Monday, July 30, 2007

On Target


So we went to see Sonic Youth at McCarren Pool in Brooklyn over the weekend. Pretty great to hear Daydream Nation played front-to-back. I'll leave the infinite regress of bellyaching about supporting nostalgia trips outside in yesterday's rain -- the music, issues, topics, etc. still sound wildly futuristic even now. The only thing that might date it is the fascination with 70's and 80's icons like Philip K. Dick (oops, people are still making movies of his books, and Blade Runner is being re-released again) and William Gibson (no more movies, but cyberspace anyone?) And maybe the song about the Preppie Murderer ("Eliminator, Jr."), whom I could find namechecked in only one online review -- how quickly things move into the past.

But I knew I recognized Lee Ranaldo's amps from somewhere: Jasper Johns: An Allegory of Painting, 1955-1965. Very sly sneaking in the modern art for the kids. Almost as sly as that huge Gerhard Richter candle...

Monday, July 23, 2007

Shapes of Things

Yow, the conservation of (blogging + life) holds true. I'm just back from a week in Montreal + Vermont, 5 days of which were spent attending the "ETD-HIC" (Early Time Dynamics in Heavy Ion Collisions) workshop at McGill. The workshop was mainly concerned with various approaches to modeling and measuring the microscopic dynamics of the very early stages of a nucleus-nucleus collision. Of course, many people think that this is easy: nuclei are made of hadrons, hadrons are made of quarks (and gluons), and we know the rules by which quarks and gluons interact. Sad part is, it's not: the stuff we make at RHIC acts far too much like a fluid to be merely composed of particulate quarks and gluons bouncing around via pair-wise interactions. So it was a lot of discussion of Color Glass Condensates, Color Fields (w/ Wiebel instabilities), Lattice QCD, etc., and various ways of probing these dynamics experimentally (especially "hard probes" like QCD jets and heavy quarks.)

Naturally, I was there pushing my favorite worldview: that most of the data points us to considering a very rapid equilibration of the system. So rapid that it might as well be immediate, or on size scales comparable to that of the Lorentz contracted nucleus (i.e. a size that decreases linearly with energy). Regardless of that precise time, it seems to thermalize so fast that the initial configuration of the nucleons themselves are "frozen" in time (e.g. as shown above, with the green circles representing the "participating" nuclei), and serve to initialize the spatial distribution of the matter. This then evolves hydrodynamically (ideal or otherwise) until it freezes out into the particles that hit our detectors. At the very least, one seems to need to consider this lumpy, fluctuating initial state to capture various systematics of the data (e.g. how it varies with system size, shape, etc.) Neat stuff (which is why I like to talk about it!)

Wednesday, July 11, 2007

2 Out of 3 Ain't Bad

As Gram Parsons once sang, "and they called me a man because I couldn't keep my great big mouth shut." I guess I'm a man now: my 3rd lecture is finally over (and posted on my feed). Lots of fun (and great questions from the students) but my throat is sore.

Anyway, I'll be leaving Tallahassee and FSU tomorrow. But for the absurd heat and humidity, it's been an interesting trip -- and it's back to the grind tomorrow.

Tuesday, July 10, 2007

Lecture One in the Sunshine State

This week I'm hanging out in Tallahassee, FL (staying only a few blocks from the governor's mansion, it seems -- too bad Jeb is gone now...) at the National Nuclear Physics Summer School, presenting a set of 3 lectures on RHIC physics. I'm also learning quite a bit about the state of modern nuclear physics, which actually becomes more interesting as I dig deeper into RHIC physics. People generally think that RHIC physics is somehow growing away from "normal" nuclear physics, e.g. nuclear structure, but the more we look, the more we realize that our results really "see" the nuclear wave function in some form or another -- although we see "snapshots" rather than steady state configurations. So why am I sitting in Ian Thompson's nice leactures, blogging about them rather than listening? Go figure.

Anyway, here's the first lecture given yesterday -- an extended version of my RHIC colloquium, with a few more details on centrality determination than i usually allow. More to come.

Thursday, July 05, 2007

Murray & Lev

What is Landau telling Gell-Mann? I'm not kidding -- I'm dying to know. If any readers know Gell-Mann personally, can you ask him? Interestingly, this photo (which I stumbled on after digging up my talks from 10 years ago in a forgotten directory...) sums up a lot of my interest in how QCD works.

Barring any real answer (but who knows?...) any ideas for captions would be welcome in the comments!