Cat massages dog, from Hedonistica.

The winners of the Gravity Research Foundation essay competition have been announced. (And if you’re wondering how they did it so quickly, the deadline was actually the end of March.) Links where I could find them.

Gravity Research Foundation
PO Box 81389
Wellesley Hills, MA 02481-0004

Roger W. Babson, Founder
George M. Rideout, Jr., President

The trustees are pleased to announce the Awards for Essays for 2005.

1.$3,500 The String Coupling Accelerates the Expansion of the Universe, by John Ellis*, Nikolaos E. Mavromatos+, and Dimitri V. Nanopoulos#; *TH Division, Physics Department, CERN, CH-1211 Geneva 23, Switzerland; +Theoretical Physics, Physics Department, King=E2=80=99s College London, Strand WC2R 2LS, UK; #George P. and Cynthia W. Mitchell Institute for Fundamental Physics, Texas A&M University, College Station, TX 77843, Astroparticle Physics Group, (HARC), Mitchell Campus, Woodlands, TX 77381, Academy of Athens, Division of Natural Sciences, 28 Panepistimiou Avenue, Athens 10679, Greece.

2.$1,000 Does Inflation Provide Natural Initial Conditions for the Universe? by Sean M. Carroll and Jennifer Chen, Enrico Fermi Institute, Department of Physics, and Kavli Institute for Cosmological Physics, University of Chicago, 5640 S. Ellis Avenue, Chicago, IL 60637.

3.$750 Gravity from Local Lorentz Violation, by V. Alan Kostelecky* and Robertus Potting+, *Physics Department, Indiana University, Bloomington, IN 47405; +CENTRA, Physics Department, FCT, Universidade do Algarve, 8000 Faro, Portugal.

4.$500 Gravity-Wave Detectors as Probes of Extra Dimensions, by Chris Clarkson and Roy Maartens, Institute of Cosmology and Gravitation, University of Portsmouth, Portsmouth PO1 2EG, UK.

5.$250 Classical and Quantum General Relativity: A New Paradigm, by Rodolfo Gambini* and Jorge Pullin+, *Instituto de Fisica, Facultad de Ciencias, Igua 4225, esq. Mataojo, Montevideo, Uruguay; +Department of Physics and Astronomy, Louisiana State University, Baton Rouge, LA 70803-4001.

Selected for Honorable Mention this year were (listed in alphabetical order)

D.V. Ahluwalia-Khalilova; Giovanni Amelino-Camelia; Vijay Balasubramanian, Vishnu Jejjala, and Joan Simon; Mihai Bondarescu; Xavier Calmet, Michael Graesser, and Stephen D.H. Hsu; Saulo Carneiro; F.I. Cooperstock; F. de Felice; Cedric Deffayet; Alessandro Fabbri and Jose Navarro-Salas; G.W. Gibbons, H. Lu, Don N. Page, and C.N. Pope; Yuan K. Ha; Veronika E. Hubeny, Mukund Rangamani, and Simon F. Ross; Viqar Husain and Oliver Winkler; Mark G. Jackson; David W. Kraft; Jnanadeva Maharana; M.D. Maia; Hrvoje Nikolic; T. Padmanabhan; Fabrizio Pinto; Sanjeev S. Seahra; M. P. Silverman; C. Sivaram; Dejan Stojkovic, Glenn D. Starkman, and Fred C. Adams; John Swain; Daniel R. Terno; Paul S. Wesson; G.Z. Xie and Hong-Tao Liu; Winfried Zimdahl.

Ah well, it’s not whether you win or lose, and all that. In the immortal words of Geddy Lee, “Ten bucks is ten bucks, eh?” Meanwhile, Mark fills us in on why you need a smooth patch of the early universe in order to start inflation.

I don’t have the strength/time/interest to slog through the entries at Arianna Huffington’s celebrity blog, but others do. Tigerhawk highlights this piece by Larry David:

Why, even this morning my moronic assistant handed me a cup of coffee with way too much milk in it. I was incensed.

“You stupid ignoramus,” I screamed, doing all I could to restrain myself from tossing the luke-warm liquid in her face. “There’s too much freaking (I didn’t say freaking) milk in here! What the freak is wrong with you?!”

“I’m sorry, sir,” she stammered. Like sorry’s going to fix everything. I’m not interested in sorry. Sorry doesn’t cut it with me.

“Look, you idiot,” I continued, “I wouldn’t mind so much if you gave me too little milk. Little can be fixed. We can add to little.”

“Shall I get you another cup?”

“No, I’ll suck on my thumb. Yes, get me another cup, you douche bag! And chew on this — it’s going to cost you a dollar!”

It reminded me of a similar anecdote I had recently read — where was that, now? — ah yes, at Darth Vader’s blog:

I am aboard the StarDestroyer Avenger, en route to the outlands of Mordell at the galactic rim — but I started my morning on Coruscant. I was having my morning tea when the new girl came through to tell me the Emperor commanded my presence at the palace.

“Is your breakfast quite satisfactory, Lord Vader?” she asked.

It was not, but we shall let her next of kin worry about that.

Larry David wishes he was Darth Vader.

It looks like we may have seen the first moments of a black hole being born. This image (from Joshua Bloom’s web page) shows the optical counterpart of a new gamma-ray burst discovered by the Swift satellite. It seems likely that this event has resulted from the coalescence of two neutron stars. As the neutron stars spiral together, the smaller one is ripped apart by tidal forces, spreading into a disk of material. Some of the material accretes on the remaining neutron star, which reaches the point of no return and explodes, creating a black hole. Part of the matter outside the black hole is violently ejected, crashing into the surrounding interstellar medium, producing the flash of gamma-rays detected by Swift.

I won’t go into too many details about the story, since Steinn Sigurðsson knows this stuff much better than I do, and has explained what is happening in a series of great posts (one, two, three), from which I’ve stolen everything I’m writing here (and apologies in advance for what I mess up). Gamma-ray bursts are ultra-high energy events at cosmological distances (i.e., well outside our galaxy) that have fascinated astrophysicists for years now. The crucial point is that there are two types of bursts, long-duration (a few seconds) and short-duration (hundredths of seconds). The long-duration bursts are thought to arise from especially violent supernova explosions, and are typically found in galaxies undergoing copious star formation. The short-duration ones are likely to come from the coalescence of compact objects like neutron stars or black holes. This leads to a couple of expectations: close binary systems of compact objects can take a very long time to coalesce, so there’s no reason to find them near star-forming regions (all the stars having formed long ago). Also, the closeness of the binary often arises through close gravitational interactions with other stars, which can serve to give the binary a serious kick, so that it zooms right out of the host galaxy.

However, until now astronomers had never been able to pinpoint an optical counterpart to a short-period burst. (It’s hard to determine the direction from which gamma rays are coming. Swift uses a multi-stage technique, in which it first detects the gammas and then zooms in with X-ray and optical telescopes.) The image above shows the optical counterpart of this particular burst, GRB 050509b. It is short-duration, and appears to be lurking on the outskirts of a giant elliptical galaxy. Such galaxies are no longer forming stars, and the fact that the object is outside the galaxy proper (by perhaps 35000 parsecs) makes it fit nicely with the coalescing-neutron-star model. So those few glowing pixels are perhaps the baby photos of a new black hole. Amazing what stories astronomers can spin from such sparse data.

Update: In the comments, Matt points out that the purported optical counterpart doesn’t seem to be varying, which a real gamma-ray burst afterglow certainly would be. But as Steinn says, the X-ray counterpart is definitely there.

Jennie Chen and I have written a short essay for the Gravity Research Foundation Essay Competition. You can find it at gr-qc/0505037; it’s basically a distillation of some of the philosophical parts of our longer paper on the arrow of time. Nobody claims to have a really clear picture of the onset of inflation, but two possibilities are invoked most frequently: either “chaotic” initial conditions (a la Linde), or creation of the universe from nothing. We critique the former (following Penrose) on the basis that an appropriate proto-inflationary region is fantastically unlikely to occur randomly, much more unlikely even than the spontaneous appearance of our universe in its current state. And we critique the latter by noting that it violates time symmetry in a completely ad hoc fashion — why impose certain boundary conditions at early times but not at late times? Our solution to the conundrum is to imagine a nearly-empty de Sitter state that forms the “backbone” of the universe, off of which new inflationary regions are occasionally generated via thermal fluctuations.

The Gravity Research Foundation is a funny institution, originally founded by Roger Babson (who also founded Babson College) in order to promote research into neutralizing the effects of gravity. That’s hard to do (impossible, if what we think we know about gravity is anything close to correct), and the Foundation was originally home to quite a few cranky ideas. But more recently it has become more respectable, and nowadays seems to not do much other than sponsor these essay competitions, which feature a lot of very interesting papers by respectable people. My one previous time entering (as a grad student), I got an honorable mention, which is not very hard. This time I’m hoping for some big bucks.

And if you’re not overly fond of my philosophizing, try out the Beatles’. “McCartney elaborates Frege’s sense/reference distinction.” (Via Brian Leiter.)

Greetings from Geneva, world center of banking, watches, and high-energy physics. (Three fields of endeavor which, not coincidentally, each place a premium on exquisite precision.) I’m at CERN for the week, giving a set of academic lectures on “Cosmology for Particle Physicists.” (Wow, I just gave the first lecture a couple of hours ago, and the video is already up! Welcome to Switzerland.) Here are the slides as html and a 1.2M pdf file. Nothing you haven’t seen before, in the likely event that you’ve been reading all of my talks as I put them on the web.

Four more lectures to come, slightly more detailed and technical than the introductory gee-whiz first lecture: 1. Dark matter and dark energy; 2. Thermodynamics in the early universe; 3. Perturbations and large-scale structure; 4. Inflation and beyond. Also unlike the first lecture, these will be on the blackboard instead of from some pretty computer presentation. Because I’m hard core, baby.

If I weren’t tired from jet lag and facing four more lectures to write, I’d regale you with witty anecdotes from the plane trip here. Like, how I couldn’t get past level 18 of the Caveman video game that Swissair provides to keep you from getting any sleep at all during the flight. Those damn red mammoths kept catching me.

We’re in the midst of the University of Chicago’s famed Scav Hunt, in which teams of energetic, creative, and sleep-deprived undergraduates scour the universe for all sorts of unusual objects. (The link is correct, trust me.) This year the hunt is being blogged by Connor Cyone, and the list of items can be found here (pdf). And yes, as Will Baude mentions, I do make an appearance in item 48: “Retrieve information from a black hole. Must be Sean Carroll certified. [4 points]” Consequently, I have been asked by three different teams to certify that they have indeed extracted information from a black hole, just like Hawking says we can. Accommodating soul that I am, I readily signed my name to various pieces of paper that can now be used to discredit me in the future. All for a good cause.

No more teams are likely to find me, as I am off to Geneva to spend the week at CERN giving lectures on cosmology. Do they have the Internets in Europe? Perhaps I will check in.

So, I think we set a record for visitors to Preposterous yesterday. Mark also noticed that even his blog got a lot more visitors than usual. From this we derive an obvious lesson: if you want to generate traffic, you should write about me. (Not “yourself,” you understand — you should write about me, Sean.)

Seriously, I am overwhelmed by the outpouring of supportive comments. They mean a lot to me. But I do want to clarify one point. When I mentioned that blogging will be a low priority, nobody should read that as “while I drink heavily and wallow in self-pity.” (Self-pity will not be involved.) Rather, it’s “since I don’t have much time while I scramble to get some other things done.” Perhaps I am simply in an early, denial-based phase, but at the moment I am in no danger at all of questioning myself. I am questioning the judgment of some people, but not of myself. Hopefully I will soon find time to write the posts I have in mind on wormholes, amateurs, string theory, and co-evolutionary learning. (Those are separate posts, not one big one — although that would be fun.)

In the meantime, I understand there are other blogs out there. All the ones on the blogroll are written by witty and charismatic thinkers, I encourage you to visit. (To pick two at not-quite-random, Shakespeare’s Sister and Ezra Klein are a couple I should be linking to much more often.) And don’t forget the “next blog” button in the top right corner, which is a source of constant delight. Today I discovered Sharon Spotbottom, which has some interesting and provocative cartoons. But it will be hard to beat my all-time favorite, the Bean Bag Blog.

The bad news is that I’ve been denied tenure at Chicago. It came as a complete surprise, I hadn’t anticipated any problems at all. But apparently there are a few of our faculty who don’t think much of my research. A stylistic clash, I imagine. And a handful of dissenters is all it takes to derail a tenure case. I don’t think there are many people in the outside world who believe that the University of Chicago is better off without me than with me, but there seems to be an anomalously high concentration of them among my own colleagues.

So now I am on the job market again. Which is sad, both because of the intrinsically demoralizing nature of the job market, and because I cannot tell you how much I love this city and the friends I have made here. It truly feels like home to me. But I’m hopeful of getting a position at some other great place and flourishing there — doing well is the best revenge.

In the meantime, though, blogging will likely be a low priority. I’m not going to stop, but my former ambition to put something up every day (no matter how lame) is going to be set aside as I concentrate on other things.

Further updates as events warrant.

You only ever need one time traveler convention. Because, of course, future time travelers can find out about it, and then come back in time to attend. The trick is publicity. So I am hereby doing my part, secure in the knowledge that Preposterous Universe will last for millennia, at least in archive form.

(Okay, I have to admit that this is somewhat bogus. A real time machine, i.e. a closed timelike path through spacetime, would only ever be able to take you back to the moment when it was originally created, not into the pre-existing past. So the convention will only work if someone has already built a time machine. But who knows?)