Archive for August, 2010

ICM2010 — rest of day three

August 31, 2010

At some point earlier in the day — I forget exactly when — Oliver Riordan asked me whether I was going to a reception hosted by the British Council and EPSRC (the Engineering and Physical Sciences Research Council — an administrative body that decides how quite a bit of Britain’s science budget is spent). I had had an email invitation in the morning and not got round to replying to it, but Oliver said he was going over to an EPSRC stall in the large room where various publishers and other organizations had stalls, and would be happy to tell them I was coming, which they needed to know because it involved taking us to a hotel in the centre of town by bus. I thought, “Well, if Oliver’s going then I may as well go,” which turned out to be a good decision.

Also happening that evening was a performance of A Disappearing Number, a play by Théatre de Complicité, a British theatre company directed by, and co-founded by, Simon McBurney. If that name means nothing to you, you may still remember a seedy British diplomat in the film The Last King of Scotland. He was, or rather played, that diplomat. The play is partly about the Hardy-Ramanujan story, and has had several runs in Britain over the last two or three years, to great acclaim. Despite knowing Simon (about which more later) I had not got round to seeing it, but neither had I got round to getting a ticket for today’s performance while they were still available — which was OK because the play was on in Hyderabad both today and tomorrow.

ICM2010 — Spielman, Csornyei, Lurie

August 31, 2010

I’ll begin this with a question: why is it that theoretical computer scientists are, on average, far better than other mathematicians at giving general-audience talks? Irit Dinur’s plenary lecture at the ICM was, as I have already said, excellent, but that kind of excellence seems to be the norm for theoretical computer scientists: I basically know, when I go to the TCS plenary lecture at an ICM, that I’m in for a treat. (But that is not the whole story at all. For example, I also know that if I’m at an additive combinatorics conference at which Ryan O’Donnell is speaking, then again I am guaranteed an extremely interesting, entertaining and comprehensible talk.)

Even by the exalted standards of theoretical computer scientists, Spielman’s talk was masterful. (If you’ve been reading all these posts, you may remember that I predicted this after hearing him answer a question at the post-opening-ceremony press conference. Well, my prediction was not just correct but hypercorrect.) He started by thanking all sorts of people who had inspired him to become a theoretical computer scientist, and even this he made interesting and amusing — for instance, he showed us a picture of one person, a high-school teacher or something, and ended a brief discussion of that person by saying, “And he was the one who made me want to become a mathematician.” And then after the next person he said, “And he was the one who made me want to become a computer scientist.” And at the end of the talk he somehow (in a way that I’ve now forgotten) brought the whole thing full circle and reminded us of these initial remarks about his early intellectual life.

During the talk, he marched about the stage, always talking to us, the audience, and never to his slides — it was as though he knew from memory what was in them, though there was something on the stage (other than the lectern) that may have been a display for the benefit of the speakers. I never quite got round to checking.

ICM2010 — Avila, Dinur, plenary lectures

August 30, 2010

I dragged myself out of bed on the third day feeling pretty terrible — in fact, terrible enough to be slightly worried that I would be doing myself some damage with this succession of short nights, which I couldn’t see how to do anything about, given the necessity of starting early (a result of the schedulers’ evil decision to put superstars and known excellent speakers on in the first slot of the day). But nothing much distinguishes the beginning of the third day from the beginnings of the two previous days, so let me jump to the first talk, Artur Avila’s plenary lecture.

But before I do so, I have remembered one small thing that did make this day slightly different. In order to put on the unpleasant insect repellent, I took off my name badge, and then I forgot to put it back on again. I realized what I had done just as the bus was pulling out of the hotel. I wondered whether it was worth delaying the bus for three minutes while I dashed to my room and back, but Irit Dinur, who was in the same bus (I had not previously realized she was even at the same hotel, because she took a much more relaxed attitude than I did about getting up for the first talk — the previous day she’d watched the streaming video from the hotel instead), told me that she had forgotten hers yesterday, and the only consequence was that she had had to go and ask for a replacement. Well, that wasn’t quite the only consequence — the replacement badge no longer said, “Invited Speaker” on it, and she did not get a new set of coupons for lunch and coffee.

I decided I could handle walking around as a mere delegate, and could even handle not having a lunch coupon, though that was slightly disappointing. But for some reason when I asked for my replacement badge it was an exact replica of the original one and it did come with the coupons. (So in theory I could have had seconds for lunch the next day — but in fact I ended up not even having firsts.)

Artur Avila is young (we were told that he was this ICM’s youngest plenary speaker) and strikingly handsome in a black polo shirt and dark jeans, as this photo demonstrates rather inadequately.
Etienne Ghys and Artur Avila just before Avila's plenary lecture

ICM2010 — rest of second day

August 26, 2010

[Update: this post is now complete.]

On my way to the ICM I bought my first ever digital camera. From the quality of the photo below, you may not be surprised to hear that it is my first, though actually I have taken some good photos with my wife’s — I just couldn’t seem to get mine to take decent photos in the windowless main hall of the convention centre, which was not very light but had screens that were lit in a way that made the rest of one’s photos come out dark. Also, I took this photo from a distance that meant that even with the zoom on full I had to crop it quite a bit to get what you see below. But that’s enough excuses — I also want to celebrate the first ever illustrated post on this blog. The picture shows Smirnov and Kesten just before the first of five talks given by a new Fields medallist or Nevanlinna prizewinner: Smirnov to give the talk and Kesten to introduce it.

Smirnov and Kesten just before Smirnov's talk

ICM2010 — Nirenberg and Meyer laudationes

August 25, 2010

Normally at an ICM the first day has its own very distinct atmosphere because of the opening ceremony, the laudationes, and so on, after which the congress settles into a more regular, working format, with plenary lectures in the morning and invited lectures in parallel sessions in the afternoon. This year, because the number of prizes has increased and one of them needed inaugurating, some of the first-day feeling continued into the second day. And because my panel discussion was in the afternoon and lasted two hours, I had to miss the parallel sessions, so I personally had no sense of the ICM having properly started until the third day.

ICM2010 — Chern prize inauguration

August 24, 2010

Yesterday I wrote a post in the Rajiv Gandhi International Airport in Hyderabad. I couldn’t post it there because I wasn’t connected, but Dubai airport had free wi-fi so I could finish the job a few hours later. The ICM interrupted a holiday I was having in the South of France with my wife’s family, so now, after a refreshing four-hour night, I find myself at 6.30am in the rather less glamorous Luton airport, stupidly early for a flight on a rather less glamorous airline than Emirates, with whom I flew to Hyderabad and back. Talking of stupid punctuality, there’s a maxim I quite like, which is probably very well known but I heard it only within the last year or two, which is that if you have never missed a plane then you spend too much of your life in airports. I like the maxim, but I don’t live by it, because I have an irrational dread of missing planes, and an entirely rational lack of dread of spending time in airports — if all else fails, they are a pretty good place to do mathematics. Today, all else has not failed, since I have a charged up computer (that’s an issue these days — I think my laptop is due a new battery) and multiple blog posts to write. I haven’t quite decided what form these will take: I cannot possibly write about days 2-4 in the same amount of detail as I have written about day 1, but once I start, it is hard to stop. So do I prefer to keep up the detail and risk stopping in the middle of day 2, or to force myself to become a bit sketchier? Perhaps I’ll be detailed, but more selective about what I write about.

ICM2010 — rest of day one

August 23, 2010

As I write this I'm sitting in the Rajiv Gandhi international Aiport waiting for a flight to Dubai. The ICM lasts till Friday, but for me it is over: with a son of two and a half, there are limits to how long it is reasonable to be away, and the marginal utility of the ICM has dipped below the marginal cost of staying away (or rather, that is how I judged it in advance). Actually, today (Monday the 23rd) is the half-way point and is a free day. Most of the delegates, to judge from the people I've spoken to, are taking the opportunity to go on ICM-organized tours. It is pretty tantalizing not to be doing that myself, but I leave India with a huge affection for the country and a strong sense that I'll be back.

Listening to five laudationes in a row is pretty gruelling — as I know from having done it five times now. After they were over, Assaf Naor asked whether I wanted to go and get a cup of coffee somewhere, or whether I would be listening to the talk by Varadhan, a recent Abel prize winner. To make my decision easier, he explained that he himself was skipping the talk only because he had heard it before, and he knew that it was excellent. I hesitated, and in the end decided that self-preservation was in order, a principle that I continued to adopt later. By that I mean that if you go to every talk that has a good chance of being superb, plus every talk that is sufficiently noteworthy that you don't want to miss it even if it is terrible, then you end up utterly exhausted. Because the laudationes had started late, there was very little break between them and the beginning of Varadhan's talk, and I just couldn't face three and half hours, or whatever it would have been, of continuous talk. The difference between this ICM and previous ICMs is that these little decisions of mine, which I normally like to make rather discreetly (which is particularly easy for parallel sessions, because you might always be at a different talk), are now completely public. But I think I'm ready to live with this.

ICM2010 — Spielman laudatio

August 22, 2010

I’ve saved the best till last, which should not be taken as a negative comment about the other laudationes, since Gil Kalai’s was a tour de force. His first distinction was that he was the only one of the five speakers not to be wearing a tie. He was, however, wearing a suit, so the result was to look smart in a trendy way rather than smart in a more standard mathematician-giving-important-talk way. And he opened his talk daringly with the promise that his would be a comprehensible talk, which got a laugh from the audience.

On a more negative note, I was a bit shocked that a significant proportion of the audience got up to leave before he started, as if to say, “The real business is over — this is just the Nevanlinna prize.” All I can say is that it was their loss, not just because of the wonderful talk but also because of the wonderful mathematics described in the talk.

ICM2010 — Villani laudatio

August 22, 2010

The first thing that stood out when H-T Yau got up on to the stage was his relative youth. (I’ve just looked him up and he was born in 1959.) He began with an amusing quote from von Neumann, who advised Shannon to use the word “entropy” on the grounds that “Nobody knows what entropy really is, so in a debate you will always have the advantage.” Part of the reason von Neumann said that was that there has always been a tension between the irreversible nature of entropy and the reversibility of the Newtonian mechanics that is supposed to underpin it. How can the two be reconciled? My impression is that this quasi-philosophical problem has largely been sorted out (so in particular, I’m not about to say that Villani has “solved the mystery of entropy” or something like that). In fact, let me reproduce Yau’s list of Villani’s three major achievements.

1. He established a rigorous connection between entropy and entropy production. (I don’t actually quite know what he meant by this.)

2. He established entropy as a fundamental tool in optimal transport, and curvature in metric spaces.

3. He rigorously proved a phenomenon known as Landau damping, a very surprising decay of the electric field in a plasma without particle collisions (and therefore without entropy increase).

I’ve just looked at Tao’s post on the Fields medallists and my understanding is such that I’m not even quite certain which of the above three achievements he is describing in detail. (That’s a comment about the headings — Tao writes with his usual clarity.)

ICM2010 — Smirnov laudatio

August 22, 2010

Next, Kesten shuffled on to the stage. He has an unusual face, in that he has a white beard of the kind that looks as though it is never trimmed — indeed, I think that is probably the case, given the way it grows out sideways as well as down — and looks slightly fake, to the point where one cannot help imagining what he would look like without it, to which the answer is that he would probably look a lot younger as the hair on the top of his head is black. (As I write this, in a large room with dozens of terminals, he has just walked in.)

He began by telling us that Smirnov had got perfect scores in the International Mathematical Olympiads in 1986 and 1987, just in case we were in any doubt about his mathematical talents. His next remark came as a very pleasant surprise: even since the committee had made its decision — in fact, in the last two months — Smirnov had proved a major result. Let me begin by saying what that was.