I was already worried when he asked for his dinner in one hand while he still had his computer open on his dinner table. It was a full flight and he was a big guy. I had my newly arrived dinner, with my water and orange juice, in front of me. Somehow he managed to put away his computer with one hand while balancing his dinner in the other. I relaxed in relief, just in time to see him turn and swat my orange juice into my lap.
I was on my way to a math conference in Granada, Spain. I have lots of friends in Granada, including my collaborators on the Double Bubble Theorem, my only paper to appear in Annals of Math. One summer I'd even taken my four undergraduate research students to Granada for nine weeks. It was helpful that one of them, Alex Díaz, was from Puerto Rico, with language skills of special use when they got in trouble. While I was away for a few days giving some talks in Italy, they made their way to Pamplona for the annual running of the bulls. They assured me they would watch from a distant mountaintop. So I had something of a shock when I saw some of the exciting footage. As the crowd rushed down the main street, there they were, leaping out of the path of the charging bulls. Alex is behind red-shirt on the left, while Sean is in the lower right corner.
Fortunately they made it back to Granada in one piece, although Sean had his wallet and passport stolen in the train station.
But most of the time they did math in their rooms, and they proved some nice results. Alex summed it up like this:
Alex Díaz concludes, "We found the perfect combination: isoperimetric problems, Granada, and us."
So it was fun to see familiar places and friends on my return this week. The conference boasted talks by leading theorists and experimentalists. The three local organizers were my old friends Rafa López and Paco Martín and Antonio Ros.
Here Ros, an illustrious theoretician, describes in five words why he likes such conferences:
One excellent talk was by a University of Delaware graduate student, Nicholas Brubaker. In 2007, he had worked on a research project I suggested along with other undergraduate students of Ron Umble at Millersville University. They studied soap bubbles in a cube. Previously a graduate student team at a summer school at the Mathematical Sciences Research Institute in Berkeley, California, had computed candidate double bubbles:
From Carrión et al., used by permission.
Nick and his collaborators managed to reproduce the candidates physically, thus demonstrating their physical stability. Here are their "center bubble" and "slab cylinder":
"Center bubble" and "slab cylinder" from Brubaker et al., used by permission.
Here, Nick tells about creating these soap bubbles: