Now that the school year is over, and I’m only working one job instead of two, I have just a little more time on my hands to catch up on things that I’m backlogged on.  One thing that I’m finally getting some traction on is my reading of Physics Today, the monthly magazine published by the American Institute of Physics that is a benefit of membership to any of AIP’s member societies (including the American Physical Society).  It really is a nice publication, and I wish I could keep up with it more, as there is often timely news in there that is less timely by the time I get to it.  (Don’t even get me started on American Scientist, the high-quality magazine of Sigma Xi, which I also really enjoy for its well-written articles on all scientific fields, which I think I’m now a year behind on.)

Anyhow, I have finally managed to finish Physics April (before the end of May, even!).  I’m glad I got to this particular edition, which was devoted to John Wheeler (1911-2008), a theoretician who spent many years on faculty at Princeton.  I had certainly heard of the guy, and definitely had it in the back of my head that he was Richard Feynman’s thesis adviser, and had co-written an important textbook on general relativity.

But the April articles taught me that he was so much more than that!  Wheeler started out in nuclear physics, where he worked with Niels Bohr to develop the liquid-drop model of nuclear physics, and helped develop the atomic and hydrogen bombs.  But in the 1950’s, he had the courage to completely change his field of research, and started working in general relativity.  I had no idea that at the time, GR was considered something of an intellectual backwater.  But he developed many interesting GR concepts, such as the black hole (he invented that famous name too) and the possibility of gravitational waves (which I’ve discussed here before).  And then, still later in life, he made another switch and started exploring issues of quantum measurement, which at the time was considered best left to philosophers.  That too he made into a scientifically rigorous pursuit.  (Philosophy is also rigorous, but not in the same way!)

But all the more amazing is that in the midst of all this, he mentored a very large number of students, many of whom became leaders of the field in their own right.  In forty years at Princeton, he supervised 43 PhD theses and another 43 senior undergraduate theses.  As a professor myself, that’s many more students than I could ever imagine working with, if nothing else because good mentoring can be so time-intensive (and I don’t even claim to be a good mentor, necessarily).  When I read about the likes of Wheeler, I sometimes wonder why I bother to come in to work each day.  But I suppose we all find our little ways to contribute.

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Since the detectors were ready for proton collisions last year before the explosion in the LHC forced a long delay for repairs, you might think we have nothing to do but wait right now (for those of us not working on the repairs).  After all, we were ready last year, weren’t we?  Well, yes and no.  I, for one, am busier now than I have been in quite a while.
While we were definitely ready for data last year, we were only expecting to have a short data-taking period before the usual long winter shutdown of the LHC.  So we planned to use the small amount of data during the long shut down to calibrate our detector and prepare for a longer run where we could accumulate enough good data to produce our first results.
After the LHC incident, we instead ran our detector for several months with no beam, and accumulated data about millions and millions of muons traveling through our detector.  And in fact with these data we have been able to do much of the calibration work we had planned to do anyway with the collision data.  So we’ve still been able to do a lot of the calibration we planned to do, although we haven’t been able to do all we could have done with collision data.
We also always have some small parts of our detector which fail and need to be repaired or replaced.  And we also have found that a few things that need to be extremely reliable (such as parts to transmit our data from usually inaccesible places underground to the surface that we rarely have access to for repairs) that we installed last year just weren’t as reliable as they were supposed to be and already need to be replaced with redesigned parts.  So this part of our work also hasn’t changed much with the LHC delay.
Another thing we are working on right now is putting in place software to analyze the first data when we get it.  While we were ready to record data last year, we did not have done all the software tools to analyze it quickly.  If we have collisions this year, we plan to already have in place the tools to analyze that data and have first results ready in a few months.
Finally, we found out a few months ago that next year’s run of the LHC will be at a slightly lower energy than the final design calls for (10 TeV instead of 14 TeV).  This affects us a bit because our simulations were done with the 14TeV energy in mind, so re-doing these simulations at 10TeV is another thing people have been working on.
So we are quite busy, and not just waiting for the LHC folks to finish the repairs.  But whenever the repairs are done, we will be even more ready for the data than last year!

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While having a snack before my early evening meeting a few weeks ago, I picked up a copy of the CERN Bulletin to read. One of the articles I read was a column by the CERN Director General called Living in the spotlight, in which he discusses the benefits, pitfalls, and responsibilities of communicating with the public and the media. It occurs to me that now, with the schedule confusions of last fall receding into the past and our new start date still months away, may be a great time to discuss some of these issues in principle, without the backdrop of current events. Director General Heuer writes:

Particle physics has always operated in a fully open and transparent way. It’s in our DNA to do so. Meetings are open to all comers, and it is important that we continue to foster such a culture of transparency. Nevertheless, we need to be aware that we are much more in the public spotlight than ever before.

We have to be aware that when we are speaking to colleagues in open meetings, giving stories to our home institutions’ internal publications, or writing messages to the CERN community in the Bulletin, the eyes of the world are on us. That doesn’t mean that we should be less candid than we’ve been in the past, but it does imply a greater degree of responsibility in the way we communicate. We must be sure that what we are saying avoids any kind of particle physics ‘shorthand’ that could be misinterpreted, and that results are not communicated until they have passed normal internal peer review procedures.

I agree completely with Dr. Heuer.  Our collective scientific effort benefits from communicating information openly, and particle physicists have long been pioneers in developing systems for quick global communication of our results.  But in a time of increased (and extremely welcome) public interest in our work, we should take some care in the way we express ourselves.  The question is not what we can talk about in public; we can talk about almost everything. Rather, the question is: what are the rare exceptions to that rule?

The policies of the ATLAS experiment, which I work on, specify two things that collaboration members can’t talk about in public fora.  First, we can’t reveal experimental results in progress.  The reason most often cited for this is that we want to be sure of our answers before we present them publicly, which is extremely important, but personally I think that there’s also an issue of giving credit where credit is due.  Internally, there are many people working on many things that will contribute to a final experimental measurement; there may be multiple parallel analyses that will later be merged, and there are many lower-level efforts that will contribute to any given analysis.  I think it’s important to acknowledge that no ATLAS result will ever be the work of a single person, and it’s important to present our collective discoveries in a way that’s acceptable to all the contributors.  In practice, this means a fairly long process for paper approval and an author list that runs to about ten pages, but that’s the best system we’ve got.

The other limitation in the ATLAS policy on public communication is that we can’t talk about other peoples’ private comments or remarks in internal meetings.  This is simply a matter of general courtesy; our work would be pretty unpleasant if anything we said or did might show up in a public forum.  So as great as it would be to make a blog entry out of an entertaining story about my advisor, I can’t.  In fact, I cannot publicly confirm or deny that there are any entertaining stories about my advisor at all.

Although I’m officially bound only by the rules of my experiment, I believe that there are broader reasons to be careful about public comments.  We want to give an accurate sense of what our work is like, and an accurate impression of our present understanding of how the universe works.  (For some audiences, that actually means emphasizing clarity over detailed accuracy, but that’s a question of tactics rather than strategy.)   We should also extend basic politeness to colleagues in a broader sense than simply our own experiments; people on other projects and at other labs deserve the same respect we give our coworkers.

I would even say it’s appropriate to take care to portray particle physics and its institutions in a positive light — but I need to be clear about the reasons for, and the limits of, that statement.  I try, in what I say publicly, to explain the importance that I see and the excitement that I feel about the work I’m a part of; in other words, I want to portray it in a positive light because I see it in a positive light.  But when mistakes are made or problems arise, the overriding public interest and the ultimate interest of the field is in an accurate portrayal of how things are going.  We should be willing to publicly discuss problems and give constructive criticism.  Such discussions help us improve, and only if we’re willing to have them do the ordinarily positive things we say become believable and useful to all of you out there.

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Angels and Demons opened today here in Geneva, and I just got back from seeing it with a big group of my friends from CERN.  (There was also a special early showing last week, which a few people I know went to, but I was neither lucky enough to get a ticket in the drawing nor important enough to get an automatic invitation.)   We had a good time, especially with the opening.  It had a lot of images from CERN — along with a lot that weren’t — and a lot of real particle physics terminology.  Everything was rather scrambled.  For example, a “luminosity of ten to the thirty-four” is a real measure of the intensity of the LHC’s collisions, but it’s a figure that will take years and significant upgrades (rather than minutes) to attain.  Overall, the introduction gave us plenty of occasions for laughter, which the other movie-goers may have thought odd — unless they were from CERN too.   Probably people who are knowledgeable about the Catholic church or renaissance art will find other parts of the movie equally mixed-up and entertaining.

I’m not spoiling much if I say that CERN’s critical role in the movie is producing a quarter of a gram of antimatter which is then used to threaten a large part of Rome with destruction.  Antimatter really exists, that amount of it really could do what they said, and antimatter really is made and studied at particle physics laboratories like CERN.  But it would take millions of years to produce that much at the present rate, and we don’t have the technology to store it even for even a fraction of a second in order to study it.  I have a friend at Berkeley who works on an experiment at CERN to do exactly that, a few atoms at a time, but storing antimatter in visible quantities as an energy source is probably further from our current level of technology than mining hydrogen from the atmosphere of Jupiter and sending it back to earth.

The most frustrating part for physicists about the portrayal of antimatter is the way it seems to be magically produced for “free” energy.  The universe never works that way: energy is conserved, which means that even with amazing technology you’d have to put in as much or more energy to make the antimatter as you’d get out later.  There’s no such thing as a free lunch.  The religious overtones put on the antimatter production, and on the woefully mis-nicknamed “God particle,” are also rather frustrating and inaccurate.  Yes, we think that the Higgs boson or something like it is involved in producing some of the mass in the universe — but no, that doesn’t tell us anything about the book of Genesis or the meaning of life, the universe, and everything.

So let me be clear: we neither want nor expect to find the answers to any religious mysteries in our studies at  the LHC.  We also won’t make “red matter” like you saw in Star Trek — that’s entirely fictional.  CERN doesn’t have a space plane or a secret vault with the seventh horocrux.  The lab cafeteria does not serve soylent green, although it does have an excellent salad bar.

For more serious and detailed answers about the fact and fiction of Angels and Demons, CERN has a new website: angelsanddemons.cern.ch

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For background, see Peter’s entry here: S.O.S. (i.e. Save Austrian Science)

Since the announcement that Austria plans to leave CERN, I’ve seen a number of invitations to sign the petition asking the Austrian government to reconsider. Everyone I know who’s discussed the subject has said the same thing: the Austrian government is making a grave and shortsighted mistake.   I’m not particularly well informed on the background or details, and particle physicists do like to be collegial, so I feel odd disagreeing publicly; however, I would like to make the case that the decision is less black-and-white than many seem to think it, and that it’s not really my place to intervene any which way in the decision.

The latter argument, that I shouldn’t sign the petition, seems to be an easy case to make by analogy from an American perspective. The policies of the United States are made by the elected representatives of the American people, and in particular U.S. science policy ought to be made by those representatives with the advice of American scientists. If a Senator or Representative received a petition that was signed mostly by foreigners, even well-informed foreigners, I imagine that he or she would disregard it.  Frankly, I think that’s the right thing to do; while we can often take our instinct to “go it alone” too far, most Americans want their government to make decisions based on their interests rather than agglomerated international opinion. Why would we expect the Austrian government to make decisions any differently? In order to remain in CERN, the Austrian government must be convinced that it’s good for Austrian science to spend the money, and it’s Austrian scientists who are in the best position to make that case.

My personal opinion is that leaving CERN is indeed a bad idea for Austria — they are casting aside their long-term involvement in Europe’s greatest scientific endeavor, and that’s not something that will be easily restored — but the question is complex.  Certainly it’s bad news for Austrian particle physicists: their participation and opportunities at CERN will certainly be curtailed.  However, I doubt it will be eliminated; like the United States and other observers, their citizens and universities will likely continue to participate in CERN on an experiment-by-experiment basis.  They may not be able to send very many summer students or fellows to CERN anymore, but they can still fund their own summer programs at CERN (as America has) and send their scientists to work here.  The Austrian government has what seems to be a sensible argument for why it’s good for Austrian science to withdraw — given their limited resources, the CERN contribution uses about 70% of their budget for international science collaboration, and they propose to spend that money on other projects.

Could withdrawing from CERN really be beneficial for Austrian science as a whole?  I have no idea, and I doubt that all Austrian scientists will agree.  But they should make their case, and then Austria should decide the question on its own — without worrying about my signature on a petition.

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I can’t believe I’m the first to post about this, since it’s “ancient” news (i.e. from last week).  But if you missed it, Austria is planning on pulling out of CERN after 50 years involvement.  The claim is that they can use the money (about $21M) elsewhere in the EU.

Anyway, don’t think that the Austrian scientific community is taking the news well.  They are getting organized and already have a petition online.  Please take a minute and sign it:

http://sos.teilchen.at/petition/

It came as a surprise when Federal Minister Hahn announced that he wanted to discontinue Austria’s membership in CERN.

This “wrong historic decision” (quoting Prof. Dr. Herbert Pietschmann) must be stopped before Austria’s reputation as a nation of high-tech and modern research suffers irreparable damage and our country excludes itself from future developments.

CERN – this is research in elementary particle physics and comology. CERN is a brilliant example of excellence by European cooperation. CERN is the vision of our young scientists.

By signing this petition I urge the Austrian parliament not to agree to this proposition of minister Hahn.

(And I hope no-one missed that ATLAS slide in the AP article!)

(Thanks, Heinz and Paul!)

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It’s sort of sad to see last day of the conference — all the exhibits were broken down by this morning, and while we sat through the first session of the morning all of the registration booths disappeared. (A number of friends disappeared, too, before I had a chance to say goodbye. But this is particle physics; I’ll see them again somewhere else.)

However, there were still some talks not to be missed. The morning started off with a plenary talk by my CMS colleague Paris Sphicas, who talked about the physics of the LHC and the plans for early data-taking and physics analysis. I thought it was a good compact presentation of what we’re doing. And, in classic Paris style, he manged to flip through more than 60 PowerPoint slides in 30 minutes! I also enjoyed hearing from Jim Cronin, who won a Nobel for his co-discovery of CP violation in the kaon system in 1964, and then became one of the founders of the Auger cosmic-ray experiment in Argentina. I first met Jim when I was an undergraduate at the University of Chicago, and it’s always a pleasure to see him. He reviewed our current understanding of the highest-energy cosmic rays, whose points of origin appear to be correlated with the location of active galactic nuclei. He also showed us some Auger data which he pretty much admitted — proudly — hadn’t been fully vetted by the collaboration. I couldn’t get away with that myself.

The APS meeting is also an opportunity to honor some of our high-achieving colleagues. Gaston Gutierrez won the Bouchet Award and Aldo Menzione and Luciano Ristori won the Panofsky Prize for Experimental Physics. Gaston and Luciano gave presentations on their work on deploying matrix-element techniques for studying the top quark and the development of silicon-based trackers and triggers (respectively), both of which were really excellent achievements.

And after that there was just enough time for a pleasant lunch with Paris (where we tried to figure out what we should be worried about in CMS computing) before I had to catch the shuttle to the Denver airport. (Free WiFi here, by the way!) I’ll be back in Lincoln shortly…for about a day and a half!

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Today opened with some interesting plenary talks. One was on the state of nuclear energy. Nuclear power is of course a way to provide energy without using fossil fuels and without releasing greenhouse gases that can promote global warming — a double win. However, there are still issues to be addressed with what to do with spent fuel and the possibility of proliferation. What came across to me is that nuclear power-plant technology has now been frozen for several decades, as no new nuclear plants have come online in that time. Robert Rosner, the speaker, said that what we really need to do is apply modern tools to the problem. He pointed out that the Boeing 777 never had a physical prototype; the entire design was done with computer simulations, and the first aircraft produced from the design was immediately used to carry passengers. If we trust that design process, why can’t we apply it to nuclear power plants? However, given that the entire field has been frozen, we can’t expect new results to come quickly; it will be decades before nuclear power will have a significant impact on energy or environmental problems.

We also had a talk from Richard Muller, whose book “Physics for Future Presidents” was recently published. He discussed a physics approach to terrorist threats, and concluded that he is more concerned about the damage that can be done by an airplane (ala 9/11) than about small nuclear devices that might be produced by rogue states. I must admit that both talks made me think — why am I not working on these problems?

After that, I took part in a press briefing in which I and other LHC scientists talked to various reporters about the status of the machine and the work that we are all doing with it. I’m not sure if anything I said will see the light of day, but I was glad to have the chance to be interviewed by German National Radio (in English, thank goodness).

Another highlight of the day for me was a session sponsored by the Forum on the History of Physics, which featured several presentations on the history of major accelerator efforts. Stan Wojcicki of Stanford gave us his personal impressions of the history of the SSC (of blessed memory). I hadn’t realized how quickly some aspects of that project had moved along, and it seemed to me that perhaps there hadn’t been enough time for contemplation along the way. Let’s hope that we’ve learned our lessons from that era.

I must admit that I’m feeling some conference fatigue at this point. But I’m looking forward to some of tomorrow’s presentations — more about that after I get home.

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This morning I gave my conference talk, which was about top-quark physics at the LHC. The other speakers in the session were Tim Tait, a theorist who does a lot of work on new physics that involves top, and Vernoica Sorin, who discussed recent results on top from the Tevatron. I enjoyed their talks; the Tevatron has done so much good work on top, and it’s interesting to hear the new theory ideas that were out there. My presentation went fine, thanks, although it would have been even better if we had some LHC data at this point and could actually show some real top-quark measurements. I wonder what the chances are that I could get this gig next year, when there will be more to say. (Probably small.)
I also attended a couple of events related to women in physics. There was an invited session featuring the research work of several women in experimental particle physics (Marjorie Corcoran, Daniela Bortoletto and Deborah Harris), followed by a panel discussion. All of them have faced a variety of challenges in juggling a career in research science with raising a family. I asked them about what sort of family-friendly policies they wished they had at their institutions, and all of them cited paternity leave for new fathers. I was glad to hear this — as a relatively new father myself, I’ve been on the warpath about such things lately. I do think that changes that we make that are good for women in physics will ultimately be good for the men in physics too. All of us in this line of work love doing what we do, but it’s important to find some work-life balance.
The most recent past president of the APS gave an address in the early evening, which I was able to hear a little bit of before meeting some friends from graduate school for dinner. He cited efforts that the Society has made to improve the training of physics teachers.  Public education is a very important part of what the APS does, and educating future educators is a way to leverage resources and have a greater impact on the problem.  These programs have been quite successful so far.  As it happens, one of the friends I had dinner with now works on these programs for APS, so we got to talk a bit about that.

OK, two days down — only two more days of this marathon to go!

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Here I am in Denver for the April Meeting of the American Physical Society.  I know, it’s actually May, but sometimes the April Meeting ends up in May.  I haven’t been to an APS April Meeting in twelve years, because the virtues of this meeting are also its vices.  And what are those?  The conference is overwhelming, really.  The program is really enormous, with a very large number of parallel sessions.  It’s impossible to get to everything that sounds interesting.  And the days are awfully full.  I enjoy hearing a seminar about physics once or twice a week, but at APS you get seminars all day for four straight days.  I must admit that some talks I don’t listen to so carefully, so that my brain doesn’t get too full.

But the largeness of the conference is also a virtue, and as a result I’m quite glad that I came.  I’m seeing a lot of old friends whom I haven’t seen for a long time, and I’ve been in the field long enough (twenty years) that they come from all the different phases of my life, be it my very first physics teacher or my officemate from graduate school or people I worked with as a postdoc or some of the people I was with in San Diego last week.  Over lunch, I asked people why we should even have conferences anymore.  It used to be that the only way you could find out what was going on was by going to a conference, and in many research groups, someone who had gone to a conference was expected to give a talk about what happened there when they returned.  Of course now we have the Internet and new scientific information is disseminated very quickly.  But everyone agreed that the value was in getting to see so many people face to face, and also being pulled out of your day-to-day tasks so you could think about other things.  So yes, I should try to come to APS more often.  (But how often is it only one plane flight away from Lincoln?)

But OK, the science — what happened here today?  There was a plenary session this morning, and the leadoff talk was about results from the Fermi/GLAST telescope, which was launched last year.  I don’t want to say much about this because I don’t claim to understand it at all well, but besides doing things like discovering lots of new objects in the sky that produce high-energy photons, they are also observing electron and positrons in space at a rate consistent with the PAMELA experiment, which (as I understand it) could be explained by dark matter.  (I have perhaps garbled this; another blogger might do better with it.)  There was also a good talk about simulations of merging black holes.

I also attended some parallel sessions on Higgs physics and neutrino physics, and then a panel discussion on large international science projects, featuring former CERN Director-General Christopher Llewelyn-Smith, Fermilab director Pier Oddone and Dennis Kovar, the director of the High Energy Physics program in the DOE Office of Science.  Some of the discussion was about whether the United States can be a reliable partner in international projects if we make a new federal budget every year, and projects only get funded year to year as a result.

I’ll try to write more tomorrow — I have to give my own talk in the morning, and I should look it over once more yet.

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I wanted to add a few points about the Daily Show piece on LHC safety.

First, it was great. I totally agree with Seth that it is amazing that a comedy show is one of the few places we can turn for an accurate picture of this story.  Most media outlets are more interested in scaring people with nonsense than giving an accurate picture of the lawsuit.  Although it isn’t surprising given the profit motive.

Second, this piece almost didn’t happen.  The Daily Show wanted to do a piece on the LHC, and contacted US media people about it.  The reaction was not totally enthusiastic, as it was possible whoever got interviewed would be made to look foolish on camera.  The Daily Show eventually decided to ask for permission to come to CERN, and CERN had to be convinced this was a good idea.  Why should we let a comedy show not only come to CERN but even film in the tunnel?  Fortunately, the decision was made to allow them to come.

This is a great example of getting a message out about CERN in an unconventional way (another example might be making a rap video at CERN).  I think the lesson is that when the truth is on your side, it is better to be as open as possible.  The scientific attitude is that all points of view should be heard.  All theories are tested and only the ones that can stand up to scrutiny remain.

Finally, a few of us here at CERN had lunch with John Oliver (photo here), and we told him people were nervous about the Daily Show visit.  He said basically that “we are on your side” and it would be obvious to anyone watching the piece how seriously Mr. Wagner should be taken.  He said that they often do these kind of pieces and of course they always attack the person they agree with and agree with the other person for comedic effect.  But the other person is always happy with the piece when it airs, no matter how bad they are made to look, and usually they request a DVD of the piece to show their friends and family.  It makes you question their true motive.

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It is pretty remarkable that the Daily Show has produced a more accurate discussion of the safety of the Large Hadron Collider than many professional media outlets. You can see it here.

I’m so jealous of the people who got to meet John Oliver when he was at CERN!

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