Looks like American soldiers are once again allowed to walk around London, after a brief period in which they were forbidden to do so right after the bombings. No such luck for the physicists here at Saclay — word has come down from on high that nobody is allowed to travel to England for the time being, presumably out of fear of further attacks. This is quite a disruption, as the big SUSY 2005 conference is being held in Durham next week.

Any counter-terrorism experts out there are welcome to correct me, but this strategy seems exactly wrong. I would guess that the time right after an attack is the absolutely safest time to travel. Surely, everyone riding a bus or the Tube in London is going to be just as jumpy and suspicious in the weeks to come as Americans taking airplanes were after September 11. Not only would it be much harder to carry off an attack, but the terrorists undoubtedly know this themselves, and it seems unlikely that they would even try.

I won’t even bother to point out that, even including the successful attacks that have already occurred, the likelihood of being killed by terrorists is completely negligible compared to more mundane forms of danger. Death by subway bombing is so dramatic and horrible that it’s hard not to worry about it far out of proportion to the actual threat (much like comparing sharks to vending machines). So some bureaucrats in Paris (or wherever) will feel assured that they are doing their job if they prohibit scientists from traveling to Britain. After some time passes, they will decide that the danger has diminished, and we can resume talking about important things, like the predicted abundance of neutralino dark matter candidates in various supersymmetric extensions of the Standard Model.

Sad times for Chicagoans and public-radio lovers everywhere: Odyssey, the noontime “talk show of ideas” on Chicago Public Radio, has been cancelled by the WBEZ board. Despite being syndicated to over 30 stations nationally, the show was judged to not quite be worth the cost.

This is a huge loss, as Odyssey was some of the most intelligent and stimulating conversation you could find on any sorts of airwaves. I admit that I’m biased: I’ve appeared on the show myself, and host Gretchen Helfrich was even a guest-blogger here at Preposterous. But just because I’m biased doesn’t mean I’m not right. The show offered serious and substantive discussion about intriguing issues with top-flight experts, often academics who were stars in their fields — a serious intellectual consideration of difficult ideas, not the kind of Crossfire-style empty babbling that Jon Stewart skewered so effectively. Consider some of the topics considered just in the last couple of weeks:

• Founding America: Beyond The Fathers
• Religious Meanings of the Ten Commandments
• The Social History of Computers
• Domesticating the American Man
• Torture and Democracy
• Identity Politics

Hell, they even had a show about blogging. Okay, but other than that, we’re talking about some really substantive discourse here.

Josh Andrews, senior producer of Odyssey, recently started blogging at The American Sector, where he talked a little about the shock of this decision. Here’s hoping that he and Gretchen and everyone at the show land on their feet — the airwaves will be a lot poorer without them.

Update: More comments from Henry Farrell at Crooked Timber. If you’d like to complain to WBEZ, write to Torey Malatia:

Torey Malatia
General Manager, WBEZ
848 E. Grand
Chicago IL 60611
312-832-3312
tmalatia@wbez.org

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.

When I arrived in Paris, I was hoping to zip quickly through customs, as I hadn’t checked any baggage. But there was a huge line at passport control, for which the explanation was readily apparent: there wasn’t anyone manning the booths, so nobody was going through. We stood for a while in line, quietly grumbling. Suddenly there was a muffled bang that startled the waiting travelers; over a railing we could see security officers dealing with some sort of equipment. Had they just set off a controlled explosion of a suspicious-looking parcel? I have no idea, but officials soon appeared at the passport control booths and we began to move expeditiously through the checkpoints, fanning out to escape the airport.

It’s not so easy to forget the possibility of a terrorist attack here — there are no ordinary metal trash cans on the streets, just transparent green plastic bags hanging from metal hoops. The preference for plastic bags over metal cans goes back to the series of subway attacks in Paris in the mid-Nineties. Even though I’m sure that car crashes (or scooter accidents, in this city) are statistically a much greater threat to one’s health, the constant reminders of more horrific possibilities must exact quite a psychic toll.

Now London has been attacked in a series of bombings. The explosions targeted the public-transportation system at the height of rush hour — clearly designed to kill and hurt the largest possible number of people. The city is used to terrorism, having dealt with the IRA for so many years, except that you never really get used to it. I wonder if the culprits have any feeling whatsoever that their actions will really help redress whatever wrongs they perceive, or whether they act out of simple mindless rage?

London will host the 2012 Olympic Games. All I can say is, thank goodness New York didn’t win. One of the things I noticed here in Paris this week was how much people really did care about hosting the Olympics — it was all people were talking about. I teased them by saying that Hillary Clinton was going to bring it to NYC, but they seemed (correctly, in retrospect) much more worried about that suspicious Tony Blair. Not that I have much actual data, but my feeling is that people on the street in New York weren’t really worked up about this, no? But in Paris this is their third serious bid in recent years (1992 and 2008), and they haven’t hosted since 1924, so this defeat means that it’ll be a long time before the French have any enthusiasm for trying again.

One of the things in London’s favor was, paradoxically, that there would actually need to be a greater effort to get the city in shape for the Olympics. As a result, the Games would leave a greater legacy on the city itself — the East End would undergo a relatively substantial transformation. This might even be true, if my impression is correct about the improvements that Atlanta witnessed when they hosted the Games. But still, I’m surprised that people care so much about this. It’s not like it’s the World Cup or anything.

I mostly slept through Independence Day, and so missed the celebratory fireworks from smashing into another celestial body (Matt McIrvin points to pictures here, here, here, here, and PZ Myers links to movies). For the next two weeks I’m in Paris, which (according to some myths) liberty was invented a couple of centuries ago, and (according to others) it now comes to die. Whatever, the croissants are excellent.

In honor of our freedom, here’s a reminder of the dangers we face, from Brian Leiter.

Herewith Newt Gingrich (as reported by The National Review), former Speaker of the U.S. House of Representatives, and still prominent spokesman of the American right (which now runs the country, in case you forgot):

We ought to say to [state university] campuses, it’s over…We should say to state legislatures, why are you making us pay for this? Boards of regents are artificial constructs of state law. Tenure is an artificial social construct. Tenure did not exist before the twentieth century, and we had free speech before then. You could introduce a bill that says, proof that you’re anti-American is grounds for dismissal.

Why stop there? Why not “proof that you didn’t vote for George W. Bush is grounds for dismissal”? Or how about “proof that you don’t believe in God,” since that’s tantamount to being anti-American anyway? Such a law is obviously unconstitutional, but this apparently didn’t bother Herr Gingrich.

“Proof that you’re anti-American is grounds for dismissal” is such a perfectly anti-American sentiment that I’m surprised Gingrich’s head didn’t explode. Of course, I suspect that his head is made of animatronic plastic and that he’s controlled by radio signals sent from an undisclosed location, but that’s just me.

Here I am, a fully credentialed professional scientist, and I get my cool science tips from BlondeSense. I did know that the NASA probe Deep Impact is scheduled to collide with the comet Tempel 1 early in the morning of July 4th (or late at night on the 3rd, depending on your local time zone). But I didn’t know there’d be a webcast. Don’t expect smooth high-resolution video, but you can get images updated every 45 seconds from Kitt Peak, or watch NASA TV.

I won’t be watching in real time, as I’ll be winging my way over the Atlantic Ocean from Chicago to Paris at the moment of collision, about 12:52 a.m. Central Time on July 4th. You feel sorry for me, I know.

By the way, are the folks at NASA public-relations geniuses, or what? Not only do they schedule the impact for Independence Day, but they’ve made a CD with the names of 650,000 people who signed up for the Send Your Name to a Comet campaign. A copy of the CD is on the spacecraft, and will smash into the comet along with the rest of it. Brilliant. If only they would use their powers for good.

Josh Faber, an astrophysics postdoc at Urbana-Champaign, is looking for ideas. He is working with the Orpheum Children’s Science Museum on projects for an upcoming Einstein day to be held in the fall. They are looking for ideas for hands-on demonstrations that would help teach young kids about various ideas from Einstein’s work (relativity, photoelectric effect, whatever). The idea, as I understand it, is that they are really looking for demonstrations, not just some paragraphs of text. I think that being metaphorical is okay (such as the old chestnut of a curved rubber sheet to represent curved spacetime), but the underlying scientific concepts should be correct.

Leave suggestions in the comments. Let’s see if anyone can come up with anything that makes it into the museum.

Remember when we talked about Chief Illiniwek, the University of Illinois mascot? The Chief’s supporters claim that it’s really a gesture of respect to have a student dress up in war paint and do silly dances — a matter of honoring the bravery of Native Americans. Notice any similarity to the explanations coming from Mexico these days?

The new issue of symmetry magazine has hit the virtual newsstands (and the real newsstands, for all I know). Much good stuff as usual, including a deconstruction of the CMS experiment at CERN that I mentioned a few weeks ago. There is also an interview with new Fermilab director Pier Oddone, who quotes with approval the motto of Chicago architect and planner Daniel Burnham: “Make no little plans; they have no magic to stir men’s blood.” Apparently the 21st-century realization of this advice is to build a linear collider.

There is also a tiny contribution by me: extra dimensions in 60 seconds. Okay, so I had to gloss over some details. Even better, you can learn that Alan Guth’s real claim to fame is not that “inflation” stuff — it’s that he is the only person to have written papers with both me and Lisa Randall.