BBC Horizon this week is running an episode How Small is the Universe? with a description that features the usual sort of hype about modern physics:
It is a journey where things don’t just become smaller but also a whole lot weirder. Scientists hope to catch a glimpse of miniature black holes, multiple dimensions and even parallel Universes. As they start to explore this wonderland, where nothing is quite what it seems, they may have to rewrite the fundamental laws of time and space.
Access to the video is restricted to IPs in the UK, so I can’t watch the thing, and should avoid being too critical. One of the two clips though advertises The landscape of String Theory and somehow I doubt that the clip explains why this is pseudo-science. Associated with the show is this article by Andy Parker of ATLAS, which gives the idea that ATLAS is looking for strings:
Strings can vibrate, and this allows us to explain all of the strange fundamental particles which we see as different vibrations of the strings – different notes from a cosmic violin.
So far, so simple – but to explain the particles we know about, the strings have to vibrate in lots of different ways.
Superstring Theory allows them to vibrate in a bizarre space with 11 dimensions – up, down, sideways, “crossways” and 7 other ways!
Experiments at the LHC are looking for evidence that you can move “crossways”. If we can, there could be whole universes, as big and marvellous as our own, sitting just down the road “crossways”.
No mention is made of the fact that the LHC has seen zero evidence for any such thing, or that few if any physicists ever thought there was any real chance it would.
The other experiment invoked is the MAGIC gamma ray telescope, presumably in the context of the search for Lorentz-violating dispersion of gamma rays from gamma ray bursters. This was discussed in an edition of This Week’s Hype from five year’s ago, which featured a Slashdot report that Gamma Ray Anomaly Could Test String Theory. At Scientific American, the story was Hints of a breakdown of relativity theory?, which was about this paper, and contained the news:
Another co-author, string theorist Dimitri Nanopoulos of Texas A&M, writes to me: “I am very excited about this, because as you know we suggested this effect about ten years ago and we have follow through with several analyses and/or improvement on theory. Notice that the 0.4 x 1018 GeV is the typical string scale!!!!”
Since 2007 there have been a series of much more sensitive results from Fermi ruling out the quantum gravity interpretation of the MAGIC observations (see e.g. here, here, here and here.)
Since I can’t watch the video, I don’t know what the BBC has to say about MAGIC’s results, in particular whether the show explains the story of the 2007 claims and how they were later shown not to have anything to do with space-time structure by the newer Fermi observations.
Update: I did just get a chance to watch the program. It was very well made, with the first half quite interesting, featuring the LHC and some atomic-physics scale experiments I would have loved to hear more about. About half-way through though, it started to go off the rails, with the usual kinds of problems. The extra dimensions at the LHC stuff made no mention of the fact that even string theorists see no good reason for them to show up at this scale, and the results to date confirm this. The Mike Green segment was pretty much pure string theory/multiverse hype. Reference to the “mind-boggling predictions” of string theory misses the main problem, that there are no predictions. In particular, no predictions about the gamma-ray dispersion MAGIC is looking for, which ended the show. The 5 second discrepancy described at the end in MAGIC 2005 observations I suspect has been shown to not be plausibly due to such dispersion by later Fermi results which went unmentioned.
Darn, when will these guys finally learn to NOT mention any tabood s-words in public ! Just stop talking to any science journalists, in publicly available videos, on TV, in newspapers, etc about such things and the world, in particular the blogosphere, will be much more peaceful and constructive …
I thought these Magic/Fermi results about searches for violation of lorentz invariance etc test loop quantum gravity and related models. I didn’t know they are a test of string theory.
I live in the UK and follow “Not even wrong” I also watched the program. The BBC does try to look at all angles, the program by enlarge is looking at the topic as a whole and was overall quite good. I would recommend trying to obtain a copy of the program somehow and bear in mind the program is televised on a nation channel and therefore has to be accessible. I would need to watch it again to pass any real comment as I often ignore/block out conjuncture on string theory.
Overall the programme was OK, but there was a distinct failure to separate solid science from speculation, as is often the case. There was no dissenting voice on the possibility of mini-black holes at the LHC, the string theory landscape was treated credulously and there was no mention Fermi in the context of the MAGIC results.
I watched the Horizon programme yesterday. The usual science-doc guff of louche theorists sipping coffee in agreeable European locations, but tempered by a refreshing emphasis on experimental verification with a lot of footage of serious looking hardware, and even people actually measuring things. The theorists were given a generous platform, but weren’t treated with complete reverence.
Here’s some of the commentary on string theory (your favourite, I know): “It’s a beautifully neat idea […] There are, however, one or two problems […] These strings are so small that no one has ever seen anything remotely stringy.” On the landscape: “If they could find the right solution [ironic pause] the right one out of one followed by five hundred zeros [another ironic pause] we’d have a neat explanation for everything in our universe.” Summing up string theory: “For now, string theory remains a theory, with no experimental evidence for any of its mind-boggling predictions […] To stand a chance of seeing strings we’d need a particle accelerator one million billion times bigger than the LHC” (at this point the camera sweeps away into footage of distant cable cars as we leave Michael Green, apparently stranded in some rarefied cloud-shrouded alpine idly, like some well meaning guru condemned endlessly to shuffle the arcane symbols of his beautiful but otherwise utterly unworldly theory).
Lots of stuff on MAGIC in the context of the QG segment – no mention of other (Fermi) measurements. To be as generous to the programme makers as possible you could say they were using MAGIC as an illustration of how to indirectly test theories (QG in this case) that operate on scales so stupefyingly small they could never be tested directly. As an illustration of the ideas involved I think this worked rather well, and kept in touch with their emphasis on experiment and testing… but it’s a shame they didn’t mention what the actual observation (now) appears to be!
The comments above are accurate, I also watched the programme on Monday night and thought it was a reasonably accurate popularisation (“…for now, String Theory remains a theory, with no experimental evidence for any of its mind-boggling predictions”). But as others have mentioned, no recent results challenging the original 2005 MAGIC results were presented, (I was sufficiently confused that I had to go check references afterwards regarding gamma ray dispersion results)
The best bits were the sequences showing the lab hardware, especially Thorsten Schmidt’s X-Ray beam apparatus to split an electron into orbitrons and spinons (quasiparticles).
@Mike Mathison
In your transcript of the program:
“For now, string theory remains a theory, with no experimental evidence for any of its mind-boggling predictions…”
Are you sure the comma after “theory” belongs there? It makes a big difference in the meaning. With the comma, the entire concept of the term theory is demeaned as something without evidence (a widely held popular perception).
Damn! Only watched it for three minutes and then switched away – would have enjoyed seeing the Swiss Light Source and my colleague Thorsten at a beamline that I have worked at. Could not have expected that the programmers would juxtapose orbitons observed via RIXS (resonant inelastic x-ray scattering) and the non-predictions of the string theory landscape.
Yes, the programme was a bit of a mishmash, along with some cool hardware they had Michael Green going on about how the tiniest particle could also be the whole universe (I guess he was referrring to dualities), and a rock-music sequence with Dr Giovanni Amelino-Camelia riding a moped through Rome and then talking gibberish about space-time (“what is space-time, you know? [etc]…, you see what I’m trying to say? It is very tricky.” )
Schmidt’s experiment is shown from ~22:00 onwards ( I mistakenly wrote ‘orbitrons’ above it, it should be ‘orbiton’ as Cormac wrote)
I did get to watch the program, and just added something to the blog about it. The first half was very good, and I would have loved to hear more about the experiment Cormac mentions, instead of the “trip down the rabbit hole” that followed.
As Shantanu mentions, the Lorentz symmetry violations MAGIC is looking for are something some string theorists (e.g. Nanopoulos) claim as evidence for string theory, others claim string theory predicts no such violations. Same with pretty much everything else (another good example is variation of fundamental constants). Since the program featured string theory and MAGIC, it would have been a good idea to address this issue.
@BMJ – I put in the comma to try to reflect the delivery of the spoken commentary – and listening to it again I’d also say there’s some pronounced emphasis on the second occurrence of theory: “[…] but for now [slight pause] string theory remains a *theory* [slight pause] with no experimental evidence for any of its mind-boggling predictions […].” Obviously I can’t speak for the intended meaning of the writers of the commentary, or for the person who delivered it. The sentence in question begins around 40 minutes and 7 seconds.
Peter: If you are interested in the experiments on spin-orbital separation mentioned above (and in the program), concerning the fractionalisation of the electron into distinct quasiparticles, then the relevant paper was published in Nature in April. The observation of orbitons in Sr2CuO3 was obtained via RIXS measurements by Schlappa et al (i.e. Thorsten Schmitt and co-workers).
See the nature article, and even the supplementary data which has some of the more interesting information for the specialist.
For those not in the field then the BBC news report can be read instead.
Is the Wang particle part of the hype?
lun,
Looks suspiciously like the “Wang particle” is its very own form of hype, but I know nothing about it.
In related news, apparently the multiverse killed god