New Higgs Results

Posted on November 13, 2012 by woit

New results about the Higgs should appear over the next day or so, perhaps first here and here. First to appear is the CMS tau-tau result which is a signal strength of .72 +/- .52 the SM value.

Will update this posting with the results as they appear.

I guess the rumors were right: no update from ATLAS for gamma-gamma, they’re just presenting the earlier data: signal strength of 1.8 +/- .5 times the SM value. “Ambitious campaign underway to include a larger data-set.”

ATLAS WW channel signal strength is 1.5 +/- .6 times the SM value (see here). For some reason they are only using 2012 8 TeV data, not combining with the 7 TeV data.

Atlas tau-tau signal strength is .7 +/- .64 times the SM value (see here). Very similar to the CMS value. They are not yet sensitive to the bb channel, where the Tevatron has the advantage and has evidence of a signal.

Update: All new results are out now, but rather anti-climactic since neither CMS nor ATLAS is reporting new results for the channel with the strongest signal (gamma-gamma), where the signal strength may be anomalously high. ATLAS is also not reporting for the other high statistics channel (ZZ). CMS is, with signal strength .8 +.35/-.28 the SM value. They also claim to rule out (at 2.5 sigma) the hypothesis that this is a pseudoscalar rather than scalar. Everything reported is in line with the SM, but for the most interesting numbers we may have to wait until next March (Moriond).

For much more details about all this, see Tommaso Dorigo here and here, Matt Strassler here and here, Philip Gibbs here. For primary sources, CMS here, ATLAS here, presentations here.

Update: For another excellent source, see Jester, who has the scoop on why ATLAS and CMS didn’t update some channels:

It came to a point where the most exciting thing about the new Higgs release was what wasn’t there šŸ™‚ It is difficult not to notice that the easy Higgs search channels, hā†’Ī³Ī³ and ATLAS hā†’ZZā†’4l, were not updated. In ATLAS, the reason was the discrepancy between the Higgs masses measured in those 2 channels: the best fit mass came out 123.5 GeV in the hā†’ZZā†’4l, and 126.5 GeV in the hā†’Ī³Ī³ channel. The difference is larger than the estimated mass resolution, therefore ATLAS decided to postpone the update in order to carefully investigate the problem. On the other hand in CMS, after unblinding the new analysis in the hā†’Ī³Ī³ channel, the signal strength went down by more than they were comfortable with; in particular the new results are not very consistent with what was presented on the 4th of July. Most likely, all these analyses will be released before the end of the year, after more cross-checking is done.

Update: Two interesting workshops on prospects for a Higgs factory are being held at Fermilab this week. See here for one that is on-going, see here for Tuesday’s one-day mini-workshop on prospects for a muon collider Higgs factory. I’d never seen much before about the idea of using a gamma-gamma collider to study the Higgs, curious if that’s really technologically viable.

Posted in Experimental HEP News | 20 Comments

SUSY in the Hospital?

Posted on November 13, 2012 by woit

HCP2012 Higgs results will be announced Wednesday (I’m hearing that CMS tau-tau signal is .7 +/- .5 x the SM value), but interest may focus much more on the strong SUSY exclusions being announced there. So far the LHCb result on B(s)->mu+mu- has been the one getting all the attention, with a BBC News story describing it as “a significant blow to the theory of physics known as supersymmetry”. In the story experimentalist Chris Parkes describes the current situation as “Supersymmetry may not be dead but these latest results have certainly put it into hospital.” John Ellis is having none of this though:

Supporters of supersymmetry, however, such as Prof John Ellis of King’s College London said that the observation is “quite consistent with supersymmetry”.

“In fact,” he said “(it) was actually expected in (some) supersymmetric models. I certainly won’t lose any sleep over the result.”

The story has been picked up by Slashdot, and the Register (which has Supersymmetry takes an arrow to the knee).

The bad news for SUSY out of Kyoto however does not end there. ATLAS and CMS are both coming out with new analyses using this year’s 8 TeV data which significantly expand previous limits on SUSY, getting close to ruling out popular last-ditch efforts to save the theory. For the latest, look at this HCP2012 page, this ongoing Chicago workshop, and CMS results announced here (like this), ATLAS results announced here.

The last ditch effort to save the idea that SUSY solves the so-called hierarchy problem goes under the name of “Natural Supersymmetry”. It involves moving most superpartners to high masses where the LHC can’t see them, keeping only the stop, sbottom, gluinos, and a couple neutralinos at LHC accessible masses. If you look at the bounds given on these masses for instance here, and compare to the latest LHC results, you’ll see that there’s trouble on all fronts for this idea, which is now very close to being essentially ruled out.

Gordon Kane is fighting back against the BBC by going to Lubos Motl’s blog to argue that the LHCb result is no problem for his string theory “predictions”. You see, his “prediction” is now that most superpartners are way beyond what the LHC can see, so not only is the LHCb result not negative for SUSY, but it “adds to the evidence for supersymmetry and for M/string theories”. Kane doesn’t mention any of the other SUSY excluding results coming out this week, or their implications for his “prediction” of the gluino mass. Last year Kane was telling Tommaso Dorigo

I and others expect this decay to tops and bottoms is the signature by which gluinos will be found, with masses well below a TeV

and his slides had a gluino mass prediction of about 600 GeV. Late last year he was arguing that the gluinos would be seen by this past summer. More recently, he’s modified the graph in his slides to move the gluino up to 1 TeV. This week ATLAS reports a new gluino mass limit of 1.24 TeV, so Kane will have to modify his slides yet again.

The combined effect of the bad press and the devastating experimental results on the 30 year old SUSY juggernaut will be interesting to follow. At this point, it is hard to see how one could rationally expect anything positive for SUSY to come out of further analyses of the 7 TeV and 8 TeV data. I suppose many will try and delay acknowledging failure by saying one must wait for the 13 TeV data, which we won’t see until 2015 or so, but I don’t think this is going to convince many people.

Update: Matt Strassler objects to the BBC article, on the grounds that one should not describe what is happening to SUSY in terms of “blows” or it getting hurt. Instead, one should stick to saying it is getting “cornered”, and he agrees that “the cornering of supersymmetry is well underway”. The question this raises though is what happens to SUSY once it is cornered if you object to it getting hurt. I suspect the hope of many SUSY theorists is that even once cornered, SUSY will continue to be well-treated, receiving annual $3 million prizes and being taught to new generations of graduate students.

Update: The Daily Mail covers this, with the non-tabloid-like headline Experts take conflicting opinions as to how far results support the theory of super symmetry. Oliver Buchmueller joins Gordon Kane in the bizarre game of claiming negative results as positive for SUSY, making the argument

‘This is another piece in the puzzle and with it the world appears even more SM-like,’ he said. ‘It supports SUSY, because that is the only theory that can include the Standard Model in a wider concept of New Physics.’

Update: More about this from Matt Strassler, who writes about Theory Killers at the HCP conference. I guess it’s still all right to kill “theories”, as long as SUSY herself doesn’t get hurt.

Update: The rather odd controversy over the BBC story goes on, with Lubos Motl and Matt Strassler continuing to argue that the scientific method implies that SUSY can’t get hurt. I would have thought that it was uncontroversial that if proponents of an idea claimed that it would be vindicated by an experiment, and the experimental result came back negative, that was not good for the idea, but, at least for SUSY, that doesn’t seem to be the case. Yes, SUSY comes in infinite varieties, many of them never testable, but the experimental results shooting down its versions sold as the most well-motivated ones do have implications for its health. I see no reason why one needs to wait for the LHC to examine every possible remote corner of parameter space that it can access before remarking on what has happened.

Update: It is being pointed out that the BBC story is inaccurate: the LHCb bounds on Bs meson decays that rule out a large chunk of SUSY theory space were already there in March. So, on this front SUSY entered the hospital in March, not this past week. Of course, an even bigger inaccuracy in the BBC story was describing SUSY as an idea that has only encountered serious health problems recently, rather than many years ago…

Update: There’s now a fourth rant from Matt Strassler about the LHCb result, a topic on which he has become a bit of a zealot. The point being made is that SUSY was already so badly injured pre-LHCb that they didn’t make things any worse. It’s quite possible he’s right about this, would be interesting to hear a response from the LHCb people.

Update: A characteristically lucid posting on the topic from Jester: BS and SUSY.

To conclude, you should interpret the LHCb measurement of the Bsā†’Ī¼Ī¼ branching fraction as a general, strong bound on theories on new physics coupled to leptons and, in a flavor violating way, to quarks. In the context of SUSY, however, there are far better reasons to believe her dead (flavor, CP, hierarchy problem, direct searches). So one should not view Bsā†’Ī¼Ī¼ as the SUSY killer, but as just another handful of earth upon the coffin šŸ˜‰

Posted in Experimental HEP News | 52 Comments

HCP2012

Posted on November 9, 2012 by woit

The Hadron Collider Physics Symposium will be next week in Kyoto, with announcements of new results from the LHC, some details of which are starting to trickle in. Chris Quigg explains what to look for here.

The LHC has just recently passed the milestone of 20 fb-1 of data at 8 TeV this year. Perhaps this will get up to 25 fb-1 by the end of this run later this year. After a heavy ion run early next year the machine will go into a long shutdown (until late 2014) for repairs to allow operation at close to design energy (probably at 13 TeV). Next week results will be reported based on 12 fb-1 (CMS) and 13 fb-1 (ATLAS) of this year’s 8 TeV data (compare to this past summer’s results based on 5.3 fb-1 (CMS) and 5.9 fb-1 (ATLAS)). Expect results from the full 2012 data at Moriond in March, with an official combination of results from the two experiments next summer.

On Monday LHCb will report the latest results on B(s)->mu+mu-, and the latest Higgs news should come at the Higgs parallel session on Wednesday. There will also be quite a few new, stronger limits on SUSY.

I’m hearing that these new results already can rule out the idea that this new particle is a pseudo-scalar. There will be no confirmation of an unexpectedly high gamma-gamma rate. Some excesses in the tau-tau channel are being seen, of roughly the size you would expect for a SM Higgs. So, all in all, things are still consistent with a SM Higgs. If not, please let me know….

Update: The B(s)->mu+mu- results from LHCb are out (see here), providing good agreement with the SM, and new, strong limits on possible SUSY models (see the last slide). More from Matt Strassler and Michael Schmitt.

For another source for new LHC results, together with interpretation of their signficance, the Chicago 2012 Workshop on LHC Physics is starting today.

Posted in Experimental HEP News | 26 Comments

A Lost Generation?

Posted on November 4, 2012 by woit

I’m in Northern California, on a vacation originally intended to be short, but started early due to the storm in New York. I wanted though to recommend reading something that a commenter here pointed to. It’s an article by Mikhail Shifman (author by the way, of an excellent recent textbook I somehow haven’t found time to discuss here) about the current state of particle theory that he has just posted on the arXiv, with the title Reflections and Impressionistic Portrait at the Conference “Frontiers Beyond the Standard Model,” FTPI, Oct. 2012. The reference is to this recent conference, held at his institution.

Shifman surveys the current state of particle theory, with a range of interesting comments about the paradigms of grand unification, extra dimensions, supersymmetry and string theory that have dominated the subject for nearly 30 years. The negative LHC results provide a serious challenge to these paradigms, although I’d argue that they have been in trouble for a very long time, with the LHC just the final nail in the coffin. Much of the activity among theorists reported at the conference referred to by Shifman revolves around attempts to prop up some of these ideas. This is going to be increasingly unsustainable as stronger and stronger LHC bounds emerge. Where will this leave the field? Shifman argues that this is a time of opportunity, with the death of old paradigms opening the way for new ideas. I hope he’s right. Here are his final comments, of a sociological nature:

It is easy to estimate the total number of active high-energy theorists. Every day hep-th and hep-ph bring us about thirty new papers. Assuming that on average an active theorist publishes 3-4 papers per year, we get 2500 to 3000 theorists. The majority of them are young theorists in their thirties or early forties. During their careers many of them never worked on any issues beyond supersymmetry-based phenomenology or string theory. Given the crises (or, at least, huge question marks) in these two areas we currently face, there seems to be a serious problem in the community. Usually such times of uncertainty as to the direction of future research offer wide opportunities to young people, in the prime of their careers. To grab these opportunities a certain reorientation and reeducation are apparently needed. Will this happen?

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Latest Links

Posted on October 26, 2012 by woit
  • On the LHC front, new results will be announced at the Hadron Collider Physics Symposium in Kyoto, which opens November 12. Jester has a good summary of what to look for on the Higgs front here. The new results should be based on about 12-13 fb-1 of 2012 8 TeV data (this past summer’s used about 5 fb-1 each of 2011 7 TeV data and 2012 8 TeV data). Unblinding of the results should have taken place recently, so soon about 6000 physicists will know what the news is and start talking about it…
  • The latest Scientific American has a cover story about particle physics that comes under the “This Week’s Hype” heading. It’s called “The Inner Life of Quarks” and discusses models in which quarks and other elementary particles of the standard model are composites of more elementary objects called “preons”. The fact that the papers on the subject it refers to are from 1979 should make one suspicious: an idea that hasn’t had major developments in 33 years is a dead idea. Besides the overwhelming experimental evidence against preons (with the LHC bringing in many new much stronger negative results), the idea has huge inherent problems. The main issue is that one is trying to put together composites with masses as small as MeVs (or lower, if you try to do this with neutrinos) while the data says that things are point-like up to TeV scales, with just the forces you know about up to such scales.
  • For the latest on Paul Frampton’s troubles as the victim of a scam that has left him in an Argentine jail, see this article entitled Imprisoned UNC professor thinks he deserves a raise. I’m assuming this was before his trip to South America, but at some point Frampton clearly did some extensive research, comparing his salary ($107K) to those of some of his illustrious peers ($203K-$532K according to him, just using data from public universities). Not clear though that this was really something to bring up in his argument about whether the university should still pay him even if he’s in jail.
  • I only recently heard the old news that Fields Medalist Vaughan Jones has left Berkeley to take a job at Vanderbilt University. Evidently one reason for doing this was a salary number of the sort that Frampton covets.
  • Freeman Dyson has a piece in the New York Review of Books about Jim Holt’s new book Why Does the World Exist (see my take here). Not much in the review actually about Holt’s book, but Dyson takes the opportunity to enter the ring in the fight over nothingness with some late blows aimed at the philosophers. He doesn’t think much of modern philosophy, ending with:

    The great philosophers of the past wrote literary masterpieces such as the Book of Job and the Confessions of Saint Augustine. The latest masterpieces written by a philosopher were probably Friedrich Nietzscheā€™s Thus Spoke Zarathustra in 1885 and Beyond Good and Evil in 1886. Modern departments of philosophy have no place for the mystical.

    There’s a Chronicle of Higher Education piece about this here, Brian Leiter’s blog hosts a discussion here.

  • I’m loathe to post anything about US politics here, since it’s a depressing and omnipresent topic these days, but for an HEP angle, see this in Science from Adrian Cho, and this in the NYRB from Steven Weinberg. Don’t even think though of posting comments about politics here…
  • Greg Moore recently gave the Felix Klein lectures in Bonn on Applications of the six-dimensional (2,0) theory to physical mathematics . Video here, lecture notes here.
  • This week at Stony Brook there’s a conference in honor of Blaine Lawson’s 70th birthday. Lawson is a great person and a wonderful geometer; I very much enjoyed getting to know him a little bit during my days as a physics postdoc at Stony Brook. He was one of several examples that convinced me that leaving physics for mathematics would at least promise hanging out with nicer people. I’ve been too busy this week to get out to Stony Brook, had formed a crazy plan to bike out there this weekend for Nigel Hitchin’s talk Sunday morning, but a nasty cold has put an end to that plan (Sunday’s weather prediction for an approaching hurricane might in any case have made a long bike trip not the best idea in the world). Videos of the talks are available here.

    Happy Birthday Blaine!

Posted in Uncategorized | 32 Comments

Why Author Pays Open Access is a Bad Idea

Posted on October 20, 2012 by woit

There’s a wonderful piece of software out there I hadn’t heard about, called Mathgen, which generates impressive looking mathematics research papers that are utter gobbledygook. A Mathgen paper on Independent, Negative, Canonically Turing Arrows of Equations and Problems in Applied Formal PDE was recently accepted (see the full story here) by the journal Advances in Pure Mathematics, one of many “open access” journals put out by Scientific Research Publishing. If you’re looking for theoretical physics papers instead of pure math, Scientific Research Publishing has the Journal of Modern Physics. Some work on Mathgen is probably required before it is ready to submit papers to this journal.

These journals charge authors $500 to publish their papers, something which is now being sold as a wonderful mechanism for providing “open access” to the scientific literature. At the same time they make very clear what one big problem with this is: the financial incentive for the journal becomes to publish as many papers as possible, since that’s the only way to increase revenue. Scientific Research Publishing does a good job of showing where this model for funding dissemination of academic research leads.

Posted in Uncategorized | 50 Comments

Fields Medal Symposium

Posted on October 19, 2012 by woit

I just got back from a few days in Toronto, where I attended the Fields Medal Symposium on Fundamentals of the Langlands Program. This is the first of a planned yearly series to be held a the Fields Institute, with the idea that each Symposium will focus on an area of mathematics crucial to the work of one of the recent Fields medalists. In this one, Ngô and his work proving the Fundamental Lemma in Langlands theory was the center of attention.

The talks were recorded, and I believe that video of them will soon appear. An effort was made to get speakers to give talks aimed at non-specialists, and the results were quite good. Among the talks I attended, I can highly recommend those of Sophie Morel, Edward Frenkel, Nigel Hitchin and Edward Witten, which covered some of the huge diversity of fundamental mathematics that goes into this subject. Unfortunately I only got to Toronto midday Tuesday, so missed all the Monday and Tuesday morning talks. I heard that the Tuesday morning talks of Richard Taylor and Michael Harris gave excellent introductory surveys on the number-theory Langlands program. Monday was devoted to more specialized talks on endoscopy and the fundamental lemma.

Ngô’s talk was about some new ideas on how to go “Beyond Endoscopy”, to extend previously successful uses of the trace formula to prove Langlands functoriality to a wider range of examples than those covered by the fundamental lemma. Another example of this sort of ongoing work mentioned by a couple speakers was work by Ali Altug, who has just finished up as a student at Princeton and started teaching here at Columbia this fall. Witten’s talk surveyed the relationship between QFT and geometric Langlands, motivating clearly why the N=4, d=4 SYM theory appears. For more details about much of the more advanced material covered in his talk, see the write-up here of his lecture at Atiyah’s 80th birthday conference.

Monday evening there was a big evening program for the public (which I watched some of from New York via web-cast), and Tuesday evening there was a special program for high school and college students, with Ingrid Daubechies and Frenkel giving talks, as well as a panel discussion with them, Ngô and James Stewart. A lot of students attended, and many stayed on for almost an hour to talk with the speakers. Ngô has a popular book out in Vietnam, which evidently has been a huge success. Frenkel has a book entitled Love and Math coming out next year, a chapter of it is available here.

Panelist Jim Stewart has them both beaten as a successful author. His excellent Calculus textbook may be the most widely-used one in the US, and evidently the financial rewards have been significant. He was one of the financial supporters of the symposium, and Wednesday night had many participants out to his amazing home in Rosedale for a banquet. It’s a spectacular, award-winning piece of architecture he calls “Integral House”, and its five stories and 18,000 square feet of space are perched over a ravine not far from downtown Toronto. Evidently it cost him about $24 million, as well as about ten years of his life in design and execution. For more about Stewart and Integral House, see here, here, and here.

Richard Cerezo was taking lots of pictures and has been posting on the Symposium blog here. A short video of me, Frenkel and Hitchin discussing the Symposium topic may appear there at some point.

Update: The conversation with Frenkel and Hitchin is now available here.

Posted in Langlands | 14 Comments

Templeton Funds Physics of Information

Posted on October 19, 2012 by woit

FQXi has recently issued a Request for Proposals, using money from the Templeton Foundation to fund about $3 million in grants for research on the “Physics of Information”:

  • What is the relationship between information and reality? Can information exist without any ā€œmaterialā€ substance? Can matter exist without any information? Or, are information and reality two sides of the same coin?
  • How does nature (the universe and things therein) process information? Are there fundamental limits? How is nature shaped and transformed by processing information?
  • What are the fundamental differences between classical and quantum information?
  • What can the physics of information reveal about black holes, singularities, physics at the Planck length, and the origins and fate of our universe?

This follows on the heels of $4 million in grants announced last week on the topic of New Frontiers in Astronomy and Cosmology.

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Yet More Links

Posted on October 14, 2012 by woit
  • From commenter Clark here, news that Mochizuki has acknowledged that the problem pointed out by Vesselin Dmitrov with his proof of the abc conjecture on MathOverflow is a real one, but claims that the argument can be fixed, with fixes that he explains here. He is preparing updated versions of the papers containing flaws.
  • As new negative results about SUSY keep coming in, Nanopoulos et al. issue new “predictions” of a SUSY signal just around the corner. In light of this from ATLAS, here’s an updated list of “best fits” for SUSY (first posted here)

    arXiv:1007.5100 455 GeV (“Golden Point”)
    arXiv:1009.2981 455-481 GeV (“Golden Strip”)
    arXiv:1111.0236 512 GeV (“Universe F-U2”)
    arXiv:1111.4204 518 GeV (“Profumo di SUSY”)
    arXiv:1203.1918 610 GeV (“Aroma of Stops and Gluinos”)
    arXiv:1205.3052 708 GeV (“The Sweet Fragrance of SUSY”)
    arXiv:1210.3011 756 GeV (“Primordial Synthesis”)

    The authors have stopped going on about how this all smells, but now are acknowledging help from Tommaso Dorigo (see here).

  • Tomorrow at Boston University there will be a conference on quantum gravity, celebrating the 40th Anniversary of the First Osgood Hill Conference on Quantum Gravity.
  • The Higgs continues to get lots of positive media attention. This week’s episode of The Big Bang Theory was called The Higgs Boson Observation, and features lots of Higgs-related things on the blackboards.

    At the IAS in Princeton, Yuri Milner’s multi-million-dollar men are giving public talks about the Higgs. Last week was Juan Maldacena on The Symmetry and Simplicity of the Laws of Nature and the Higgs Boson, next week it will be Nima Arkani-Hamed on The Inevitability of Physical Laws: Why the Higgs Has to Exist. At some point these talks may appear here.

  • On Friday the Templeton Foundation handed out $5.6 million as part of its New Frontiers in Astronomy and Cosmology competition, some to students for writing essays, most of it to physicists and astronomers, many of whom promise to find ways of testing the Multiverse (grant winners are here). Intriguingly, David Spergel is not just “testing” the Multiverse, but “detecting or falsifying” it, I wonder what that’s about.
  • Lots of self-examination going on in the US HEP community about what to do post-Higgs discovery. Argonne had an HEP Higgs Retreat (no slides for “SUSY is Dead?” it seems). The past few days at Fermilab there was a DPF Community Planning Meeting, organizing activities to lead up to next summer’s “Snowmass” Community Study, to be held in Minneapolis. What’s long overdue but unlikely to happen would be a US Community Study of the implications of the SUSY/string theory fiasco for HEP theory.
  • The Calculus of Love is a short film with a math theme involving the Goldbach conjecture.
  • For a debate about Pythagoreanism, the idea that math is the key to the universe, see here. An interesting debate, but maybe they should have had some mathematicians involved…
  • Last week I was up in Boston and went to some of the talks at a conference in honor of Daniel Quillen, who passed away last year. Quillen’s remarkable and influential work was at the boundary of topology and algebra, in particular he was largely responsible for discovering how to properly define algebraic K-theory. An early version was distributed of material about Quillen that will appear in the November Notices of the AMS, including a long explanation by Graeme Segal of the high points of Quillen’s mathematical contributions (Note added: this is now available here). I found the talks by Segal and Hopkins both inspiring and baffling, with Hopkins in particular starting off slow and comprehensible, but reaching escape velocity by the time he got around to what sounds like an exciting new result about the Brauer group in the context of stable homotopy theory. This is joint work with Lurie and Lieblich, but you’re going to have to find someone other than me to explain it to you.
    This coming week I’ll be in Toronto for the Fields Medal Symposium, which will cover all things Langlands. The opening public lectures will be live-cast, see here.
Posted in Uncategorized | 6 Comments

Post-discovery Higgs Books

Posted on October 11, 2012 by woit

The Higgs particle has been the main player in various popular books about particle physics since before many of today’s college students were born, with Lederman and Teresi’s The God Particle going back to 1993. Last year’s excellent The Infinity Puzzle by Frank Close (discussed here) was largely about the Higgs story, appearing just before the first experimental indications of the Higgs late last year.

I’m not the only one who was obsessively following the Higgs discovery story as it unfolded from last year until the final announcements this past July 4. Two of the others have already produced books on the topic: Jim Baggott’s Higgs: The Invention and Discovery of the ‘God Particle’ came out last month, Sean Carroll’s The Particle at the End of the Universe: How the Hunt for the Higgs Boson Leads Us to the Edge of a New World, will be in stores next month.

I’ve just finished reading copies of both of them, and they’re both very good. They each cover the story of the Standard Model well, supplemented by extensive discussion of the Higgs discovery at the LHC and the background of how it came about. I confess that it’s a bit eerie to see a lot of things that were day-to-day news and often grist for the blog now packaged between hard-covers as history, while I’m also happy to see that a good job is being done of it.

Baggott’s book is quite a bit shorter, and has much more of a linear structure, taking the reader historically through the development of the Standard Model and its experimental tests, up through the LHC and the work of CMS and ATLAS that led to the Higgs discovery. You also get as a bonus a wonderful foreword by Steven Weinberg who, among other things, explains why quarks were not in his 1967 paper (he didn’t believe in them). If you want the quickest possible journey through this material, definitely choose this one.

Carroll’s effort is much longer, more non-linear and digressive. You get a significantly more in-depth version of parts of this story, with an organization that starts with the discovery and works outwards, explaining various topics needed to understand what this is all about, rather than following the line of historical development. I’m not really a good person to judge how this will work for those approaching this subject without a lot of background, but it seems to be as good a way as any to get readers into the subject. Among the topics Carroll has the space to cover in depth, he does a very good job with the history of the Higgs mechanism and the various claims to have done something Nobel-worthy, including the crucial role of Philip Anderson that often gets overlooked.

Since I’m known for my negativity, I’ll add a few criticisms here of these otherwise excellent books. Baggott goes with the “God Particle” business in his subtitle, presumably for the same excellent reason that Lederman used it: anything with “God” in it sells more books. One of Carroll’s digressions is about the “God Particle” business (he’s strongly against it and God in general) but his “Particle at the End of the Universe” replacement doesn’t seem to me to be much of an improvement. His subtitle and some of the jacket copy (“a doorway is opening into the extraordinary: the mind-boggling world of dark matter and beyond”) oversells a topic he wisely devotes no more than a couple pages to in the text of the book, so-called “Higgs portal” models of dark matter.

Both authors write fairly extensively about the role played by bloggers in spreading news and rumors during this recent period, and I make an appearance in both books. This caused me to go back and recall some of the details of how this played out. Both Baggott and Carroll describe how the abstract of an internal ATLAS note was anonymously posted on my blog (see here). Carroll’s version is slightly inaccurate, implying the entire memo was posted there, while it was only the abstract. The full note was sent to me privately by people who wanted me to have a better idea of what was going on, but I did not post that on the blog, and reading the full note made it pretty clear that while this wasn’t a hoax, it also wasn’t worth taking seriously. My impression is that the outraged reaction from various people at ATLAS to this leak was equal parts justifiable concern about keeping this kind of material confidential, and embarrassment about something this dubious seeing the light of day with the name of their collaboration on it. The unfolding of this story gave me a lot to think about, and I ended up deciding that I was definitely not comfortable being a public source of actual confidential documents, while at the same time seeing nothing wrong with providing accurate summary accounts of what the 3000 people in one of these large collaborations were all aware of and discussing. I offered to ATLAS people to remove the abstract if they asked me to, they decided it was best not to do this.

The first solid evidence for the Higgs that I heard about was in late November 2011 (see here and here), with a comment giving the right mass appearing at viXra log convincing me that the time had come to go public with some details. What was remarkable about this evidence was not that something was being seen at the 2-3 sigma level, but that both experiments were seeing something at almost the same mass value. This immediately convinced me that this was likely to be a Higgs signal, and the further details that came out over the next days up to the public announcement December 13 made for a rather strong case that the Higgs had been found.

In some sense the news this past summer was anti-climactic, just confirming that the strong 2011 evidence was the real thing. In early June news came from ATLAS that they were seeing the same gamma-gamma signal as in the 2011 data, just before I left for vacation (see here). When I got back from vacation, a lot more details showed that both experiments definitely had the thing in the bag. My posting about this got a lot of attention, including a link from the New York Times (where Dennis Overbye reported that Fabiola Gianotti of ATLAS was telling him “Please do not believe the blogs”).

All in all, I’m fairly happy with my decisions about what to write and what not to write on the blog about not-quite-public results about the Higgs. There’s been a certain amount of criticism about the terrible violations of confidentiality involved, but I can’t help pointing out that the things I was writing about were at the time known to the majority of the HEP community: the 6000 physicists on ATLAS and CMS. Carroll has this to to report about the confidentiality question:

I asked one physicist whether the results that ATLAS was getting were generally known within CMS, and vice versa. “Are you kidding?” I was told with a laugh. “Half of ATLAS is sleeping with half of CMS. Of course they know!”

For that quote, and many other stories worth reading about, if you’re the sort who loves popular books about particle physics, both of these are worth buying. If you’re only moderately interested, just pick one of the two and read it, you can’t go wrong…

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