Dagstuhl, Wednesday afternoon

The traditional Wednesday afternoon hike took us to a chapel where one could view Dagstuhl from a distance. During the hike Daniel Marx gave me a lightning-speed overview of techniques for FPT algorithms - one example for each algorithmic technique. Now, whenever I see an FPT algorithm, I will remember the sun-filled scenery of green hills, quiet ponds and small streams! David Johnson thinks that, rather than studying this or that more or less artificial theoretical model, our research time would be better spent trying to understand why integer programming works so well. He's had good experiences with it recently. I liked the idea. Neal Young criticized my wish to go back to the Plotkin-Shmoys-Tardos paper and try to understand it: now that I have heard his tutorial, I no longer need to read that paper, he says! (Except for examples of applications). Etc. This is why hiking is such a good thing to do during workshops. The blood flow stimulates the brain, conversation flows easily, and, in a natural environment, informal discussions on topics related to research happen in an organic manner.

The traditional stop of Dagstuhl hikers at a restaurant for coffee and cakes no longer exists. The reception tried to make a reservation for us, but got turned down. Rumor has it that, once, an order of seventy cakes was placed for one group, but nobody showed up at the restaurant. Since then, as the story goes, neighborhood restaurants refuse to take reservations for Dagstuhl people.

I also broke with tradition at meal time: I arrived early, found that Kirk Pruhs and I were going to be seated at the same table for at least the fourth time in a row, and quietly exchanged his name tag with one on the next table. When Kirk arrived, a few minutes later, he took a look at me, at the name tags, and commented: "Not today, eh?"

I have made one convert to tablets: Samir Khuller. He started using his yesterday to take notes during talks (had had it for a while but had never used the tablet features!). Today he asked me how to share a document with other people on the internet, so that we could all edit it at the same time. That would obviously be extremely useful for long-distance collaborations. One would think that that has to exist - the technology is there, there is no reason why that shouldn't be possible. But I don't know.