Miscellany

Entropy in Beantown

I’m in Boston right now, having given an arrow-of-time talk at Tufts this afternoon. No time to blog, as I am obligated to rush around taking advantage of the delights here in the Hub. In particular, no time to follow Majikthise’s suggestion and make a picture of myself as a superhero. (Usually I’m pretty easy to convince on things like that.) But if anyone else wants to take a crack at it, I’d be curious to see how they come out; the best ones that people sent me I will post here. Categories include: superhero avatars of yourselves, of me, or of famous physicists. Villains are also acceptable. (More examples here.)

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Why three dimensions of space just aren’t enough

The second issue of symmetry has just come out. symmetry is a magazine about particle physics and related fields, jointly published by Fermilab and SLAC. It takes the place of their individual house magazines, and looks like a significant upgrade. The editor is David Harris, who hopefully will get back to blogging once things are running smoothly! This issue includes a good article about the status of inflation, including its connection to string theory.

Another interesting little note was the histogram of citations to the original paper by Oskar Klein on the idea of extra dimensions (Kaluza-Klein theory), reproduced at right. The data are from the SPIRES literature database at SLAC, a fanastic service that makes it a cinch to see who cites what papers in high-energy physics and related fields. (Kind of like google scholar, but years ahead of their time.) You can see that there is a peak in the early 80’s, and another one that we’re in the middle of right now. These reflect well-defined movements in high-energy theory. In the early 80’s, the idea of grand unification of the three forces of particle physics (strong, weak, and electromagnetic) had been pretty well investigated, and people were eager to get gravity into the game. In this spirit, KK theory was resurrected, but now in the context of supersymmetry, which has a natural home in eleven dimensions of spacetime.

The movement toward KK theory was squelched by the rise of string theory; the string bandwagon was launched in 1984 when Michael Green and John Schwarz showed that you could cancel certain annoying “anomalies” (quantum-mechanical effects that can destroy classical symmetries), and (almost) everyone dropped 11-dimensional supergravity to work on string theory. Of course, string theory naturally lives in ten dimensions, so the compactification of the extra dimensions is just as important in string theory as it ever was in KK theory; but there are so many other things going on that it made sense to think of strings as a new beginning, and references to the original Kaluza-Klein papers dropped off.

More recently, the string duality revolution showed that there really wasn’t a big difference between ten-dimensional superstring theory and 11-dimensional supergravity; they are each versions of one more comprehensive (and still ill-understood) theory, M-theory. But that’s not the reason for the uptick in citations to Klein in the late Nineties; it’s because of the phenomenological idea of brane worlds and large extra dimensions, led by the papers from Arkani-Hamed, Dimopoulos and Dvali and Randall and Sundrum. These were inspired by work on D-branes in string theory, since it was in that context that people took seriously that we might live on a brane and be unable to escape into the “bulk” in which it was embedded. But the details of string theory aren’t intimately connected to those models (and the idea of being stuck to a brane goes back to earlier work by Rubakov and Shaposhnikov).

The idea that modern theories of quantum gravity imply the existence of extra dimensions was the subject of my talk at the Philosophy of Science Association meeting last month. I’ve finally turned my slides into a pdf file, for anyone who’d like to check them out. Unfortunately the figures didn’t always convert smoothly, so at times you will have to imagine the presence of a string or quark where no image is present. All part of the challenge of modern physics.

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The Weary Blues

By Langston Hughes.

Droning a drowsy syncopated tune,

Rocking back and forth to a mellow croon,

        I heard a Negro play.

Down on Lenox Avenue the other night

By the pale dull pallor of an old gas light

        He did a lazy sway . . .

        He did a lazy sway . . .

To the tune o’ those Weary Blues.

With his ebony hands on each ivory key

He made that poor piano moan with melody.

        O Blues!

Swaying to and fro on his rickety stool

He played that sad raggy tune like a musical fool.

        Sweet Blues!

Coming from a black man’s soul.

        O Blues!

In a deep song voice with a melancholy tone

I heard that Negro sing, that old piano moan–

        “Ain’t got nobody in all this world,

          Ain’t got nobody but ma self.

          I’s gwine to quit ma frownin’

          And put ma troubles on the shelf.”

Thump, thump, thump, went his foot on the floor.

He played a few chords then he sang some more–

        “I got the Weary Blues

          And I can’t be satisfied.

          Got the Weary Blues

          And can’t be satisfied–

          I ain’t happy no mo’

          And I wish that I had died.”

And far into the night he crooned that tune.

The stars went out and so did the moon.

The singer stopped playing and went to bed

While the Weary Blues echoed through his head.

He slept like a rock or a man that’s dead.

You can also listen to the poem read by the author, with music by Leonard Feather.

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Like a prayer

From Bob Park’s What’s New, a newsletter loosely affiliated with the American Physical Society:

PRAYER STUDY: COLUMBIA PROFESSOR REMOVES HIS NAME FROM PAPER. We have been tracking the sordid story of the Columbia prayer study for three years (WN 05 Oct 01). It claimed that women for whom total strangers prayed were twice as likely to become pregnant from in-vitro fertilization as others; it was published in the Journal of Reproductive Medicine. At the time we were unaware of the background of the study, but knew it had to be wrong; the first assumption of science is that events result from natural causes. The lead author, Rugerio Lobo, who at the time was Chair of Obstetrics, now says he had no role in the study. The author who set up the study is doing five years for fraud in a separate case, and his partner hanged himself in jail. Another author left Columbia and isn’t talking. The Journal has never acknowledged any responsibility, and after withdrawing the paper for “scrutiny,” has put it back on the web. Nor has the Journal published letters critical of the study. Columbia has never acknowledged any responsibility. All of this has come out due to the persistence of Bruce Flamm, MD. The science community should flatly refuse all proposals or papers that invoke any supernatural explanation for physical phenomena.

I’m not really sure what it means to say “the first assumption of science is that events result from natural causes,” but we did know that it had to be wrong. This ground was covered a long time ago by David Hume in On Miracles:

The plain consequence is (and it is a general maxim worthy of our attention), `That no testimony is sufficient to establish a miracle, unless the testimony be of such a kind, that its falsehood would be more miraculous, than the fact, which it endeavours to establish; and even in that case there is a mutual destruction of arguments, and the superior only gives us an assurance suitable to that degree of force, which remains, after deducting the inferior.’ When anyone tells me, that he saw a dead man restored to life, I immediately consider with myself, whether it be more probable, that this person should either deceive or be deceived, or that the fact, which he relates, should really have happened. I weigh the one miracle against the other; and according to the superiority, which I discover, I pronounce my decision, and always reject the greater miracle. If the falsehood of his testimony would be more miraculous, than the event which he relates; then, and not till then, can he pretend to command my belief or opinion.

On the other hand, part of me says “who cares?” Certainly in theoretical physics, having published papers that are incorrect doesn’t do any harm; you can just ignore them. Would many readers of the Journal of Reproductive Medicine have their opinions swayed by such a study? Or is it worth fighting to have the paper withdrawn so that it can’t be used for propaganda purposes? Something tells me that, among people who thought the paper was compelling, having it withdrawn would only provide further evidence of their persecution by the Establishment.

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More sexual repression!

In an ongoing effort to reach out to a younger demographic (after the depressing epiphany of last week), Preposterous continues to track the forces of reaction as they attempt to recreate a lost Puritan utopia. In this case, no claim to breaking the news: from Davos Newbies via Pharyngula and Crooked Timber, a story from the Financial Times explains why Americans can’t be trusted to see Veronese frescoes shown on television. Something about naked Cupids. No word on colors or flavors.

For those readers in our older, post-giggling demographic, here’s more traditional fare: NSF budget slashed, via Chris C. Mooney. I guess there’s a fine line between “double the budget” and “cut by $100 million.”

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Sex is fun…

… but we’re not allowed to admit it. At least, not in Illinois, which remains stuck in the Midwest no matter how blue it appears on the map.

It would appear that Governor Blagojevich has decided to stop the Illinois Department of Public Health from handing out free colored and flavored condoms. (Ironically, the announcement was made on World AIDS Day.) Condoms that look and taste ordinary will continue to be handed out as usual.

Apparently the worry is that handing out condoms with color and flavor (just like quarks!) will encourage people to have sex. I cannot quite imagine how these people think a typical pick-up routine might go. “Hey baby, how’d you like to back to my place and have some safe sex? No? What if the prophylactics were … lemon-flavored?”

Allow me to point out what these condoms would actually encourage: using condoms. The campaign on the part of certain people to prevent other people from enjoying sex has been going on as long as we’ve had civilization, and it’s not likely to succeed any time soon. But we can continue to make it safe as well as fun.

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Melba Phillips

This is a couple of weeks late, but still worth noting. Physicist and educator Melba Phillips passed away on November 8th at the age of 97. (Obituaries at the New York Times and Washington Post.) I didn’t know anything about her personally, so everything here is stolen from the press release.

Phillips had a remarkable career. She started on a fast track, as one of J. Robert Oppenheimer’s first graduate students, receiving her Ph.D. from Berkeley in 1935. The Oppenheimer-Phillips effect helped to understand the interactions of deuterons with other nuclei. But jobs were scarce during the Depression, and being female didn’t make it any easier. She finally landed a faculty position at Brooklyn College in 1938. She had a strong social conscience and was politically active, helping to found the Federation of American Scientists in 1945. Her activities got her in trouble in the McCarthy era, and she ended up being fired in 1952 after refusing to testify before a U.S. Senate committee investigating alleged communist activities. Much like the Pope and Galileo, Brooklyn College eventually apologized somewhat late, in 1987; they held a symposium in her honor in 1997.

Unemployed, Phillips turned her attention to physics education; her book with Panofsky is till a standard text in undergraduate electromagnetism. From 1966 to 1967 she served as president of the American Association of Physics Teachers, which later created the Melba Newell Phillips Award in her honor.

She joined the faculty of the University of Chicago in 1962, recruited by her former student Stuart Rice. Among other accomplishments, she was responsible for the first physics course taught here to non-scientists. She retired in 1972, but remained active, serving as a visiting professor at several universities. A rich and admirable life.

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Sentences you won’t hear me say very often

“Here’s a very nice post at the Volokh Conspiracy consisting almost entirely of a quote from George Will.”

The filibuster is an important defense of minority rights, enabling democratic government to measure and respect not merely numbers but also intensity in public controversies. Filibusters enable intense minorities to slow the governmental juggernaut. Conservatives, who do not think government is sufficiently inhibited, should cherish this blocking mechanism. And someone should puncture Republicans’ current triumphalism by reminding them that someday they will again be in the minority.

In case you might be tempted to give too much credit to Will for his sensible level-headedness, check Brian Leiter on academic diversity.

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A reason to join the American Astronomical Society

Finally a good motivation for joining the AAS — Robert Kirshner‘s “President’s Column” in the monthly newsletter. The newsletter is only available to AAS members, since we wouldn’t want all the secret goodies in there leaking out to the unwashed masses. Normally this is no great loss. But since Kirshner has become president, the monthly column has become a highlight.

Here at Preposterous we toil thanklessly for the greater good, so we might just make it a regular feature to excerpt some of Bob’s best quotes. Last month the topic was the process by which NASA decides to make the wrong choices (as revisited in Risa’s last post). This month it’s about the connection between astronomy and physics. Here are the opening few paragraphs:

Everybody has this happen to them — you’re sitting on an airplane, headed for the AAS meeting or an observing run or a windowless room at NASA headquarters when a stranger sits down in the seat next to you. You’re revising a manuscript (changing “affect” to “effect” or the other way around), or writing a referee report (“this paper contains too few references to the pioneering work of the anonymous referee”), or browsing through the AJ (“this paper is pretty good, I wonder if I’m a co-author.”) The person next to you, picking up on these subtle cues, asks, “What do you do?” Here you must make a quick judgment. Do you want to talk to this person?

If your answer is yes, then you say, “I’m an astronomer” and you can be sure your neighbor will pick up that thread — possibly asking for a personal horoscope, possibly asking you for insider information on that satellite that landed so firmly in Utah, and possibly asking if the dark energy is really the cosmological constant. In any case, both time and the airplane will fly.

On the other hand, if the idea of talking to this stranger (“outreach” in NSF-speak) is less appealing than having three hours of root canal work, you just say, “I’m a physicist.” Somehow, that always produces a social retreat, leaving you in your own cocoon of noise-cancellation to compose letters of recommendation that skirt the inside edge of perjury.

Well, the rest is just as good, but I’d hate to have the notorious AAS lawyers come after me. (I’ll have to encourage Bob to start up his own blog, perhaps once this AAS presidency is over.) The point is that there is not a sharp line telling us where astronomy ends and physics takes over, or vice-versa. Some of the most important questions at the heart of each discipline are right there in the heart of the other — biologically difficult to manage, but metaphorically quite manageable.

Of course such a claim sounds so cliched and feel-good as to almost not be worth mentioning on a cutting-edge blog such as this one. However, it remains true that the categories of “astronomy” and “physics” are quite reified in the worlds of funding agencies and university departments, and this can often be a source of trouble. If I were a gossip, I could tell many stories of visiting places on my job searches and being asked, “Sure, we know you dabble in gravity, and astrophysics, and field theory — but what are you really?” One of the nice things about the University of Chicago is that the barriers between the fields are remarkably low, but other places aren’t so lucky. At Harvard, where Bob Kirshner was the department chair when the Astronomy Department grudgingly awarded me a Ph.D. for work on “Cosmological Consequences of Topological and Geometric Phenomena in Field Theories,” there is a fifteen-minute walk through the snow to get from the Physics Department to the Observatory, and it’s not a very beaten path. They’re making an effort, though, so I wish them luck.

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Smorgasbord

Scandinavia seems like such a peaceful place. Maybe they got all the lust for violence out of their system with the whole Viking thing; or maybe it’s still there, just bubbling below the surface, invisible to an outsider like me.

Returning to reality, and taking a quick tour around the news and the blogs, uncovers too many sad stories and reasons for disgust to really keep track of. Here’s a little list, so you can choose to target your outrage according to your geo-political predilections.

No claim is made to being exhaustive.

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