In the News

In which celebrity culture comes to particle physics. ------------ It's been about six months since we had a big flurry of Higgs Boson stories, and as enjoyable as the relative quiet has been, it means we're due for another run. And, predictably enough, the usual suspects are stoking speculation about what, exactly, will be officially revealed in a few weeks at the summer particle physics meetings. This spilled over into the rest of the social media universe, with the joke hashtag #HiggsRumors becoming a trending topic on Twitter for a little while last night. As is also sadly predictable,…
So, the infamous OPERA result for neutrino speeds seems to be conclusively disproven, traced to a problem with a timing signal. Matt Strassler has a very nice explanation of the test that shows that the whole thing can almost certainly be traced to a timing error that cropped up in 2008. This problem is generally described as resulting from a "loose fiber optic cable," and Matthew Francis's reaction is fairly typical The main culprit was a fiber optic cable that was slightly out of alignment. This is not quite a "loose wire", as it sometimes has been described: it's far more subtle and harder…
Richard Feyman famously once said that the double-slit experiment done with electrons contains everything that's "'at the heart of quantum physics." It shows both particle and wave character very clearly: the individual electrons are detected one at a time, like particles, but the result of a huge number of detections clearly traces out an interference pattern, which is unambiguously a wave phenomenon. The experiment has been done lots of times, but a particularly nice realization of it comes from Hitachi's R&D department, where you can see both still images and video of their experiment…
It's been a while since I did any ResearchBlogging posts, because it turns out that having an infant and a toddler really cuts into your blogging time. Who knew? I keep meaning to get back to it, though, and there was a flurry of excitement the other day about a Nature Physics paper proposing a way to search for quantum gravity not with a billion-dollar accelerator, but with a tabletop experiment. There's a write-up at Ars Technica, but that comes at it mostly from the quantum gravity side, which leaves room for a little Q&A from the quantum optics side. Wait a minute, you said this is in…
A little more tab clearance, here, this time a few recent stories dealing with those elusive little buggers, neutrinos. In roughly chronological order: The Daya Bay experiment in China has measured a key parameter for neutrino oscillation (arxiv paper), the phenomenon where neutrinos of one of the three observed types slowly evolve into one of the others. Mathematically, this is described as each of the three types we observe being an admixture of three more fundamental types. This mixing is described in terms of the sine of some "mixing angle," because physicists love geometry, and two of…
So, the news of the moment in high-energy physics is the latest results being reported from a conference in Europe. The major experimental collaborations are presenting their newest analyses, sifting through terabyte-size haystacks of data looking for the metaphorical needle that is the Higgs boson. And what are those results? It sort of depends on who you ask. Tommaso Dorigo points at the final data from the Tevatron and claims victory; Matt Strassler thinks the lack of evidence at the LHC is almost as important, though there is progress there in excluding some new regions. The net result is…
It's not a good week for me to be writing about anything remotely controversial, but if I want to keep my physics blogging license, I need to say something about the latest fast neutrino news. This has followed the usual trajectory of such stories, with the bonus farcical element of people who blasted the media for buying into the initial release seizing triumphantly on an initial rumor in the press that was garbled into incomprehensibility. With a little more time, it's become more clear how their result has become less clear, and the best place to look for a description of this is Matt…
Physics World has released its list of the top ten breakthroughs in physics for the year, and it doesn't include either fast neutrinos or the Higgs boson: The two physics stories that dominated the news in 2011 were questions rather than solid scientific results, namely "Do neutrinos travel faster than light?" and "Has the Higgs boson been found?". However, there have also been some fantastic bona fide research discoveries over the last 12 months, which made it difficult to decide on the Physics World 2011 Breakthrough of the Year. But after much debate among the Physics World editorial team…
I was planning to let today's Higgs press conference pass with only a few oblique mentions in posts about other things, but apparently, I would lose my license to blog about physics if I did that. You'd think that, being married to a lawyer, and all, I'd know to read the fine print in these things... Anyway, I don't really have anything useful to say about it. My very-much-an-outsider reading of this is that the evidence they see is suggestive, but somewhat less impressive than even the many attempts to lower expectations on Twitter and elsewhere suggested. It's probably there, but they're…
One of the many things I wish I had had time to blog about during the just-completed term was the big New York Times article on attrition in science majors. This generated enough commentary at the time that people are probably sick of it, but I haven't seen anything that exactly matches my take, so I'll belatedly throw this out there. The big point of the article is that lots of students who enter college planning to major in Science, Technology, Engineering or Math (the "STEM" fields, in an awkward but now inescapable acronym) end up graduating with degrees in something else: But, it turns…
One of the more reasonable criticisms of the OPERA result showing neutrinos apparently moving faster than light was that they were claiming 20-nanosecond resolution on the timing of a neutrino pulse that was 10000 nanoseconds long. They got their timing by doing fits to the shape of the whole pulse, as described in that link, and there's always a little bit of alchemy in that sort of process, but they had big long pulses because that's what the accelerator at CERN that served as the source of the neutrino beam provided. After the original annoucnement, they got the neutrino beam reconfigured…
I've been incredibly busy this term, but not so busy I couldn't create more work for myself. Specifically, by writing an opinion piece for Physics World about the FTL neutrino business, that just went live on their web site: The result quickly turned into one of the most covered physics stories of the year, with numerous articles in magazines, newspapers and on television asking whether "Einstein was wrong". Just as quickly came numerous physicists denouncing the media frenzy, with Lawrence Krauss from Arizona State University and Cambridge University cosmologist Martin Rees both calling the…
It's been a while since I posted anything science-y, and I've got some time between flipping pancakes, so here's an odd thing from the last few weeks of science news. Last week, there was an article in Nature about the wonders of string theory applied to condensed matter physics. This uses the "AdS/CFT" relationship, by which theorists can take a theory describing a bunch of strongly interacting particles in three dimensions (such as the electrons inside a solid), and describe it mathematically as a theory involving a black hole in four dimensions. This might seem like a strange thing to do,…
In a lot of ways, the OPERA fast-neutrino business has been less a story about science than a story about the perils of the new media landscape. We went through another stage of this a day or two ago, with all sorts of people Twittering, resharing, and repeating in other ways a story that the whole thing has been explained as a relativistic effect due to the motion of GPS satellites. So, relativity itself has overthrown an attack on relativity. Huzzah, Einstein! Right? Well, maybe. I'm not quite ready to call the story closed, though, for several reasons. First and foremost is the fact that…
The 2011 Nobel Prize in Physics goes to Saul Perlmutter, Brian P. Schmidt and Adam G. Riess "for the discovery of the accelerating expansion of the Universe through observations of distant supernovae." Ethan will presumably have a post with about a gigabyte worth of images in it shortly, or if you prefer your information in book form, you can read Richard Panek's The Four Percent Universe, which has lots of detail about what they did, including the rivalry between the different groups. As a bonus, the UK edition has a blurb from yours truly... But that's not what you really want to know--…
There have been a lot of pixels spilled over this faster-than-light neutrino business, so it might not seem like something I should take time away from pressing work to write up. It is the story of the moment, though, and too much of the commentary I've seen has been of the form "I am a {theorist, journalist} so hearing about experimental details gives me the vapors" (a snarky paraphrase, obviously). This suggests that there's still room for a canine-level write-up going into a bit more depth about what they did and where it might be wrong. So, what did those jokers at CERN pull this time?…
The final sentence of the neutrino paper that everybody is buzzing about: We deliberately do not attempt any theoretical or phenomenological interpretation of the results. From a somewhat older work in physics: Rationem vero harum gravitatis proprietatum ex phænomenis nondum potui deducere, et hypotheses non fingo. Quicquid enim ex phænomenis non deducitur, hypothesis vocanda est; et hypotheses seu metaphysicae, seu physicae, seu qualitatum occultarum, seu mechanicae, in philosophia experimentali locum non habent. In hac philosophia Propositiones deducuntur ex phaenomenis, et redduntur…
The final Space Shuttle landed the other day, leading to much lamentation over the end of the program, all over the Internet. It was absolutely choking my Twitter feeds for a while, which is mostly what I was thinking about when I re-tweeted this snide comment from Robert Lamb (though, to be fair, most of the people choking my Twitter feeds with Shuttle-related comments are space obsessives anyway, so it's not that new). I got a little grief for that over in locked LiveJournal land, so I thought I might as well say a bit more about it here. While there is some part of me that feels a little…
Among the articles highlighted in this week's Physics is one about a new test of QED through a measurement of the g-factor of the electron in silicon ions. This comes on the heels of a measurement of proton spin flips (this includes a free PDF) a couple of weeks ago, and those, in turn, build on measurements of electrons from a few years back, which Jerry Gabrielse talked about at DAMOP. Evidently, it's magnetic moment season in the world of physics. The media reports on the proton experiment tend to be a little garbled in a way that reveals the writers don't quite understand what's going on…
It's been a long and brutally busy week here, so I really ought to just take a day off from blogging. But there's a new paper in Science on quantum physics that's just too good to pass up, so here's a ReasearchBlogging post to close out the week. Aw, c'mon, dude, I'm tired. What's so cool about this paper that it can't wait until next week? Well, the title kind of says it all: they measured the average trajectories of single photons passing through a double-slit apparatus. By making lots of repeated weak measurements at different positions behind the slits, they could reconstruct the average…