Blogs / Cosmic Variance

Well, here goes with my first post after the big Discover move - welcome to any new Cosmic Variance readers!

On Sunday I returned from a wonderful week in Southern California, during which I worked hard, attended many talks, spent much time discussing science, and purely coincidentally got to enjoy exquisite weather and tremendous dining. On the previous Monday I had arrived in Claremont, home to the appropriately named Claremont Colleges, where on Tuesday I spent the day in the physics department at Pomona College, and ultimately delivered the departmental colloquium. I was speaking on “Is Cosmic Acceleration Telling Us Something New About Gravity?”, to a healthy-sized audience, given that the timing coincided with the polls closing in a number of states critical to the outcome of the presidential election (I was assured that the open laptops of some audience members were being used purely for taking notes.)

I finished on time and then marveled as the audience, determined to demonstrate their devotion to science over politics, asked question after question about how one constructs infrared modifications of gravity, how to evade solar system tests and the pitfalls of horrible instabilities, and then how we might use future cosmology missions to probe our understanding of gravity on the very largest scales. This was, of course, wonderful fun. But in due course our minds turned back to the potentially historic nature of the day (other than my colloquium, of course) and I left campus with my graduate school housemate Dwight, and our friend Patti, who came out from LA, and went in search of a large television and much wine with which to celebrate. We were, it is fair to say, deliriously happy about the Obama victory, but saddened that Californians seemed destined to write discrimination right into their constitution via Proposition 8, which appeared sure to pass.

On Wednesday, I awoke smiling at the prospect of a possible return to rationality in the white house, and drove in the beautiful sunshine down to Newport Beach, in anticipation of a fascinating three days to come. A couple of years ago, I took part in the Kavli Frontiers of Science Symposium. I was subsequently asked to join the organizing committee, and this year, my final one attending this meeting, I am chairing that committee. As I’ve mentioned before, this conference, supported by The Kavli Foundation, and run by the National Academy of Sciences, is one of my favorite, most intellectually satisfying events of the year. Unlike other meetings I go to, this one features invited speakers and attendees across most scientific fields, all under 45 years of age, for almost three days of talks, questions sessions, poster sessions, and intense interactions (in a great setting - the National Academies Beckman Center on the UC Irvine campus - with great food).

My session this year was on Quantum Gravity, and I was lucky enough to have recruited three talented and distinguished speakers. Leading off the session was my former colleague, gravitational physicist and oft-times string theorist, the irrepressible Don Marolf from the University of California, Santa Barbara. Don is one of the most enthusiastic speakers you’ll ever hear, and was the ideal person to bring the often highly-technical and abstract reasons why we need a theory of quantum gravity to our audience of smart-as-a-whip-but-mostly-non-physicist scientists. Don’s warm-up act then segued into a talk on the best known approach to these problems – string theory - by renowned Stanford theorist Eva Silverstein. Eva took the tack of spending part of her time describing string theory, but mostly focusing on the hope that cosmology might provide us with a fertile testing ground for this way of thinking about quantum gravity. She talked about some string theory models of the early universe (inflation, and string theory cosmic strings for you experts), and how these may leave their fingerprints on the cosmic microwave background radiation, and particularly on its gravitational wave components.

The final speaker was Laurent Freidel, from the Perimeter Institute. Laurent works on other approaches to the quantum gravity problem, and faced perhaps the largest hurdle with this audience, since although almost everyone has heard of string theory, approaches such as loop quantum gravity are far less a part of the common lexicon. Nevertheless, Laurent jumped in with both feet and did a tremendous job of getting across the basic ideas and challenges, and where he felt these differed from string theory. I felt that the session went very well, and questions filled the allotted 45 minute period after the presentations, and we continued to answer questions about quantum gravity, cosmology, and wider physics topics, for most of the rest of the week.

Ours was the first session. Over the next two days there were seven other sessions:

• Cryptography and Computer Security
• Ever closer to Pandora’s box: Zoonotic Transmission of Viruses to Humans
• Extrasolar Planets
• Food and Fuel
• Multiple Systems in Understanding Addiction
• Suspended Animation, Immortality, Regeneration
• The Expanding Frontier of Nucleic Acids Chemistry and Biology

There was plenty to enjoy here, but I’ll single out the beginning of the immortality session as particularly fascinating, as the speaker, Alejandro Sanchez, of the University of Utah described his work on the regenerative properties of planaria (flatworms). These creatures can regenerate no matter what you do to them, and their regenerative properties can be genetically modified so that, for example, they grow a head wherever they are cut. Lest you think this work is part of a master plan to give us all multiple heads, the real goal is to understand how such amazing regeneration works, so that perhaps humans can ultimately replace their own malfunctioning body parts.

If you are a scientist and you are ever lucky enough to be invited to one of these meetings you should just say “yes!”. Sure, it won’t directly further your immediate research, and there probably won’t be anyone there who can directly further your career. But these are good things, making for a remarkably refreshing, open and fun meeting, at which all there is to accomplish is learning. Revolutionary, no?

Well, it’s back to a busy week for me. I flew back on Sunday, drove to Philadelphia for meetings on Monday, back yesterday, give the Cornell Astronomy colloquium tomorrow and need to go back to Philly early on Friday. Plus, today I am in bed with a horrible cold that I just hope isn’t something worse that those terrifying “Zoonotic Transmission of Viruses to Humans” people were carrying around.

It’s fun to finally have made the transition to Discover. If you’re new here, I hope you enjoy Cosmic Variance. Bye for now.