Philip Gibbs points to an impressive piece of string theory hype from British Channel 4 news.
If you watch the clip, you get the latest news about string theory and the LHC: people were getting discouraged about string theory, but now some of its predictions are being confirmed by the LHC. For the extra dimensions to appear, we may have to wait a couple years for when the machine runs at design energy.
Not clear at all where they got this nonsense from.
Update: The source for this seems to be a story by Jonathan Leake in The Sunday Times, entitled Stand by, we may soon enter a new universe (subscription required, but a syndicated version is freely available here). The story has David Evans of Alice trying to promote his experiment with:
The Alice experiment may soon be able to make experimental measurements which, for the first time, can be modelled using the techniques of string theory.
Although the experimental results will not prove string theory to be correct, an accurate prediction would certainly show that the techniques work, could distinguish between different versions of the theory, and perhaps even show whether the theory is going in the right direction.
Given this kind of quote, one can see why the writer completely mixes up string theory unification and string theory as approximate calculational method in heavy-ion physics:
The researchers, at Cern, the European centre for particle physics near Geneva, say results from the Large Hadron Collider suggest it could offer the first experimental test for some aspects of string theory.
Formulated in the 1960s, this theory attempts to describe how all the fundamental forces of nature, such as gravity and electromagnetism, interact with matter.
On paper, the theory has been highly successful, resolving many mathematical problems.
In practice, however, there is no experimental evidence to support its predictions, including the idea that there could be as many as 11 dimensions – the three physical dimensions, time and seven others as yet undiscovered.
At Cern, there are now hopes the LHC may be able to break this impasse.
Then, as usual, the headline writer takes things a step further:
SCIENTISTS have devised the first experiment capable of giving insight into one of the universe’s greatest mysteries: could there be more dimensions than we know about?
So, out-of-control promotional efforts for ALICE are at the bottom of this one.
Umm … it wasn’t as bad as all that, really. There was a reference to expt data at the ALICE detector of collisions of lead ions and the quark-gluon plasma. But others have been talking about ‘applications of string theory’ (or AdS-CFT?) to the QGP for a while. There was a clear statement that string theory has been worked on for years and has made no predictions at all, and this has prompted some scientists (hmm …?) to claim that string theory does not work. There was a statement by the interviewed physicist that ‘if a theory cannot predict anything then it’s not really physics, it’s … (shrug) … philosophy’ (gasp!!). There was quite a bit of ‘data from the LHC may be on to something’ with regard to string theory. It did say towards the end that when the LHC cranks up to top energy then perhaps some evidence for the extra dimensions may be observed (didn’t say what that evidence would be). However, it is indeed not clear why Ch4 would choose to run such a news item now. There was no statement of any new or recent discovery. ALICE/QGP has been around for a while. It may be (speculating here!) a fallout from the ATLAS-CMS rumours that ‘something is afoot at CERN, with the LHC’.
A theory that cannot even get the number of spacetime dimensions right is not generally in good shape, and consequently the only reason for mentioning String Theory when reporting on a scientific experiment is as a sociological phenomenon amongst theorists. The public will eventually realise that they have been misled and what worries me is that then all theorists – not just the String partisan who advised on this piece – will be tarred with the “bullshitter” brush.
Probably the source is the most vocal, and prominent of string theory hypesters, your colleague, Brian Greene. In a recent interview (Jan 24) on NPR he gushes:
“You almost can’t avoid having some version of the multiverse in your studies if you push deeply enough in the mathematical descriptions of the physical universe,” he says. “There are many of us thinking of one version of parallel universe theory or another. If it’s all a lot of nonsense, then it’s a lot of wasted effort going into this far-out idea. But if this idea is correct, it is a fantastic upheaval in our understanding.”
“There are a couple of multiverses that come out of our study of string theory,” Greene says. “Within string theory, the strings that we’re talking about are not the only entities that this theory allows. It also allows objects that look like large flying carpets, or membranes, which are two dimensional surfaces. And what that means, within string theory, is that we may be living on one of those gigantic surfaces, and there can be other surfaces floating out there in space.”
“If we are living on one of these giant membranes, then the following can happen: When you slam particles together — which is what happens at the LHC — some debris from those collisions can be ejected off of our membrane and be ejected into the greater cosmos in which our membrane floats,” he says. “If that happens, that debris will take away some energy. So if we measure the amount of energy just before the protons collide and compare it with the amount of energy just after they collide, if there’s a little less after — and it’s less in just the right way — it would indicate that some had flown off, indicating that this membrane picture is correct.”
Brian has recently been the source of a lot of multiverse hype, but this is a somewhat different category. I’ve identified the source here, see update to posting, and it’s not Brian.
You should have titled this as “This Week’s Leake”.
I remember you excused experimentalists some time ago for not engaging in the string, multiverse and likes nonsense, but clearly this is not the case anymore. Experimentalists too, talk all kinds of nonsense to get attention. Just depressing. This is much worse than any false rumor.
I doubt if you have identified the source correctly. There just doesn’t seem to be time for one reporter (I think that Channel 4 have precisely one science reporter) to have produced a 2 minute magazine article from scratch, even though other journalists probably saw the Sunday Times at 23:00 on Saturday.
It’s more likely that this was picked up from the CERN Courier piece on May 3rd which probably had a parallel Press Release (or David Evans sent out his own Press Release, which seems likely if he is a bit of a self-publicist).
My media advisor says that the lead-in (the voice-over on the stock LHC film) was probably written by a sub-editor to link to previous LHC coverage, so it would mention things said previously. Since the public preception is that LHC is meant to find “Higgs” and “Strings” it’s not surprising it was mainly about strings.
Overall, I thought it was fairly constructive. Clearly, some experimentalists think that string theories are now testable to some extent and Evans was clear about the priority of experiment over speculation in physics (although he offended my wife by implying that String Theory would be philosophy if it wasn’t verified: she is a philosopher).
I chance to recollect that one of the more fully worked out string theories makes some predictions for the QGP which I think this experiment may well be at variance with.
So it looks like “Game On” for the experimentalists. If my recollection of being a theorist amongst experimentalists is accurate, many experimentalists will take great pleasure in kicking down any theoretical edifice. Looking in Particle Data Tables “Cross Sections” suggests that some people have been working hard at trying to extract testable predicitons from a variety of String theories.
Happy Days! I wish I was there.
“Clearly, some experimentalists think that string theories are now testable to some extent and Evans was clear about the priority of experiment over speculation in physics”
If there are experimentalists thinking that, too bad for them. There is no such thing as testing String Theory at all.
The “public perception” that the LHC is meant to find “Strings” is the problem, since this is simply not true. Claims that heavy-ion physics experiments at the LHC will “test string theory” are heavily over-blown, and part of an effort to mislead the public by generating exactly this sort of completely false story in the press. The supposed application of AdS/CFT approximation methods to certain phenomena in heavy-ion physics has nothing at all to do with string theory unification. The physicists involved here are well aware of this, but happily help generate false news stories like this one.
It’s too much of a waste of time to keep rewriting this same point every time a new bogus press story like this one appears. For some idea of the scale of the problem, click on my blog category “This Week’s Hype” to get an idea of how long and intensively this dishonest campaign has been going on.
“The supposed application of AdS/CFT approximation methods to certain phenomena in heavy-ion physics has nothing at all to do with string theory unification”
More importand ST is a theory of Quantum Gravity and AdS/CFT via ST is closely related to Quantum Gravity.
So AdS/CFT and it’s verification is very important for ST as a theory of QG.
QGP is just another application…
“QGP is just another application…” — how many other applications are there?
It appears that this news item is an attempt by ALICE to gain a share of the spotlight. Rumours have circulated that ATLAS has “seen something” (and CMS is checking its data to confirm) and every false lead gets reported or blogged to fever pitch (yes?). And (horror!) if the “thing” should prove to be true, then ATLAS/CMS/CERN will grab ALL of the headlines. Possibly also all of the LHC beam time. Alice will traipse in Wonderland totally unnoticed. So better to call some attention to oneself. And so to string theory … who in the taxpaying public cares about turning lead ions into pancakes? It appears now that the current rumour from ATLAS is not true … there will be others.
the point is if AdS/CFT cannot make ST explain anything for its own, it´s a test of equivalence. It´s like if Einstein came with the theory of relativity and said that the only experimental test he has is that in particular cases his theory is equivalent to Newton´s… This is the same thing, so NOT a experimental test. A test would be something that QFT cannot make it and ST can but this is something by definition AdS/CFT will never be able to make it. So, the story so far is the same.
To supplement Bernhard’s comment:
We are pretty sure we know what the theory is that governs heavy-ion physics, QCD. Claims that ALICE is “testing” some theory aren’t about testing the underlying theory, but about testing whether some string theory-AdS/CFT inspired model reproduces QCD approximately in some specific situation or not. If ALICE doesn’t find agreement with the predictions of a particular string theory-AdS/CFT based model, it doesn’t mean QCD is wrong, it doesn’t mean string theory is wrong, and it doesn’t even mean the AdS/CFT correspondence is wrong. This is not a “test of string theory”. All it means is that, for the specific phenomenon checked, the model turns out to be useful (to some approximation), or not.
Claiming that you can get from this situation to using the LHC to test the idea of 11 dimensions and string theory unification, which has nothing to do with any of the above, is just absurd.
Why all of the hush, hush. I would think they would post everything there learning and attempting real time! It not like anyone else has the equipment to outdo or discover something first. Science is for all mankind.
I think you’re referring to an earlier posting. But one thing to keep in mind is that there is a competition here. ATLAS is only one of two big general purpose detectors, very much in competition with the other one. One reason for keeping their internal documents out of the public eye is to keep their competitors from reading them. This competition is scientifically valuable since it means that they are under pressure both to get a result as soon as they can, AND to get it right.
all of the LHC experiments and all accelerator based experiments are under extreme pressure to discover *something*. because if they don’t, LHC is probably the last of its kind and even running it to the end will be questionable.
it has become a multi-billion $ business and that is generally not healthy.
Peter and Bernhard,
Nobody talks about testing string theory in the strict sense.
People are talking about circumstantial evidence from different areas of ST which in time could pile up and boost our confidence to the general framework.
I think the article has been written in this spirit. You could tell this from the title which is rather conservative.
I quote: ‘SCIENTISTS have devised the first experiment capable of giving insight…’
This is quite an honest statement I think especially for a headline .
You remind me of Polchinski defending ST by saying that “String theorists have a strong sense that they are discovering something, not inventing it”.
I’m sorry to say I am very much not convinced by string theorists feelings, nor do I agree with you that one gets ANY insight that there could be 11 dimensions because of a particular string theory-AdS/CFT based model might agree with QCD. I think there is no logical conclusion one can draw from this.
On the other hand, if you get such an insight, whatever you mean by that, than I guess we could spread the news that if this “test” fails you will get the insight that there is no such thing as 11 dimensions, right?
It’s true that the LHC experiments are under a lot of pressure to discover something new. It’s also true that they’re under just as much pressure to not make a mistake, with the competition between detectors ensuring that possible mistakes will be vigorously pursued by someone with a huge interest in showing them wrong.
It is true though that the pressures to find funding for these experiments might explain why the string theory hype campaigns sometimes conducted on their behalf.
I heard one of the CERN management guys say that he hopes they find the Higgs, because he promised the politicians that they would. But it seems that not finding it would be bigger news–kind of a null Michelson-Morley-type result that would blow up everything. So I don’t think they should worry too much about anything but inconclusive findings.