The book has been described here before, so I will not do it again. At the above link you can find a description and the index of the book, along with endorsements by Edward Witten, Gordon Kane, Peter Woit, Gianfrancesco Giudice, and Sean Carroll.Here I will offer you a clip from a chapter titled "Preon Dreams", where is described the media storm that hit the CDF collaboration in 1996, following the publication of a controversial measurement of jet cross sections. The measurement showed a departure from the predictions of quantum chromodynamics for very high-energy jets, which was suggestive of the effect of a sub-structure in quarks and gluons, when probed by very high-energy collisions. This is in analogy with Rutherford's experiment, where atomic nuclei showed their existence by causing large deflections in a beam of alpha particles.
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In the course of January 1996, Science magazine conducted several interviews and collected material for a publication of the story. The Science reporter was James Glanz, who had a Ph.D. in astrophysics: this was close to the best possible scenario that CDF could hope for, as the article was guaranteed to contain neither sensationalistic claims nor incorrect or deceiving statements. And indeed it did not. However, Science had a policy of "leaking out" to local newspapers the most interesting articles they were about to publish, just before the magazine got distributed. And there was the rub. Would local newspapers match the high standards of the flawless text produced by Glanz? Not a chance.
On the February 9th 1996 issue of Science, James Glanz titles open-mindedly: "Collisions Hint That Quarks Might Not Be Indivisible." His article is quite good and balanced, and it explains the physics well, without making unsupported claims. The article also contains several quotes from CDF members, starting from the spokespersons:
This is just the sort of effect you would see" says CDF-co-spokesperson William Carithers, "if quarks were not fundamental particles but had some sort of internal structure.
And then Giorgio Bellettini:
As these events began to accumulate [...] "a fierce fight" broke out within the collaboration over how to gauge the small chance that systematic experimental errors could explain the results. The researchers made exhaustive tests of the possibility that a "conspiracy" of random or systematic errors might be fooling them [...]. Finally, he says, the collaboration reached a consensus that the excess had to be real.
The article closes with a quote from Steve Geer, the other co-convener of the QCD group, who suggests what would only later be accepted as the correct solution:
Steve Geer, a CDF team member at Fermilab, describes the most dramatic possibility: "It might mean that, just as in Rutherford's atom, there's a hard center" lurking inside the quarks, as some speculative theories suggest. But Geer points out that several other explanations might account for the measurements. The more mundane possibility, he says, has to do with how momentum is parceled out among the components of a speeding proton. The hardest collisions occur when two quarks that happen to carry a high fraction of each proton's momentum meet head-on. But the mass-less gluons can carry momentum as well. So if, say, QCD underestimates how often gluons carry a high fraction of the momentum, then the quarks they encounter could suffer an unexpected number of violent collisions, and "we could end up with more energetic jets than expected."
Overall the Science article does not appear to be damaging to the CDF collaboration: no strong claims, only a report of work in progress. But in 1996 an influential minority of the CDF members was uneasy with any sort of media coverage of their work. A few of them were quite frightened that the lack of control over what could be perceived from the outside might damage their reputation, and worsen their chances of getting money and grants from the funding agencies. That paranoid feeling had its origin in a piece that Malcolm Browne had published on the New York Times on January 5th 1993, just months before the Superconducting Supercollider project was canceled by the US congress. The article titled "315 Physicists Report Failure in Search for Supersymmetry," and was built around the rather unremarkable news that a publication had been sent by CDF to Physical Review Letters to report lower mass limits in a search for squarks and gluinos. Browne had insisted on reporting the point of view of critics of "big science." To let you taste the flavor of the piece here are a few clips:
[...] despite this arsenal of brains and technological brawn assembled at the Fermilab accelerator laboratory, the participants have failed to find their quarry, a disagreeable reminder that as science gets harder, even Herculean efforts do not guarantee success." [...] "Some regard such failures as proof that high-energy physics, one of the biggest avenues of big science, is fast approaching a dead end." [...] "Failed experiments of such a grandiose scale offer easy marks to critics who contend that "big science" produces too meager a crop of knowledge for what it costs." [...] "all these projects soak up more human talent and more public money than society should permit, skeptics argue.
To his credit, Browne concluded the article with a nice quote by Wolfgang Panofsky, the director-emeritus of the SLAC laboratories:
If certain answers crucial to man's understanding of nature can be obtained only by large effort, is that sufficient reason for not seeking such answers?But that was not nearly enough. The potential danger of similar press coverage was well understood by some CDF members, who remembered vividly how just a few months after the Browne article the US Congress had cut the funding to the project of building a Superconducting Super Collider (SSC) in Waco, Texas. That was a hadron collider meant to reach the energy of 40 TeV with proton-proton collisions. The demise of the SSC was a bad blow to the US plan of research in frontier particle physics, and it shattered the hopes of many who had worked hard to design the detector and study the physics potential of the facility.
Of all the quotes in Glanz's article reported above, the one by Bellettini was badly received by some collaborators. It spoke of fights within the collaboration, and of a "real effect"; and it came from a spokesperson, which was an aggravating clause. Worse still, as the Science paper hit the press Bellettini was also featured in a National Broadcast Radio interview, where he explained the matter in his usually colorful, enthusiastic way. Bellettini has always been a true enthusiast of particle physics research: his verve and his passion have always fascinated his students, captivating them with his love of particle physics. I personally regard this as a great gift in a scientist, and I admire him for that; I cannot understand those who criticize him for his positive, energetic, inspiring attitude. In the radio interview, Bellettini gave a remarkable answer when asked what he believed was the source of the CDF anomaly: "Sometimes as I wake up in the morning I think it's new physics, and other times I wake up and think it is just QCD."
Bellettini's interview did not go unnoticed. The perception of the listeners to the NPR interview was that CDF had really found new physics. The phones of many CDF members started ringing that morning, with colleagues from other experiments calling to inquire on what that new find was: a new quark? An even tinier particle? A few of them were caught totally unprepared by the inquiries, as in a large collaboration with many different working groups even a striking result as the anomalous excess at large jet energy could get overlooked.
As mentioned above, several newspapers throughout the US managed to organize quick articles on the CDF anomaly as they got notified by Science. Many of those pieces appeared on February 8th. On the New York Times it was Malcolm Browne again, titling "Tiniest Nuclear Building Block May Not Be the Quark." Browne had got a hold of Brenna, and quoted her:
""What's different about these results," Dr. Flaugher said, "is that there are many more high-energy transverse jets than theory predicts. The highest energy transverse jets were 120 percent more frequent than theory would explain," she said."Brenna could not have possibly said "high-energy transverse jets" in place of the correct "high-transverse-energy jets"; but the quote was otherwise technically accurate. Another source identified by Browne as "a spokesperson," and which most in CDF would bet was Bellettini, was also quoted as saying "We spent more than a year working on the data to be reasonably sure we weren't making some big error, [...] and now we"re confident at least that something unexpected has happened." Again, not a terrible tweaking of facts, yet the mention of the "unexpected" was enough to disturb the most sensitive collaborators. On one thing the writer fully showed he had a clear vision, though, as he concluded his piece with the following forecast: "the C.D.F. paper is expected to undergo intensive scrutiny and criticism in the months ahead."
Curt Suplee on the same day wrote for the Washington Post a piece titled "Quark as Basic Particle May Be in Dispute." The quotes contained in his article did not have names attached, and the tone was open-minded:
It is possible that quarks -the smallest known constituents of protons and neutrons -are not fundamental, indivisible particles, but may be made up of yet smaller entities of unknown nature, said researchers from the Collider Detector at Fermilab" [...] "Until alternative explanations or possible errors have been ruled out, the 450-member team reports in a paper submitted to the nation's leading physics journal, Physical Review Letters, any claim about the presence or absence of new physics is not defensible.In this case what was most disturbing to CDF collaborators was the rather imprecise description of the findings of the experiment: one read that
The team turned up nearly 1,200 observations during a year of experiments in which colliding particles were deflected or "scattered" in ways that apparently cannot be reconciled with the predictions of current particle-physics theory. But the odd trajectories and energy levels observed in the collisions might make sense if quarks were composed of tiny sub-units that could send matter flying off in unexpected ways.
The above description was frankly sub-par, even for a national newspaper more accustomed to deal with politics and Football than with particle collisions. It is surprising to note that its author is a renowned and appreciated science writer, who has won during his career several awards for outreach activities. "Odd trajectories" and "matter flying off in unexpected ways" are rather awkward misrepresentations. They offer a good example of the dangers of oversimplification in outreach. Also, the mention of "1200 observations" must have been the result of a complete misunderstanding of the way the experiment collected its data; one which I cannot even trace back to a possible source. 1200 runs? 1200 events above 200 GeV? We will never know, but surely Suplee's article had its share of responsibility for the discontent among CDF members.
The Chicago Tribune also published on February 8th an article on the CDF anomaly, titled "Fermilab's `Preons": Bad Math Or A Profound Find? As Basic Matter, Quarks Superseded Atoms Now A Flash Of Energy May Shake Up Physics." The author Ronald Kotulak wrote it after interviewing Rob Harris, who was careful enough to downplay the practical significance of the CDF find. Harris clearly explained to Kotulak that the theory was probably wrong, as he is quoted to say "If one were a betting person, one would tend to bet that it's more likely to be an error in the calculations than it is to be a new quark substructure." That sentence was the cause of the mention of "bad math" in the title! Because of the Chicago Tribune article Harris got a number of unpleasant comments from colleagues who thought that too much emphasis had been put on new physics; but it really was not his fault. Indeed, to many the fault was in the way the whole interaction with the press had been managed by the spokespersons. Bellettini in particular became the target of the criticism; however, rather than being expressed openly in the appropriate venues, which would have been the Executive Board meeting or the associated mailing list, the criticism remained at the level of corridor rumor, a sort of stomach rumble for the collaboration. As such, it was even worse than a public trial, as Bellettini never got a chance to defend his actions in front of his collaborators.
The only surfacing critique of Bellettini's action was a letter which Avi Yagil posted on February 9th to the CDFNEWS forum, a mailing list where CDF members mainly exchanged news about papers in preparation, meeting times, or newborn babies; but also one which, unlike the executive board mailing list, reached all CDF members. In his posting Avi summarized the result of a discussion of the situation with colleagues who like him resented the way the interaction with the media had been handled. He explained that the spokespersons had the right to speak on behalf of the experiment, but were not supposed to confuse their own opinions with the ones of those they represented.
Avi's summary is believed to have had one notable effect when in 1997 the first term of Bellettini expired: he declared his availability to serve for another term, but he lost the election. It seems as if the media-wary soul of the collaboration did not forgive him for the way newspapers and outreach magazines had covered and over-hyped the jet ET excess. In retrospect, I believe Bellettini was guilty: guilty of believing that creating attention on particle physics and explaining to laymen the excitement of a possible new CDF discovery was in the interest of the experiment. There lay the mistake: it was in the interest of the progress of science, but against the interest of some of his colleagues.
As for Brenna Flaugher, she was left with a sour taste from the whole story. After the media storm of February 1996 she had to withstand open criticism from her colleagues that had nothing to do with the analysis of the data but a lot to do with how Bellettini had been presenting it. She was surprised that people also resented the way she described the hypothesis of compositeness in presenting the results at conferences and in interactions with science reporters. There was nothing new or unusual in testing compositeness with the high-jet-ET data; theoretical papers had repeated for 20 years that this was one of the most important ways to test the standard model. Her presentations and the paper were careful to point out that the difference between data and theory could be due to the PDFs used in the theory. The fact that the press had gotten interested in the science that CDF was doing should have been a positive thing. Eventually, Brenna got more interested in building detectors and let other people fight what were clearly more political battles than physics arguments.
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