Peter Steinberg

Scenes from the Users' Meeting

Blogging about past events always reminds me of Stephen King's Langoliers, those little guys that clean up the left-behind past, making room for the future.  But while the memories were still fresh, I wanted to mention a few high points of the RHIC/AGS Users' Meeting we had last week. 

First and foremost, it's not a real meeting without merchandise.  This year, the organizers made a funny riff on the "near-perfect fluid" announcement with a new RHIC mug.  Serving up the perfect fluid, 24/7, up to 31 weeks a year!

We also had a talk from Tom Schlagel about the wave of the future in lab security, as specified by the now-famous "HSPD-12".  This is the directive from the Administration being propagated to all federal agencies, including the Department of Energy and thus to all the DOE labs to rationalize the ID system, with fingerprints, and background checks...and no additional funding to the labs to implement it.  You can tell I'm a big fan of this plan, especially if it's rolled out with no sensitivity to the varying security needs of the various institutions.  But if they introduce mug-shots instead of the usual ID photo, then I'm all for it!  This is clearly an alarming trend in the national labs, but I am heartened to see that the lab management is taking its implications very seriously and is looking out for the best interests of both lab employees as well as foreign visitors and remote users, all of whom are crucial components in the lab's reaseach.

We also saw the awarding of various prizes for student theses and posters,  several of which were won by some students who graduated from PHOBOS.  Go Abby and Carla!  Here is a shot of Abby receiving her Best Thesis award from BNL Lab Director Chaudhari (who didn't seem to recognize me as I rushed to the front...guess he's not reading my blog).  Let's hear it for the little experiments -- who will certainly be missed next year.

We also had a nice 2nd day of plenary sessions, incorporating summaries of the various workshops.  It was held in the Physics auditorium rather than the much larger BNL auditorium, and so didn't feel nearly as much like a special occasion.  This may have led to it being a bit more sparsely attended than Day 1, but it was still engaging (despite a clear drop in the energy level of most attendees, including yours truly).

But I cannot finish this post without a nod to the real engines of the Meeting, the staff of the RHIC/AGS Users' Office who made most of these events happen as if by magic.  We'd say "Let there be a Workshop in Building 490" and, Lo, There was a Workshop, with coffee and donuts, and printed agendas (fully up-to-date, daily), and laser pointers...and no hassle for the individual workshop organizers.  Anyway, here's a shot of Mercy and Kelly, with Angela's hand in the background (which was all she'd authorize of this photo ;-))  Thanks again, Susan, Angela, Mercy, Kelly - This could never have worked without all of you.

Safety Record of the Beast

  Safety Record of the Beast 
  Originally uploaded by entropybound.

BNL has placed more and more emphasis on safety in the workplace in the last several years.  As the recent article in the Chronicle mentioned, all of the labs are living in the shadow of the major SLAC shutdown after the accident on October 11, 2004.  And a couple of years ago, there were several incidents even here at BNL Chemistry, which really brought the issue into focus for many of us.  That said, it's encouraging to see we've gone nearly two years without major incident, but I hope it is just an accident that this was the number showing just today, the first time I've looked in several months.  Maybe it's a good day to make sure I safety training for *everything*...

Mermaids, Not Singing, or, Catching A Wave

  Mermaid Parade 6/25/05 
  Originally uploaded by entropybound.

This is only tangentially connected to anything work related.  On Saturday afternoon, I had a few hours to kill so I decided to do two things that I'd been planning to do for years: see Coney Island  (which is neat - a huge beach just an hour's subway ride from Manhattan), and see its famous "Mermaid Parade".  Hard to explain what it is, but I think this photo gives some flavor for 2 hours in the blazing sun, with lots of vintage cars, insane floats, and lots and lots of mermaids.  No complaints here. 

Now I noticed this morning on Boing Boing that there were over 2000 photos posted on Flickr, a photo site that I use to post often to Quantum Diaries.  So I decided to catch the wave and post 8 photos of the parade to my photoblog.  Then the fun started, as I realized that I spent about 2 hours on top of the page linked to on Boing Boing.  Within that period, the photo shown here leapfrogged past photos that have been available for months into my #1 spot.  Catching the wave, indeed...

Stealing Thunder With Tornadoes [Updated]

So I do my periodic scan of all things internet using Google's new portal site, and lo and behold, I see that "MIT physicists create new form of matter" on slashdot.  Now this was strange to me: hadn't we just seen MIT "Physicists serve up 'perfect' liquid"?  Was the MIT press office repeating itself?  Turns out that the atomic guys may once again be stealing our thunder, as the Ketterle group at MIT has created tiny tornadoes (i.e. vortices) in a rotating droplet of ultracold superfluid Lithium-6.  Don't they have enough Nobel Prizes already?  We've been through this story before with the "Observation of a Strongly Interacting Degenerate Fermi Gas of Atoms" (Feshbach resonance, infinite scattering length - similar to what's shown in the diagram to the right) but this is starting to hit closer to home:

The superfluid Fermi gas created at MIT can also serve as an easily controllable model system to study properties of much denser forms of fermionic matter such as solid superconductors, neutron stars or the quark-gluon plasma that existed in the early universe.

As soon as the users' meeting is finally over (almost there!), I'm going to have to think about this.  A lot.

[Update: I've thought about it a bit more.  It really can't be said that this result steals the thunder of the RHIC results, also showing near-perfect fluid behavior.  The RHIC result remains essentially weird, since RHIC doesn't have the means to trap the atoms, let them equilibrate, and then rotate the fluid - we just seem to make it every time we crash nuclei together.  But the overall similarity in the language points to the intriguing fact that very different systems at different temperatures (ranging from the sub-kelvin physics shown above, to the tera-kelvin physics at RHIC) can show fluid, and even perfect fluid behavior.  So rather than competition, it's an elegant example of the generality of physical law.  Neat, eh?  But I still want to know who's eventually going to get a Nobel prize for this...]

RHIC/AGS Users' Meeting @ BNL

Following on the heels of a hectic weekend where some of my good friends got married in Battery Park, I am now up to my eyeballs in workshops as part of the RHIC/AGS Users' Meeting at the lab (the AGS being the venerable synchrotron which has been one of BNL's workhorse machines since the main '60s).    It's a week of workshops  on various aspects of heavy ion physics (for instance this one on "high pT physics" I attended this morning) and spin physics, ending with a two day plenary session on Thursday and Friday. My involvement isn't with any particular meeting, but with organizing the whole set of eight running from this morning until wednesday afternoon -- mainly damage control and technical assistance. It's going OK so far, but you never know what will happen: so if I happen survive the week, someone please buy me a drink...

My Double Life

This post is mainly a plug for a paper I put on the archive recently, in collaboration with my South African colleagues back in Cape Town.  Rather than being written by my real self, the experimental nuclear physicist that I'm paid to be, this one is written by my double, who dabbles in "phenomenology" (a word that confused the heck out of me as a philosophy student, confusing it with dudes like Husserl etc., but is just the application of theoretical models to experimental data!). 

In this work, my colleagues and I address a somewhat-confusing issue from an already-somewhat confusing (and still somewhat controversial) paper I wrote with my PHOBOS collaborators several years ago.  That latter work was a systematic comparison of the total number of charged particles produced in the collisions of various systems as a function of beam energy, be they nucleus-nucleus, proton-proton, or even electron-positron (when the latter annihilate into quarks and radiate hadrons as "jets" -- we've seen this before in previous blog posts). 

The weird part was that at higher energies (30 GeV and above, for those familiar with the lingo), the multiplicities in nucleus-nucleus collisions (divided by the number of participating nucleons) as a function of the beam energy, were the same as the multiplicities measured in the electron-positron annihilations.  Now why is it weird for things to be the same? -- usually things are "anomalous" when things that should be the same are different, contrary to expectations.   The long and the short of it is that there are no two systems which should be more different than two pointlike quarks fragmenting into other quarks and gluons, and a messy collision of two nuclei: but the two systems track each other pretty well (but of course not perfectly: this is data, folks) as the beam energies change by a factor of 10.  That's also pretty anomalous. 

Speaking informally (as we do when we're afraid we might be wrong...) all of this might make sense one entertains the possibility that the small strongly-interacting systems which are formed in e+e- annihilations can also be described as little drops of the same near-ideal fluid we make at RHIC (perhaps in some kind of "dual" way).  It wouldn't be the first time this was suggested (it's floating around the literature if you look), but it's striking how far this assumption can get you when you use it for phenomenology, both thermodynamical and even hydrodynamical.

This brings me to the current paper.  It was always a nagging problem that the two systems began to diverge systematically below 30 GeV, with the number of particles produced in the nucleus nucleus collisions decreasing rapidly as the energy went down.  What my colleagues and I found was that the difference can be understood if one accounts for the energy bound up in the heavy baryons which have to be present at the end of the collision, simply because baryons are conserved (and they are).  And this can all be modeled very simply using both textbook thermodynamics (thermochemistry even - as implemented in the THERMUS package) as well as textbook statistical mechanics applied to the zoo of hadron states.  One can even make a pretty good analogy to how salt affects the way water freezes (see my slides from a couple of weeks ago...)  Too good to be true?  Probably -- but it was a lot of fun to put together with Jean, Spencer and Maciek (the last who probably didn't know what he was getting into when he wrote his undergrad thesis...).  Anyway, have a look: I'm always interested in getting feedback.

Just a footnote: speaking of double lives, it seems that I have a live double: a literary agent in New York named Peter Steinberg.  Someone I know even met him recently.  Strange coincidence, even if the whole doppelganger business creeps me out - but I certainly hope he's keeping up the high standards of the franchise.

RHIC Retreat on Shelter Island

I seem to be jumping from island to island these days: from Ellis Island back to Manhattan Island to Long Island and finally here, to Shelter Island (on the east end, between the North and South Forks).  The occasion is the yearly "RHIC Retreat", where the folks who run the accelerator gather for 3 days of reflecting on the successes and failures of the machine (read: the collider) over the last run.  Now it's not much of a "retreat": in fact it's really interesting participating in the very frank discussions between the experiments (why I'm here) and the machine people, as well as their interactions among themselves.  It's always important to remember that RHIC is a facility driven by the interactions between the machine and the experiments - and having a few drinks over dinner is a good way of fostering those interactions, right?

On Liberty

On Saturday I got a last-minute invitation to tag along with some friends entertaining some visiting family to do the Lower Manhattan Experience (Statue of Liberty, Ellis Island, and now the WTC site).  You wouldn't believe how fast I was out the door - when you live in NYC, you never actually do this kind of things, since it's always there and it's only the kind of thing you do with visitors.  (One friend of mine admitted, jealously even, that she had never been, after living here for years...)

Of course, once one reaches the last stop on the 1 train, one is immediately reminded of why one doesn't try this very often, as one finds oneself in teeming throngs of tourists.  You have to wait an hour in one line, just to wait another 45 minutes in a different one.  And getting on a ferry is about as strict as it is to get on a plane.  And they won't even let you up into the statue anymore if you arrive after lunch.

But once you get over the logistics of navigating the crowds, it becomes downright inspiring to experience the boatride around the statue accompanied by a wildly diverse crowd of people who've braved the same obstacles to share the boat with you.  It's easy to get swept up in the concept of the place, celebrating the US's longtime status as a haven for immigrants.  Being the product of quite a few vectors pointing out of quite a few countries on Europe's eastern edge (Ukraine, Lithuania, possibly Romania [right mom?]), it's hard not to get a little sentimental at how amazing it is that all those vectors could find a single place to converge, such as in enormous rooms like this one on Ellis Island.  Now I'm not going to belabor the point here, but it pains me no end to see how restrictive U.S. visa policies have become, making another long-standing point of convergence, U.S. Science itself, a less-welcoming destination for talented scientists trained abroad.  Is the sense of security we are supposedly gaining worth the cost of lost talent, forgone discoveries and an immense amount of lost goodwill? 

On Ellis Island, I found an unexpected acknowledgement of one of my personal vectors,  my great-grandmother Libby Steinberg who emigrated from the Ukraine in the late 19th century, on the "Great Wall" behind the main building.  Had she passed through New York on the way to Chicago?  Of course, this epiphany was shattered a few minutes later when I found that anyone with $100 and a relative on the immigration rolls can get their loved-one's name on the wall...but they disabled the reverse database lookups, so I may never know who got this there!

Anyway, as powerful as the experience was, it's a lot of boating, a lot of walking, and a lot of sun.  I could really relate to this girl by the time we wandered back to Manhattan to ponder the WTC memorial - amidst the crackle and boom of thunderclaps echoing off the skyscrapers staring down at us staring down into the Ground Zero site, which gets more and more full every time I see it...

Universe in a Shell

This post is a long time coming.  One of the first things I did after I started working on Quantum Diaries was to get my hands on as much of the RHIC-as-doomsday machine literature as I could find.  OK, it's not an extensive library by any measure, consisting of several "factual" books about avoiding major catastrophes to the human race (ones that utilize RHIC as a paradigmatic example of science as potentially dangerous and irresonsibly unchecked) and...a science fiction novel.  Of course, the more serious "scholar" type (which I at least aspire to be) went right for the "serious" books by Rees and Posner.  I read Rees a long time ago, and am still working on my sustained counterargument (which is developing over time), and I've made it through enough of the Posner to feel somewhat used (on behalf of my entire community) for his aim to make a compelling book (and one that requires most of us to be a little more of an economist than I still think is necessary to make these arguments...). 

So of course I put off the science fiction book, mainly because I expected so little from it, but partially because I also expected to feel used in this case as well.  I expected to see things that are deeply important to me deployed purely in the interests of maintaining an interesting storyline.  And Gregory Benford's Cosm certainly provides a great deal of grist for my frustration mill.  Benford is an astrophysicist from UC Irvine, and is clearly a well-known and well-respected author, both of fact and fiction (although I have not read any of his other works, basing this assessment on the sheer number of his published works, as well as the large number of usually-positive reviews one can find online.)  More importantly, he's well-known as a purveyor of "Hard SF", where some thought and attention to science fact is applied to the generation of fiction, giving readers a sense that the story could "really" happen.  In that context, my main reaction to the first section of Cosm was a combination of amusement and irritation, when I found that he was doing what looked to me more like journalism, or maybe anthropology.  I found characters and activities and attitudes that I recognized, but so much so that it felt like a transcription of certain parts of my daily life.  RHIC, its basic physics, its experiments, and even some of its people (e.g. my colleague Tom Ludlam) are rendered with reasonable (and sometimes excessive) accuracy, almost as if it were out of a missing chapter of Sharon Traweek's anthropological work on High Energy Physics, "Beamtimes and Lifetimes". 

The endnotes make this less surprising in retrospect, since the background of the novel was based on visits to BNL and RHIC in the early 90's.  And that offered yet another angle, since most of the physics discussed in the book was state-of-the-art in 1990, and thus feels a little...well...old by now.  And yet, I will probably never forget the jolt of finishing one of the early chapters, turning the page, and being faced with a bold-faced "MAY 2005" at the start of the next.  Same jolt one gets at a reunion with old acquaintances after 20 years, as you attempt to reconcile your expectations of the future with that selfsame future as it has actually played-out.

And yet, Benford was creepily prescient in his most important plot device, that RHIC would do something to stress-test the known laws of nature in a tiny volume in such a way that a small region of space-time would be created with different laws.  Fortunately, he didn't go straight to the scary stuff, making some sort of runaway chain reaction that engulfed the known universe at the speed of light.  That would obviously have led to a very short book.  Nor did he take the RHIC language of the "little bang" seriously, and have us (or "them", in the sci-fi world?) create a new universe out of our primordial strongly-interacting liquid.  Instead, he postulated a scientific hail-mary where the densities were so high that the matter led to the opening up of a wormhole, offering a window onto a completely different universe, but one somehow sealed off from our own in a basketball-sized "shell".  While his conceit is a little extreme, he clearly captured the longstanding fascination of heavy ion of physics, where things would get so hot, so dense, and complex that essentially anything could happen.   Vestiges of this attitude persist in the field, but I'll discuss that some other time (feel free to bug me...)

Of course, once this sphere (eventually nicknamed "Cosm") is created, the rest of the plot follows inexorably, driven by the tension between the thesis and antithesis of the scientific enterprise: the lone-wolf physicist (here embodied by Alicia Butterworth, a physicist teaching at UC Irvine -- allowing some exploration of east vs. west coast styles of physics), obsessed with understanding her unexpected creation, and the enormous scientific and academic bureaucracy that, while designed to protect and foster scientific research, inevitably feels pressure to place limits on it on all sides, in the name of safety and accountability.  Benford makes some effort to show that both are necessary aspects of the science-research ecosystem, but it's clear where he bets  his money: with the renegade who reluctantly, but compulsively, bends the bureaucratic rules in the pursuit of pure knowledge.  Somewhat cliched to be sure (as were most of the characterizations, my overarching problem with the book as a piece of literature), but ultimately ringing true, and enjoyable in the way that it offered situations that are familiar to anyone who's ever had to muddle through the up and downs of a research project where you don't even know what you're studying, much less how to study it.

How Experiments End

Despite not-even-veiled threats by colleagues from PHENIX to bring a wooden stake to the next Experiment/Machine Meeting (just in case we really do ask for more data next year!), I really think this is it for PHOBOS.  One can see it in what may be our final logbook entry as a running experiment, written by my colleague Gerrit (who has been working on PHOBOS since 1994):

(06/08 12:18 G. Nieuwenhuizen & P. Steinberg) Switched off chiller.
Switched off cooling system through main key switch.
Switched off silicon air blower.
Disconnected powercords of all silicon FEC powersupplies.
Disconnected powercords of all silicon bias supplies.
Switched off TOF CAMAC crates.
Switched off trigger NIM bins and CAMAC crates on positive and negative side.
Switched off trigger Keithley scanning multimeters on positive and negative side.
Switched off PCal powersupplies on positive and negative side.
Switched off SpeCal powersupply, cosmic HV supplies and NIM bins.
-----------------------------------------------------------------
Last one to leave switches off the light.

This may be less apparently-eloquent than some of the meditations of Peter Galison (excellent historian of science, and the previous tenant of my first grad-school apartment...we used to get his mail) on "How Experiments End", but it's no less moving for those of us who've been involved with this project as long as we have.  Still, I like Galison's final words:

Thinking back over a long career of fieldwork, Claude Levi-Strauss paused to comment on the near-universal veneration of the sunset.  Why, he asked, should the sun's retirement command so much more interest than the geometrically similar sunrise?  Sunrises, according to the anthropologist, may suggest something of the weather to come.  But the sunset, refracted through the dest and droplets kicked up by all that has happened, recounts in compressed form the whole story of the day.  The end of an experiment resembles this sunset, recapitulating in a human context the encounter of reason with the world.

We'll see about this reason vs. world part, when we actually get our Quark Matter 2005 results ready by August for presentation in Budapest, Hungary!  Needless to say, since data analysis can continue for years, collaborations have a much longer afterlife than the duration of the data taking.

A World Year Beach Walk

I was recently asked by the BNL public affairs folks to give a presentation to the Brookhaven Executive Roundtable, which gathers lab people, community people, and representatives from the US government (including Department of Energy and even a representative from NY Senator Schumer).  My task was multiple: to try and convey a sense of the physicist's outlook on things, to give some details about Einstein and the World Year 2005, to discuss the research being done at RHIC as clearly as I could, and finally to say a few words about Quantum Diaries itself.  Here's the final result, if you're interested...

QGP on CD

 

I have mentioned the RHIC "Whitepapers" in previous posts, mainly since their public availability was associated with a major press release just this past April.  What I hadn't appreciated was that we'd get a nice CD out of the bargain, almost free of charge, with renderings of our iconic event displays.

This is great. I've always dreamed of releasing a CD...but I never thought I'd have to share the credit with 1000 other scientists!

PHOBOS Rising (for the last time...)

I know we're not a phoenix (inside RHIC joke...PHENIX, get it?), but PHOBOS has come back from the dead (or a two-month suspended animation at least) this week for our last hurrah as a running experiment.

The special occasion is RHIC running of polarized proton-proton collisions at the highest energy reached so far - 410 GeV, a bit short of energy reached by the SppS proton-antiproton collider in the early 80's, but pretty high nonetheless.  Of course, no-one is expecting to find any new particles (that's not our job at RHIC!), but in the last few days, the accelerator people reached a major milestone for the machine in their goal to help the other experiments resolve the famous "proton spin puzzle" (we all know that a proton has spin-1/2, but we don't know how it's distributed among the constituent quarks and gluons). 

PHOBOS isn't much of a spin experiment, but we're very interested in doing one of the things we really like to do - count the particles emitted in the collsion.  A few years ago, we realized that there were some intriguing connections between the number of particles produced in gold-gold collisions at some energy, and proton-proton collisions at *twice* the energy.  Thus, the 410 GeV (a little more than 2x the 200 GeV we've run already) offers some simple, but exciting, physics to do in our last hours.  So we're all keeping our fingers crossed for this evening!