Thursday, May 7, 2009

Leiden EasyMeeting

This week I slipped off to the Netherlands for the yearly meeting of the UK/Netherlands quantum matter community. Held in Leiden, just a quick train ride from Amsterdam Schiphol airport, and named easyMeeting (for reasons that are still not clear to me) the two-day meeting was supposed to put the two analogous communities in the UK and the Netherlands in better contact with each other.

Many of the talks were interesting (more on these below). The Lorentz center where it was held is extremely well organized. The Hotel was fine, and the conference dinner was excellent – including a fair amount of wine and a dangerous Dutch concoction known as jenever (which lives somewhere between vodka and gin). Jan Zaanen seemed to be encouraging everyone to pop across the street to the coffee shop where they have the cheapest marijuana in the city. (I don’t think anyone partook… physicists are a pretty straight-laced bunch).

[Physics gossip: After a few glasses of wine, people always start gabbing. Among other key pieces of info I extracted was to find out who is being considered for the Lucasian chair at Cambridge – the professorship that Stephen Hawking currently holds (he is retiring this year). This position has also been held by Isaac Newton, and Dirac, among others. I probably should not post the information publicly, but if you are curious and want to engage in rumor mongering, feel free to give me a call and I’ll spill.]

A few of the things I really liked from this meeting:

The most interesting talk to me was given by Darius Sadri on the topic of AdS/CFT – that stands for Anti-de-Sitter/Conformal Field Theory. This is a technique invented by the string-theory community that draws a connection between quantum physics of scale invariant systems in d+1 dimensions and classical gravitation in d+2 dimensions. The idea has been around for about a decade, but only very recently has it found applications in the condensed matter physics community where it can be used to describe certain quantum phase transitions (which are inherently scale invariant). This mapping gives a way to understand certain “nonperturbative” systems that would be completely intractable otherwise. I confess, however, that I do not understand much about the details of the technique at this point. It seems that many of the mappings are imprecise at this point, and the only cases that have really been worked out in depth are not of interest to condensed matter physics (the canonical case being large N supersymmetric N=4 gauge theory [The two N’s in this sentence are different variables, sorry about that]). But the idea of applying this technique to “real” condensed matter systems seems to be rapidly gaining steam in the string theory community and in the condensed matter theory (CMT) community as well. See also this posting by Motl on how this field is developing. Next month there is going to be a short workshop at KITP on AdS/CMT – that’s a pun, for those keeping track. I’m told that it is going to be heavily attended by string theorists, but they are having a hard time getting CM theorists to show up.

Other interesting talks from this meeting:

Mark Golden (a Brit transplanted to UvA – university von Amsterdam, not Virginia) gave a very nice talk about various ARPES-type scattering experiments on the pnictides (I blogged about pnictides earlier here).

Johnathan Keeling from Cambridge gave a nice discussion of condensation of microcavity polaritons – a field that I’ve been following tangentially for some time, but I’ve never actually worked in the field (although I had various forays into the related field of exciton physics, see here and a series of papers thereafter).

Nigel Hussey from Bristol gave a nice discussion of transport experiments in the cuprate high temperature superconductors (it is amazing that after 20 years now, there is still interesting new data).

My old friend Andrew Green, now at St. Andrews, gave a very nice discussion of some progress on quantum criticality in various magnetic systems.

Kareljan Schoutens and I both gave talks on topological phases of matter, although from very different perspectives.

There were a bunch of other good talks too, but these were the ones that stood out in my mind. These, and the jenever.

PS: This blog entry was posted entirely from the Heathrow-Oxford bus. How cool is that?


T said...

But would've been even cooler if it wasn't about physics. Just kidding.

Steve said...

In my defense, I did mention both jenever and marijuana in this posting too.

Nuntiya said...

Jenever, by the way, is the "original" gin. Gin is the anglicized name for it.

Steve said...

As Johnny Carson used to say "I did not know that".

but it does indeed seem to be true!