Blogs / Cosmic Variance

The results are in for the Foundational Questions Institute essay competition on “The Nature of Time,” which we discussed here. And the winners are:

First Juried Prize:

Julian Barbour on “The Nature of Time”

The jury panel admired this essay for its crystal-clear and engaging presentation of a problem in classical dynamics, namely to find a measure for duration or the size of a time interval. The paper argues lucidly, and in a historically well-informed manner, that an appropriate choice for such a measure is not to be found in Newton’s pre-existing absolute notion of time, but rather emerges, in the form of ephemeris time, from the observable motions and the assumption of energy conservation. The paper also suggests how this emergence of duration might be relevant to problems in quantum gravity.

Second Juried Prizes:

(1) Claus Kiefer on “Does Time Exist in Quantum Gravity?”

A fundamental problem in quantum gravity is that the “Wheeler-DeWitt Equation,” probably our most reliable equation of quantum gravity, does not refer to or even suggest anything like time or evolution. In this context time must emerge in the form of relations between a given system and some other system that may be considered a clock. Kiefer beautifully reviews this problem, and argues how, via quantum “decoherence,” time as described by the usual Schroedinger equation in quantum mechanics can emerge from this timeless substratum, via entanglement between physical systems within space, and the spatial metric that controls motion.

(2) Sean Carroll on “What if Time Really Exists?”

Drawing on recent developments in string theory, Carroll impressed the panel with an exciting account of how a gravitating spacetime might in fact be just a holographic approximation to a more fundamental non-gravitating theory for which “time really exists.” Contemplating the difficulties raised by strange recurrences in an everlasting universe, he argues for a strong condition on the set of allowed quantum states that would disallow such repetitions. Carroll closes by attempting to reconcile this picture with recent observations that indicate that the expansion of the universe is accelerating, with surprising results.

Tied for second is not at all bad, considering the number of interesting entries. There are more prizes, actually, as there are “community” awards as well as “juried” prizes, so check those out as well. It’s pretty amusing that the top three essays all attack, in one way or another, whether or not the subject of the competition actually exists. (I was in favor, the others were more skeptical.)

Besides the essays themselves, I very much appreciate the huge amount of work it must have been for the various judges to read through all of them and make hard decisions. Thanks to the FQXi for sponsoring the contest, and thanks to all the judges for doing a great job!

Many Cosmic Variance readers will recognize friend-of-the-blog Allyson Beatrice — frequent commenter, occasional solo blogger, and co-blogger at Cocktail Party Physics. For a while now, Allyson’s day job has been as an administrator and conference organizer for groups of scientists and engineers — a task of uncertain rewards which, for whatever murky reasons, she truly seems to love.

I’m a lab secretary. If I’m your lab’s secretary, I have access to your credit cards, your CV, your passport, and your society memberships. I could write a crackpot paper about string theory and its effects on pineapple custard and publish it under your name on Optics Express.

But I wouldn’t do that. My job is to get you to the plane on time so that you can present your brilliant paper on quantum physics and gravity in the solar system to a bunch of people whose lives revolve around fun new uses for cesium fountains. I have no idea what any of it means, but if some government bureaucrat gets in between you and your travels, I will cut a bitch to make sure you get to your conference.

Unfortunately, through a series of circumstances too forehead-slappingly stupid to be convincingly related here, Allyson is soon going to be out of her current job. (She gave her notice at her lab, under the impression that an even better gig had been lined up, before the rug was pulled out from under her.)

So — anyone in the LA area in the market for an extraordinarily talented and dedicated lab secretary? Whoever ultimately hires Allyson will be extremely lucky, but in this economy jobs don’t come easily. Things are tough all over, but it’s heartbreaking to see someone so good go jobless through no fault of their own. Email me and I’ll pass along any leads. And thanks.

Most physics fans out there have probably heard of Kip Thorne, author of Black Holes and Time Warps and some other books. If you polled physicists to find out who they thought had been the most influential American scientist doing research in general relativity over the past several decades, Thorne would win hands-down. (Here’s a recent interview in Discover.)

And if you dropped the delimiter “American” from the question above, the winner would undoubtedly be Stephen Hawking. So we’re very happy to have a guest post from Kip, announcing an upcoming talk by Hawking.

Left to right: John Preskill, Kip Thorne, and Stephen Hawking.

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Stephen Hawking is coming to town – to Pasadena, that is.

Caltech, in Pasadena, California, is Hawking’s home away from home. Since 1991 he has spent roughly a month a year here as our Sherman Fairchild Distinguished Scholar. This year he flies in from his English home at the end of February, then heads off to Texas in early April.

He arrives with an entourage of five care givers to tend to his physical needs, one or two family members, several graduate students, and a “graduate assistant” who handles logistics and serves as general fixit-person for his computer system and mechanized wheel chair. His current chair is new and sophisticated. At the flick of a switch, its hydraulics can lift him up to a standing person’s eye level or slide him down near ground level for high-speed chases — he has been known to take pleasure from running over the toes of university presidents.

Hawking’s Pasadena sojourns are rather like Einstein’s in the 1930s. Caltech is an intellectual magnet – a crossroad for ideas about the cosmos and the fundamental laws of nature, which are Hawking’s passion. He contributes mightily to the ferment, and partakes. Our California night life (LA, not Caltech!) is also pretty good; and Hawking, like Einstein, is a party animal, only more so. During his annual month here, my own social life intensifies five-fold just from being his closest California friend. He loves opera, theater, jazz clubs, barbecues that he hosts in the patio of his Pasadena home, and dinners with fine wine – especially an Indian Feast prepared for him by Caltech undergraduates. Yes, we geeks can cook up a storm – well, not me, but the younger generation.

Conversation with Stephen is slow, about 3 words a minute, produced by Stephen moving a muscle in his face (imaged by a lens and photodetector) to control a cursor on his computer screen. It’s slow, but rewarding. You never know, until his sentence is complete, whether it will be a pearl of wisdom or an off-the-wall joke. Faster speeds are on the horizon: computer control via brane waves, without drilling a hole in his head (he’s opposed to that). But he resists changing technology, even without drilling, until forced to. “I can’t believe it’s as good as what I have.” (It actually is; my wife has a friend with ALS who proves it so.)

Most of Hawking’s Pasadena time is spent thinking, conversing, and working on projects. Jim Hartle drives down from Santa Barbara to continue their decades-long research collaboration on the birth of the Universe. Leonard Mlodinow, a Pasadena-based free-lance writer, toils with him on a book: in the past, A Briefer History of Time; now, their forthcoming The Grand Design. And there are drives to Hollywood to film for Star Trek or the Simpsons or the forthcoming Stephen Hawking’s Beyond the Horizon.

On each Pasadena visit, Hawking gives a lecture for the general public – always before in Caltech’s limited-seating Beckman Auditorium, but this year in the newly renovated Pasadena Convention Center, at 8PM, Monday March 9. “Why We [the human race] Should Go into Space” is his title. It’s an opportunity to see him in action, be immersed in his mind’s world, and – if last year’s lecture is any indication – participate in a happening. Tickets are available from the Caltech ticket office, (626) 395-4652, at $10 each.

The last time I saw Hawking speak to such a large audience, thousands, was in a converted railway station in Santiago Chile, soon after General Pinochet’s regime gave way to civilian rule. It was quite a show. Hawking made a grand entrance to rock music and charmed the crowd. The President of Chile and other civilian officials sat on one side of the giant stage, the military brass on the other, with enormous tension between them; they were hardly speaking to each other in those days. Only Hawking could bring them into the same room. His aura works magic. The next day the military flew us to Antarctica: a C130 cargo plane filled with TV cameras, journalists and physicists. It was August, the Antarctic winter, the first flight to Antarctica in more than a month due to winter storms. It was a Hawking Adventure, one among many. He lives life to the fullest. He will fly on a rocket into space soon.

Back when I was fresh out of grad school, a mere pup still pinching myself that I was constructively participating in this marvelous endeavor called “science,” I noticed in a book store an issue of Time magazine proclaiming “America’s 40 Leaders Under 40.” Since, back in those days, I was technically eligible for honors and awards bestowed upon people under the age of 40 in a way that I no longer am, I turned to the article in anticipation. Perhaps they had written something about me without actually letting me know, right?

Somewhat to my surprise — there I was! Or someone with my name, in any event. Further sleuthing revealed that this guy was Sean B. Carroll, an evolutionary biologist in Wisconsin. Clearly there had been some sort of mixup on the part of Time magazine, but I would forgive them and him this once.

The problem is, the guy refuses to go away. He becomes some sort of evo-devo guru, gets elected to the National Academy of Sciences, writes books — and they’re good books! I’ve read some of them. I hate this guy.

But at least, through it all, I had the blog. A little realm of intellectual endeavor (ahem) that I could enjoy free of interference from other Sean Carrolls. True, the very first link to my own blog was from PZ, who expressed profound disappointment that I was not the other SC. But through it all, as I deflected occasional requests to referee papers about fruit flies or speak at fancy conferences on evolution, and accepted that I was not the first answer to questions like “Who is that Sean Carroll who does science?” or “Who is that Sean Carroll who writes books?”, I was at least the appropriate response if someone were to ask “Who is that Sean Carroll who blogs?” And I had the superior Google page rank to prove it.

So now, here in the Darwin Year, what does (former, I’m thinking) friend-of-the-blog Tom Levenson go and do? He recruits the other Sean Carroll for a blogging project! So Simple a Beginning seems to be the name, although the project itself doesn’t seem to “exist” quite yet. Blogging about The Origin of Species, blah blah blah.

I guess I need to find some other area of human accomplishment in which I am likely to be the leading Sean Carroll of the world for some time to come. Playing poker? Making ice cream? My skill set is rather circumscribed, it would seem. Suggestions welcome.

You know what the world really needs? A good book about time. Google tells me there are only about one and a half million such books right now, but I think you’ll agree that one more really good one is called for.

So I’m writing one. From Eternity to Here: The Quest for the Ultimate Theory of Time is a popular-level book on time, entropy, and their connections to cosmology, to be published by Dutton. Hopefully before the end of this year! I’ve been plugging away at it, and have shifted almost into full-time book-writing mode now. (Note to collaborators: I promise not to abandon you entirely.)

I have my own idiosyncratic ideas about how to account for the arrow of time in cosmology, but those are going to be confined to passing mentions in the last chapter. Mostly I’ll be discussing basic ideas that most experts agree are true, or true ideas that everyone should agree on even if perhaps they don’t quite yet, or the implications of those ideas for knotty questions in cosmology. Hopefully we can at least shift the conventional wisdom a little bit.

Naturally there is a web page with some details. Here is the tentative table of contents, although I’ve been cutting and pasting pretty vigorously, so who knows how it will end up looking once all is said and done. One thing is for sure, some of these chapter titles need sprucing up.

0. Prologue

Part One: Time, Experience, and the Universe

1. The Heavy Hand of Entropy
2. The Beginning and End of Time
3. The Past is Present Memory

Part Two: Einstein’s Universe

4. Time is Personal
5. Time is Flexible
6. Looping Through Time

Part Three: Distinguishing the Past from the Future

7. Running Backwards
8. Entropy and Disorder
9. Information and Life
10. Recurrent Nightmares
11. Quantum Time

Part Four: Natural and Unnatural Spacetimes

12. Black Holes
13. The Life of the Universe
14. The Past Through Tomorrow
15. Epilogue: From the Universe to the Kitchen
    Appendix:  Math

If anyone out there is friends with Oprah, maybe drop her a line suggesting that this would make a good book-club choice. I hear that’s helpful when it comes to sales.

Update: And now you can buy it.

Hey Raccoons!

You suck.

In 2007, my spring semester finished up with what was a truly remarkable weekend. Almost two years earlier, it had been brought to my attention that Syracuse had a particularly distinguished alumnus – Martin A. Pomerantz – in an area tightly connected to my own. Let me tell you a little about him.

Martin was the father of Antarctic astronomy. He graduated from Syracuse with an A.B. in physics in 1937 – the same year as the Hindenburg disaster, and went on to U. Penn and Temple and finally to the University of Delaware’s Bartol Research Institute, where he spent most of his research career – serving as it’s president for many years. Martin became a leader in the fields of submillimeter astronomy, cosmic and gamma rays, and measurements of the Cosmic Microwave Background radiation (CMB). In particular, he pioneered solar observations using helioseismology, becoming the first scientist to set up a telescope and observe the sun for 120 continuous hours from a single point on Earth. This kind of research is now the bread and butter of observational cosmology, and indeed, if one reads modern accounts of cosmology from the South Pole, Martin features prominently, and can be seen in photographs of the first team trying to measure the CMB from there. Our entire field has depended crucially on observations made in this pristine environment.

Because of these achievements, and his connection to Syracuse and one of our current research areas, my colleague Peter Saulson and I nominated Martin for an honorary doctorate. This nomination was ultimately successful, and we were informed that Martin was to be honored during our 2007 graduation.

So in mid-May, Martin, his son Marty, daughter Jane-Anne, son-in-law Steve and grandson Jonah arrived in Syracuse for our graduation weekend. On Friday May 11, we held The Martin A. Pomerantz Symposium, at which Peter and I gave talks, followed by a keynote presentation by our alumna – Gabriela González – and a summary talk by Martin himself. It was immense fun. Gabby’s talk in the afternoon was great – she is a Professor at Louisiana State University and an expert on the detection of gravitational waves, who had recently been awarded the American Physical Society’s 2007 Edward A. Bouchet Award. In addition to her research achievements, this award was also “for communicating the excitement of this field to the scientific community and the public”, and these abilities came through clearly in her talk.

Martin and his family clearly enjoyed the afternoon, but halfway through Martin started to feel ill, and we suggested canceling the rest of the program. But Martin declined, had some water, took a brief break, and insisted we continue, even though he looked a little weak and tired. The closing event was planned to be a slide show (yes, actual 35mm slides) presented by Martin, and discussing the early days of Antarctic astronomy, through his 27th and final visit to the pole at age 79 (during which the NSF recognized him by naming an observatory at the U.S. Amundsen-Scott South Pole Station after him). We were certain that Martin wouldn’t feel well enough to deliver this talk, but when the time came, he stepped up, faced the room, straightened his back and gave a remarkably energetic, animated and compelling presentation. He was just a different man when discussing his life’s passion.

The next evening we had a lovely dinner, with all the other graduates, and the following morning I presented Martin to the Chancellor to receive his honorary degree. It was obviously a proud moment for him, and it most certainly was for all of us, particularly for me, presenting someone who pioneered the kind of observations that are such an important part of my field. We sat on the stage, in front of the assembled crown of graduates and their families, in wonderful weather, and listened to Frank McCourt’s witty and thoughtful Commencement speech. And after lunch we all said our goodbyes and the Pomerantz clan headed off to the airport.

The Pomerantz family has been very good to Syracuse, endowing the Martin A. Pomerantz Professorship in Physics (the inaugural holder of which is Peter Saulson) and the Molly B. Pomerantz Graduate Fellowship, and the physics department is extremely grateful to them, as well as proud to have Martin as an alumnus. Martin couldn’t make it to the formal announcement of these gifts, but Marty was there, and we telecast it out to Marty and the rest of the family.

Soon after Martin’s visit to Syracuse he was diagnosed with cancer, which may explain why he felt bad during our symposium. The prognosis was quite bad, but he fought on remarkably well. Over the last 18 months or so we kept in quite close contact, and last November I was giving a talk at Berkeley, and was able to get together for dinner with Martin and his family, and finally to meet his wife, Molly. Even though he was in treatment, and over 90 years old, he looked great, and was full of energy. We talked about cosmology, and he wanted to know about the status of the field, and was telling me about some research he’d kept up with by reading articles online. It was a wonderful evening.

In the last month or so, through Marty, Martin’s devoted son, I’ve kept up with Martin’s condition, and knew that he’d been getting steadily weaker. I sent him the occasional article, and Marty told me he liked to read them.

On October 26th Martin Pomerantz passed away. He was a terrific physicist, a true pioneer, a gentle and generous person and a caring father. I am proud to have gotten to know him, deeply sad that he is gone, and grateful to his family for the time they and he spent with me. He will be missed.

Frankly speaking, I am not big on change. Oh yeah, the Obama business was pretty good, and I recognize that change is necessary for progress, blah blah blah, but man, it doesn’t come easy for me.

I was made excruciatingly aware of this by my stubborn refusal to log into CV’s back end at our new home. Why? Because it was going to be <cringe>different</cringe>.

I actually can’t make any sense of this behavior on my part, because science is all about change. I have no problem changing topics and points of view in a scientific context. Want to know what I’ll be working on in 5 years? It’ll probably be found in the set of things on which I am currently not working, nor have ever worked on before.

But technologically-driven changes in my day-to-day behavior? Scaaaaaary. One of my students mistakenly assumed that I was a bleeding edge of technology sort of person, based on my spiffy new MacBook Air. However, the only reason I have a new laptop is because after six and a half years, my old one was sufficiently dented that I couldn’t close it anymore, and it made ominous noises when writing to disk. Oh, I could have afforded a new laptop at many points in the intervening years, but then I’d have to install software or learn to use Leopard, and that, my friends, is not change I can believe in.

So, this post is my attempt to get past the queasiness and start defining this as the new normal.

And hey! Did you see the new images of extrasolar planets?!

Ok. That didn’t hurt a bit.

The arena at Politico.com has an interesting Q&A today. The question is “What, for you, was the most memorable moment of this long race for the presidency.” The responses run from the obvious (Obama’s now famous race speech) to the very personal (`my 6-yr old daughter didn’t realize that a woman had never been president of the US’). Anyway, I invite you all to go have a look, provided you enjoy year-end lists.

And, I’d thought it would be great to hear from the ultra-intelligent, ultra-interesting, avid CV readers what their response is to this question. So, please, write a comment and let us know, “What, for you, was the most memorable moment of this long race for the presidency.”

I’ll start! For me, the most memorable moment happened last Saturday. I had just returned from China and called my parents to let them know I was home. The conversation turned to politics, inevitable this time of year. Usually we step on eggshells whenever this subject arises (my parents are die-hard Republicans, but I love them anyway), but this time we were all speechless. In awe of my Uncle Chuck.

Uncle Chuck is my favorite uncle – we are the scientists in the family. He came home after serving in the Navy in the South Pacific during WWII and went to school on the GI bill. Ended up with a master’s in mathematics. Worked at Oak Ridge National Lab on the very first computer systems. Went on to NASA and was one of the folks in charge of the computer program rewrites to get the Apollo 13 astronauts safely back home. He has done tremendous things and is very smart. But, he’s lived most of his life in the deep South and has somehow developed a deep racial prejudice that most of the family can’t understand. We have cringed for years whenever he has espoused on the virtues of the Bell Curve in regards to race. I could go on, but think I’ll hold back and just say he is the most racially bigoted person I know. I can’t fathom some of the things I have heard him say.

On Saturday, I learned that Uncle Chuck cast his early ballot for Senator Barack Obama for President of the USA. Nothing could have surprised me more! No matter what happens with the election tomorrow, Obama has already stirred deep, positive change in our society.

Ten or fifteen years from now, virtual worlds will be as prevalent as web pages are today. I remember fifteen years ago when I had just set up my first web page and was trying to explain to my friends that this was going to be really big. Suffice it to say, I wasn’t very convincing. “The other day I found a web page that you can use to order a pizza to be delivered!” “You know, we already have a technology to do that — it’s called a phone.”

Likewise, I don’t have an especially clear picture of how virtual worlds will be put to use in the years to come. Right now, by far the leading presence in the game is Second Life, which remains clearly marked by the signs of geekdom which tend to characterize early incarnations of technological advances — for example, you have to choose a pseudonym for your avatar, the surname of which must come from a list of more-or-less goofy selections. And, admittedly, the most popular activities seem to be roleplaying and cybersex. Not that there’s anything wrong with that.

But the scientific community is catching on. Rob Knop, erstwhile astronomer and science blogger, now works for Linden Labs, creators of Second Life. Organizations like the Exploratorium have set up bases in SL, and one ambitious fan of the Large Hadron Collider built a mock-up of the ATLAS detector. At the research level, astronomers have set up the Meta Institute for Computational Astrophysics, which uses SL and other virtual worlds for a number of different activities — collaboration meetings, data visualization, outreach, etc. Piet Hut of the Institute for Advanced Study, who founded the group, has posted a few papers on the arxiv about how he envisions the possibilities, e.g.:

Virtual Laboratories and Virtual Worlds
Piet Hut (IAS, Princeton)

All of which is preamble to mentioning that Rob has invited me to give a popular talk in Second Life, which (I think) will be happening next Saturday, November 8, at 10 a.m. Pacific time. So if you regret not being able to come to my arrow of time talk in so-called “real life,” here is your chance to hear it. It’ll be taking place at the Galaxy Dome at Spaceport Bravo — that’s a Second Life URL, or SLURL; if you have already signed up, just click that link to appear at that location in-world (as they say). It looks something like this:

Chances are that you don’t have your own Second Life identity, but here’s your excuse to join up and spend a couple of hours this weekend building your avatar and buying clothes. There’s no need to spend any money at all if you don’t want to, but if you do, there is a real economy with its own currency and a variable exchange rate with US dollars. (Just like real life, fashion choices for women vastly outnumber those for men. Unlike real life, you get to buy your skin and hair, or even your shape — or just modify the default stuff you are created with.) Here’s a useful startup guide, if you don’t mind receiving instructions from a mermaid.

Look forward to seeing you Saturday. Or rather, Seamus Tomorrow does.