Post-FOCS post
October 30th, 2009I’m back from the FOCS conference in Atlanta, and since Lance has pointed out the lack of blog posts about it, I thought I would try to say something about it.
For those of you who don’t already know, FOCS is actually the IEEE Symposium on Foundations of Computer Science, and this year marks the 50th annual meeting. This was also my first time to attend FOCS, and it was a slightly odd experience. My background is in theoretical physics rather than theoretical computer science, so I am much more used to the physics model of conferences and publishing.
One thing I found particularly odd is that for such a prestigious conference with a rigorous review process they limited all the talks to 25 minutes including questions. Given the technical nature of many of the results this seems a little strange. Is there really a need to compress the conference into 3 days if it means having such little time to take in each of the results. This also seems to lead to a rather strange style of presenting, where some speakers seem to dive into the technical details without giving the intuition behind their approach. Maybe this is just a cultural difference between CS and physics, but I can’t help thinking that the compact time frame for talks really limited how much I actually took in. There were a lot of very interesting results, and I really wish I had had more time to process these before moving on to a new topic.
The other thing I found strange, being used to physics conferences, was the lack of a conference dinner. I usually enjoy conference dinners as they tend to be a great way to meet other people in the field. While there were lunches on two of the days, these really did seem quite cliquey and so I mostly ended up meeting people who were connected to one of the other quantum speakers (we had our own clique!).
So now I’ve brought up two things I didn’t like about the conference, perhaps I should focus on the things I really did enjoy: the talks. Keep in mind that I have a very different background to most of the attendants, so I am probably skipping over some other great talks. These are simply the ones that caught my imagination.
Day 0 of the conference was last Saturday. It wasn’t part of the conference proper, and was open to the public. There were a series of public talks to mark the 50th anniversary of FOCS and the 20th anniversary of the algorithms, combinatorics and optimization program at Georgia Tech. Even though I ended up staying in the Hotel Palomar (which I thoroughly recommend) right beside the auditorium it took me nearly an hour to find the right place. In retrospect, it shouldn’t have been hard to find at all, except that the map was somewhat inaccurate, and seemed to direct us to a building on the opposite side of the road.
There were four talks in total, from Richard Karp, Mihalis Yannakakis, Noga Alon and Manuel Blum. Unfortunately jet lag got the better of me, and I ended up missing the last talk. Of the first three, I particularly enjoyed Mihalis’s talk on equilibria. Why? Well it seems that many of the equilibria problems he was discussing are of a similar form to the the equations that arise in dealing with closed timelike curves. This probably shouldn’t be surprising, since Deutsch’s consistency condition is effectively just enforcing equilibrium, but none the less I found the connection fascinating. Actually throughout the conference, I found that quite a number of talks dealt with issues that also arise in physics.
Sunday marked the star of the conference, and also the start of parallel sessions. As a result, I was constantly having to decide which session I wanted to attend, and so could only see half of the talks. In the morning I attended session 1B (see the program here), and got a good sampling of talks on complexity. I’ve been interested in a (quantum) communications complexity question for some time, so I particularly enjoyed Paul Beame’s talk on multiparty communications complexity.
By far the highlight of the day for me, though, was session 2A, where we were introduced to the abstract tiling model model by David Doty, before Sandy Irani’s excellent talk on the connection between this problem and Hamiltonian problems in quantum complexity. I really found this session to be eye opening, as I hadn’t been aware of the abstract tiling model before, but it has really caught my interest. Sandy’s talk in particular caught my interest, and I will be reading their paper in detail once I can get my current teaching backlog out of the way.
The other talk that I greatly enjoyed was on polynomial identity testing given by Shubhangi Saraf (particularly the colourful combinatorics!). Unfortunately by this stage I was pretty worn out, and didn’t really take everything in. Another paper for the reading list.
The highlights of day 2 for me were talks by Alexander Sherstov on the intersection of half-spaces and by Vitaly Feldman on statistical query learning.
On Saturday myself and my co-author Elham had flipped a coin to decide who would give our talk, and I lost. On Monday evening we went out to my hotel to finish the slides and have a celebratory dinner to mark our first FOCS paper together. The Palomar, where I was saying, somehow seemed to be both cheaper than the conference hotel and much better. We sat beside a fire pit on the roof terrace, putting the last touches on the slides. Not a bad way to prepare for a talk!
Tuesday was the third and final day of the conference. The quantum session was in the morning, which unfortunately meant quite a low turnout. I have to say, I enjoyed all three of the other talks in the session. Our talk was first, at 9am, followed by André Chailloux talking about quantum coin flipping, then Sarvagya Upadhyay talking about quantum interactive proofs, and finally Ben Reichardt talking about quantum query complexity and span programs.
I found Sarvagya’s talk particularly interesting, but also kind of strange. In his talk he was showing that two message quantum interactive proofs are in PSPACE. This was certainly a major result and I was very interested to hear the details fo the proof. What was strange, however, was that I know the same authors have proved the much stronger result that QIP=IP or equivalently QIP=PSPACE. It is a little strange to sit through what you know to be a talk about a weaker result, when you know the speaker has the stronger result ready to go. Oh well!
Unfortunately, after our session I realised that we could prove another result about interactive proofs, and spent the rest of the day working through the details with Elham, and so missed the later talks.
Despite my reservations about the structure of the conference, I very much enjoyed my first FOCS experience, and I’m hoping that we’ll get the new results written up in time for STOC.













