I’ve been all over the world, fortunate that my career in academia has made this possible. Most summers since 1986 I have attended scholarly meetings in other countries, and included extra days (or weeks) in the trip for traveling. Sometimes this has been with friends from the conference; but later I was reluctant for some reason to organize ahead of time, or to ask during the meetings if anyone wanted to travel together. Even some trips that were not related to my work I’ve taken alone. So I’ve eaten many dinners by myself. Probably the best one was in Italy, Florence, at a small restaurant not far from the convent where I was staying. This restaurant had a communal table just for people dining alone – you could converse if you wanted to, or not (what a great idea – typical for the Italians to provide this way of bringing individuals together).
This particular evening, when I sat down there was a somewhat older man in the midst of telling a joke, in Italian, to the waiter or one of the patrons. I don’t speak Italian, but I caught a couple of words of the joke, mathematical terms, “integrale”,”differentiazion”. When he finished the joke, laughing with the listener, I waited a little and then asked if he was a mathematician. He said, no – he was a physicist. The joke, too long to be told here, concerned a mangy but intelligent parrot. I’ve told it many times since then. We spent the rest of the meal in conversation about mathematics, math education and physics. I asked him, near the end of the evening, what he thought was the most difficult unsolved problem in physics. He said “broken symmetry.” I wish I knew enough physics to understand his answer, and I wonder if it’s still unsolved.