The Race for Absolute Zero

The second half of the NOVA special on "Absolute Zero" aired last night. Like the first installment, it was very well done, avoiding most of the traps of modern pop-science television. There were some mysterious shots of amusement park rides when they started talking about quantum mechanics, and I'm not sure why, but they kept the "re-enactments" to a minimum, and didn't overdo the CGI.

They also deserve special mention for not insulting the viewers' intelligence with constant recaps.

As you can guess from the title, this part of the story covered the history of attempts to reach ever-lower temperatures. The first half-hour was spent on the race between James Dewar and Heike Kammerlingh Onnes to liquify helium, then there were 15-20 minutes on the race for Bose-Einstein Condensation, closing with a few minutes of cool things you can do with BEC.

Unsurprisingly, I was happier with the older material than with the BEC section-- I know the BEC stuff already, and it's much easier for me to spot elisions and hand-waves there. Stepping back a bit, I think the overall presentation was very good, and it was particularly nice to see Dan Kleppner get his due. I was disappointed by a few things, though.

For one thing, I was a little disappointed to not see any of the 1997 Nobel laureates for laser cooling. This is partly just a personal parochial interest-- I worked for Bill Phillips-- but they really didn't explain laser cooling much at all, and I thought it could've used more time. I understand why they did it, because taking time out to discuss laser cooling would've broken the symmetry between the Onnes-Dewar race and the Cornell/Wieman- Ketterle race, but I think they missed and opportunity here.

Spending more time on laser cooling also would've left less time for applications, which might not have been a Bad Thing. They only really talked about two applications of BEC-- Seth Lloyd and Peter Shor talked about quantum computing in a way that will make Dave Bacon and Scott Aaronson thorw things at the tv, and Lene Hau talked about "slow light."

I really could've done without the "slow light" bit. It's one of the most overhyped results in the entire field, but more importantly, it doesn't even require cold atoms, let alone a BEC. Dima Budker and Misha Lukin have done "slow light" experiments using room-temperature vapor cells.

Hau was the only woman to appear in the science segments (IIRC), but I think they would've done much better to replace her with Deborah Jin of JILA, who has done great things with degenerate Fermi systems. Jin's experiments are not only more immediately practical than "slow light"-- they provide some information about the physics of superfluidity and superconductivity-- but they also actually require cold atoms.

The quantum computing bit was fairly content-less, and relied on the "massive parallelism" handwave that drives blogdom's quantum information types up the wall. It could easily have been left out entirely, in favor of spending a little more time on other aspects of the science.

(Also, Seth Lloyd's hair.... Dude. Just... dude.)

(While I'm commenting on superficial fashion issues, Dan Kleppner's vest was sort of an odd decision, making him look like he didnt have any arms in a few shots. On the flip side, they did an excellent job of shooting Eric Cornell in such a way as to hide the fact that he really is missing an arm.)

All in all, it was a very good program. The historical stuff was great, and while I have some quibbles with the more modern material, I doubt there's any treatment of that end of the story that I would find completely satisfactory. It was an excellent introduction to the general subject, and provides some hints of the ways in which ultra-low-energy physics can be every bit as interesting as the high-energy stuff.

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I have to agree. I think they should have showed Doppler laser cooling getting to a milliKelvin and then people finding out you can play around and actually get to a microKelvin with it. (And the brief animation of laser cooling always had the emitted photon going in the same direction, but I'm not going to obsess over that.)

...an excellent job of shooting Eric Cornell in such a way as to hide the fact that he really is missing an arm.

I'm curious why you seem to think that this is a good thing.

I'd hoped that the days of trying to hide this sort of reality were behind us. Example - the baritone Thomas Quasthoff was a "thalidomide baby." Photos on his first recordings (around 1990) were only head shots. But it's been 10 years or so since there's been any attempt to disguise the reality.

By Scott Belyea (not verified) on 16 Jan 2008 #permalink

I know I'm a biologist and I don't even pretend to know what's really going on in cutting-edge physics, but how in the hell did I not know we had created a BEC?! I really have to start taking some time out of my day to read physics articles instead of half-ass skimming them. I was actually embarassed watching the program last night when I found out I was a decade behind on the whole BEC thing.

So: please (please!) use this as an opportunity to explain how laser cooling works. I caught the second half of the show, enjoyed (with comments very much like yours on hair) and planned immediately to come by here and make such a request - and now you gave me a set-up line.

So - please?

[The quantum computer stuff I thought was too hand-wavy by far, and the slow-light was (as when I first heard about it) way way cool but of no obvious use yet. I would have liked a little more on the whole 'why bother?' end of things and also on the nitty-gritty of the science, rather than the people-focussed approach we got. But watching the Kleppner bit made me feel rather better about getting slightly scooped recently - it came across as if his whole *career* had been scooped. Yikes.]

I'm curious why you seem to think that [hiding Eric Cornell's missing arm] is a good thing.

I wasn't saying it was good or bad, it was just noticeable. Mostly because I know Eric-- I'm not sure you would be able to tell otherwise.

I don't know why they did it-- it might've been a production decision, in which case it might not be a good thing, but it might've been in deference to Eric's own preferences. Unlike the Quasthoff situation, he lost his arm only a few years ago, when it was amputated to stop the spread of necrotizing fasciitis (the infamous "flesh-eating bacteria"). It's not a state secret or anything-- it's on Wikipedia, after all-- but he might not want to draw attention to it. In which case, they should respect his wishes.

I wasn't familiar with the cast of characters but I thought it was somewhat obvious that something had happened to Eric's arm between the 2001 Nobel prize and the time of filming - to the point that I googled around for it after I finished watching. I'll admit that I was probably a little distracted while I tried to figure out if it was just a quirk of the camera position.

On the show topic though; did anyone else think the bit with multiple versions of what's-his-face and the whiteboard was just kitchy? His whiteboard explaination was OK until it ended with "and then strange but cool things occur and now we're moving on..."

Complete triva, but I loved that you critiqued the guy's fashions and didn't say anything about the women.

By Larry Lennhoff (not verified) on 16 Jan 2008 #permalink

Chad,
When they explained BEC they basically said "well...this weird thing happens...I dunno how to explain it to you". Am I going to need a degree in physics in order to understand BEC at all?

I did a couple of posts about laser cooling a while back, before the move (part 1, part 2), but I never have gotten around to explaining BEC. It's been on the list of things to do for a while, but it's tricky.

I'll see if I can come up with something this weekend.

Awesome, thanks.

This is kind of a nonsense question, but I'm a layman. If you could have 1 atom floating around in a vacuum (if such a thing could possibly exist), would it have no temperature, regardless of how fast it were moving in the vacuum?