Preposterous Universe

 
La Ville Lumière

One of my great regrets is that I have never learned to speak French. Just about every year I resolve that I'll finally bite the bullet, I buy a new book or set of CD's, and for a couple of weeks I make an honest effort, before being distracted by the rest of my life. So I can ask for coffee, and say "Je regrette, mademoiselle, mais je ne parle pas Francais," but that's about it.

I'm sure I would appreciate Paris much more if I spoke the language, but it's still one of my favorite places to spend time. I've been here often enough that I feel absolutely no obligation to zoom around experiencing all the standard tourist fare -- I've been to the museums and the churches, now I can just relax and enjoy the city. Of course, I'm not an energetic tourist by nature. There is a tour group staying in my hotel, and their schedules are posted by the elevator -- "7:15 Wake up. 8:15 catch bus to Giverny." People actually pay to fly around the world just so they can be catching a bus at 8:15?

For me, Paris is about wandering the streets randomly, peeking into art galleries and stopping frequently at cafes, biding time in between meals. Unless it's a special occasion and you want to be fancy, there's no point in planning ahead of time what restaurant you'd like to go to; as far as I can tell every street of Paris has about twenty restaurants per block (okay, a slight exaggeration), and part of the fun is stumbling across something unexpected. The best such experience I've had was with a couple of friends several years ago, when we cautiously entered a tiny establishment that looked almost cave-like with its white stucco walls. The proprietor, as it turns out, was also the piano player, and he became increasingly gregarious through the evening as he worked his way through a bottle or two of wine. He was quite the polyglot, and between songs he would sit at the tables of his customers and boast that he could converse with any of them in their native tongues. One of my friends was Finnish, so we stymied him. I have no recollection of the food, but the dinner was fantastic. Not that the cuisine is generally to be forgotten; last night I had a crepe with pate of foie gras and caramelized apples that I'll remember for quite some time.

The perfection of cafe lifestyle is Paris's finest achievement, not to mention Chicago's greatest failure. (Even compared to the coasts, Chicago's cafe scene is abysmal; it's dominated by Starbucks, and the few remaining stragglers are generally too crowded or noisy to be comfortable.) How wonderful is it to be in a city with a choice of cafes on every corner, where one can sit inside or outside, linger indefinitely over a coffee or a glass of wine, and order food or not as one chooses. Of course I am fortunate enough that such behavior can actually qualify as work. Not only is it possible for me to bring along some papers and a notepad and happily scribble the equations that are a theoretical physicist's stock in trade, I'm much more efficient in such surroundings than I am in my actual office.

Not that my visit is all patisserie and cafe au lait, goodness no. Last week I was attending a conference at the Institute d'Astrophysique de Paris on Mass Profiles and Shapes of Cosmological Structures. This may come as some surprise, as I know nothing of any interest about the mass profiles nor the shapes of cosmological structures. However, the organizers wanted to have a substantial discussion about whether dark matter could possibly be replaced by modified gravity. Although I haven't worked on that problem directly (I've tried to replace dark energy, but never dark matter -- please, I have my standards), I was able to give a mostly-competent review from the perspective of an interested outsider, to help negotiate between the skeptical astronomers and the other gung-ho modified-gravity theorists they had invited (including Milgrom himself).

And now this week I'm at the Service de Physique Theorique at Saclay, a 20-minute train ride south of Paris. I'm visiting Geraldine Servant, a former Chicago postdoc and now faculty at Saclay and expectant mother. (Christophe Grojean, at left in the picture, is the expectant father -- congratulations to both of them!) We are working with some other friends on how to make dark energy at particle accelerators. Tentative answer: it's hard to do. But you knew that already.

~ posted by Sean Carroll at 5:10 AM ~ link ~ ~ ~