaluation as conventional science, but brought out to wow certain groups of people. This is starting to seem to me understandable only as some sort of religious or tribal ritual, a parading of mysterious golden tablets that have 40 years of the tribe’s hopes for the future invested in them. Why does anyone think this is what science looks like?
Peter,
I was there about 20 years ago, and was a bit of an oddball for having much interest in theory or mathematics. Those students were quite serious experimentalists. I’ve kept in touch with many of them over the years, and the number who’ve become successful HEP experimentalists is a bit shocking. I’m used to theory, where maybe 1/30 got past the postdoc. For the CERN summies, it was at least 10x that. Some of them are even giving summer lectures this year.
In any case, the student lectures are a mix of Basic Practical Thing You Must Know to Do Real Physics and Glimpse Into Another Nearby But Probably Less Important Field of Physics. At least when I was there, theory wasn’t presented as anything to idolize.
About 8 years ago my daughter and I were at a University Open Day in Sydney to choose her studies in science. As we walked around different faculties, we came across the Physics department where we met some eager young Physics students of the University. They were trying to appeal to my daughter to do Physics. One of their main selling point was that they do research in String Theory. I remember feeling disappointed, I thought, is String Theory now really the ‘Poster Boy’ of Physics?
PS.
My daughter has now finished her Masters Degree in Biology and Environmental Sciences.
“Someone, not me, should be complaining to the organizers and to CERN management.”
I agree, but it is very nontrivial to find someone with nothing to lose to make such a complaint. Anyone without a permanent position is ruled out for the fear of backlash, and even if you have a permanent position there are political reasons not to do it. Experimentalist professors who are group leaders won’t feel comfortable or judge they have the right credentials to make such a complaint, theorists won’t want to “have a problem” with their friends, even those who think this is pure BS. And, especially if you work at CERN (be as staff or user), which is basically a small town, you won’t want this attention drawn to you.
Peter,
Purely by accident, a recent Google search included a link to one of your old posts:
Two Cultures https://www.math.columbia.edu/~woit/wordpress/?p=6208
Just out of curiosity, following links you provided there, and reading (and remembering) what people back in 2013 were saying “must be true”, and “what we’ve known for decades”, is rather scary.
I recently came across a quote attributed to Saul Perlmutter that seems appropriate here (and to much that is going on in the world today):
“People forget that when we talk about the scientific method, we don’t mean a finished product. … Science is an ongoing race between our inventing ways to fool ourselves, and our inventing ways to avoid fooling ourselves.”
Perhaps that’s the lesson that should be communicated to those summer students at CERN: that the latter should be their goal, with Weigand’s presentation a case in point of the former.
Unfortunately, the former often seems to be winning over the latter lately, in HEP and elsewhere, despite ongoing evidence. This is not “new news”, but for an example of more hard data re. SUSY from CERN, here’s some of the latest published results, in PRL:
Search for Heavy Higgs Bosons Decaying into Two Tau Leptons with the ATLAS Detector Using pp Collisions at √s=13 TeV
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.125.051801
I’ve just finished my PhD in HEP. I must say many students are, in fact, quite impressionable. I used to think I wanted to do research on ST until I started attending lectures by the big fishes of the community (including the superstring winter school at CERN)… It was a total disappointment being told about the swampland conjectures and exotic string compactifications without any reference to real physics and being surrounded by very arrogant students.
I’ve also got to know many students who sadly label ST and the like as “real” theoretical physics, as the path to follow, regarding (for example) solid state physics as less relevant. Many also think that phenomenology is BS and you are an idiot if you don’t do research in sugra/extended susy/ads-cft. It seems that many just follow the fame and the hype of the big names in the field. Their PhD advisors get perpetuated by these young people, so I think the picture is not going to change any soon.
A new article full of (not so subtle) String Theory hype: 🙂
https://www.symmetrymagazine.org/article/taking-a-risk-on-theoretical-physics
Off topic but good read https://www.nature.com/articles/d41586-020-02297-2
Juan, in saying “many students are, in fact, quite impressionable”, has hit the nail almost on the head. I would suggest “many” be replaced by “almost all”. The notion that young HEPers are straining to break free of the strictures imposed by their presumed elder betters is charmingly naive.
Maximally economic? A theory that predicts 6, 7 or 22 extra spatial dimensions, of which there is no empirical evidence whatsoever? A theory that doubles the number of fundamental particles, without being able to predicts their masses, and for the existence of which, again, empirical evidence is sorely missing? A theory that posits a preposterously large number of possible different vacua, all of them just as likely within the context of the theory? A theory that takes the values of fundamental physical constants as deus ex machina-given? A theory that evolves in a deus ex machina-given space-time? This is a maximally economic theory? What is this guy smoking?
I, for one, really, really hope that theoretical physicists will eventually be able to do much better than that.