Andrew Jaffe: Leaves on the Line

As a scientist, I am used to my work being read by my peers, and I’ve made it into the occasional magazine or newspaper article, and even the odd TV and radio slot. But last week I travelled to Venice’s Architecture Biennale for the culmination of the first phase of the Architectural Association’s Beyond Entropy art/science project (which I’ve described before). I took a vaporetto to the island of San Giorgio, and next to one of Venice’s more spectacular Palladian churches, I saw the Beyond Entropy banner hanging over the entrance:
(I took these pictures, but there are many much more professional ones taken by the AA’s Valerie Bennett.)

Before arriving, I didn’t know what to expect from the project: small-scale, low-key, amateurish? In this setting, it was clearly big and serious. And inside this lovely building were these, the prototypes for our time machine:

Last year I traveled to South America to witness the launch of our several-hundred million-Euro Planck satellite, surely a big and serious project. But the sight of my own work — our texts, flywheels and gyroscopes — sitting on a plywood plinth, plausibly described as something at least related to the very different creative process of art, was nearly as disconcerting (despite the lack of highly explosive rocket fuel).

I’ll leave any assessment of the overall quality to others, although it became obvious that these pieces really are prototypes for what could become more finished works, but we have a long way to go. Nonetheless, let me explicitly thank my collaborators, Shin Egashira (whom I will also congratulate on his wedding which gave him an excellent reason to not show up in Venice) and Scrap Marshall, a student at the Architectural Association who joined us toward the end of the project and did an enormous amount of practical and creative work getting our pieces together. From speaking to members of  some of the other groups, we were lucky to all be based in London, and to eventually come to see our project in similar ways, albeit from different directions; some of the more widely-dispersed groups had to deal with significantly greater practical problems, and the interpersonal ones those ended up causing.

That first day was dedicated to the AA’s visiting school, and the next day was the centrepiece: a marathon symposium of more than thirty talks, dedicated to the themes of “entropy” and “energy”. Remarkably, none of our projects addressed the ecological, societal and political aspects of these topics, while many of the speakers attacked them directly, from Richard Burdett and Reinier de Graaf’s complementary discussions of the bleak picture for energy and climate if we keep to “business as usual” in our habits of consumption and production, to Italian Green Party politician Grazia Francescato’s hopeful discussion of “Green Jobs and Green Economy”. There were a few talks on science per se, from Angelo Merlina’s brief introduction to the LHC at CERN (of which a third talked about cosmology, and a third was pre-recorded), to one of my favourites, biophysicist Tania Saxl’s description of the amazing mechanism behind the motion of rotating bacterial flagella. There was also an inexplicable prerecorded description of “parallel worlds” in film from de Gruyter and Thys, a performance from the Arazzi Laptop ensemble, and contributions from Serpentine Gallery curator Hans-Ulrik Obrist (which was interesting but mostly about himself) and Charles Jencks. Jencks tackled the overlap between science, art and architecture head-on, each as a different metaphorical system for describing and interacting with the world. This culminates in his Scottish Garden of Cosmic Speculation, a hugely symbolic landscape replete with double helixes and grassy knolls in the form of black hole spacetime diagrams (I admit I’ve also found these supposed metaphors a bit too, well, literal for my taste — with insufficient information to be effective teaching tools, but too didactic to be truly beautiful.) I think the most important thing I learned was that, in their own way, the architects are just as nerdy as us scientists, but just better looking dressed.

Also, there was plenty of fine food and free-flowing sparkling wine (which meant that I probably missed about half of the presentations).

Finally, I would like to thank everyone from the AA who made the project happen (and will continue to do so, if further funding is forthcoming): Artemis Doupa, Sylvie Taher, Esther McLaughlin, Aram Mooradian and most especially the ever-enthusiastic project director, Stefano Rabolli Pansera. Thanks also to the AA visiting students, and all of the other participants, especially Ariel Schlesinger and Wilfredo Prieto for giving me a glimpse of the Architecture Biennale through artists’ eyes.

Every ten years or so, the US astronomy community, under the auspices of the National Academy of Sciences, produces a road map for the next decade’s research in astronomy. The 2010 version, chaired by Roger Blandford, was just released, and astronomer/bloggers have already weighed in: Steinn Sigurðsson and Julianne Dalcanton (in two separate posts on the ground- and space-based recommendations), along with the UK’s Andy Lawrence and Peter Coles have already dissected the report, but I’ll repeat the headlines: the Large-Scale Synoptic Telescope (LSST) is the top ground-based project, and WFIRST is the top-rated satellite — essentially the JDEM mission, rebranded as a broader infrared telescope with major science goals in both the study of dark energy and the hunt for extraterrestrial planets. The biggest surprise comes down the satellite list: the LISA interferometric gravitational-wave telescope is placed above the IXO x-ray satellite, which is only recommended for technology development (albeit at the not inconsiderable level of $180M). Alongside these large missions there is a recommendation for an expanded role for “explorer missions” in the tradition of WMAP, Swift and GALEX.

The big question on this side of the Atlantic is what impact these recommendations (and that is all that they are — NASA, NSF and DOE still make the real decisions) will have on ESA and the various national agencies. The EU astro community has a broadly similar initiative, Astronet, but the political and funding situation is sufficiently different that no one expects it to have as concentrated an impact on European astronomy as the decadal report has in the US. Moreover, both NASA and ESA have stated — I’m not sure how officially — that any future missions are likely to be shared on an 80/20 basis, rather than a more equal 50/50 model that has been discussed for both LISA and IXO.

If this is the case, then perhaps the US is ceding x-rays to the European astronomy community, but claiming the lead for space-based gravitational radiation and infrared astronomy, which raises the question of the place of the EUCLID dark energy mission in the ESA program. Indeed, the next ESA decisions for EUCLID, IXO and LISA are all expected in the coming months, and the level of NASA/ESA cooperation will likely be crucial to the outcome.

[Apologies to those of you who may have seen an inadvertantly-published unfinished version of this post]

I’ve just returned from a week at the Annual meeting of the Institute for Mathematical Statistics in Gothenburg, Sweden. It’s always instructive to go to meetings outside of one’s specialty, outside of the proverbial comfort zone. I’ve been in my own field long enough that I’m used to feeling like one of the popular kids, knowing and being known by most of my fellow cosmologists — it’s a good corrective to an overinflated sense of self-worth to be somewhere where nobody knows your name. Having said that, I was bit disappointed in the turnout for our session, “Statistics, Physics and Astrophysics”. Mathematical statistics is a highly specialized field, but with five or more parallel sessions going on at once, most attendees could find something interesting. However, even cross-cutting sessions of supposedly general interest — our talks were by physicists, not statisticians — didn’t have the opportunity to get a wide audience.

The meeting itself, outside of that session, was very much of mathematical statistics, more about lemmas and proofs than practical data analysis. Of course these theoretical underpinnings are crucial to the eventual practical work, although it’s always disheartening to see the mathematicians idealise a problem all out of recognition. For example, the mathematicians routinely assume that the errors on a measurement are independent and identically distributed (“iid” for short) but in practice this is rarely true in the data that we gather. (I should use this as an opportunity to mention my favourite statistics terms of art: homoscedastic and heteroscedastic, describing, respectively, identical and varying distributions.)

But there were more than a couple of interesting talks and sessions, mostly concentrating upon two of the most exciting — and newsworthy — intersections between statistical problems and the real world: finance and climate. How do we compare complicated, badly-sampled, real-world economic or climate data to complicated models which don’t pretend to capture the full range of phenomena? In what sense are the predictions inherently statistical and in what sense are they deterministic? “Probability”, said de Finetti, the famous Bayesian statistician “does not exist”, by which he meant that probabilities are statements about our knowledge of the world, not statements about the world. The world does, however, give sequences of values (stock prices, temperatures, etc.) which we can test our judgements against. This, in the financial realm, was the discussion of Hans Föllmer’s Medallion Prize Lecture, which veered into the more abstract realm of stochastic integration, Martingales and Itō calculus along the way.

Another pleasure was the session chaired by Robert Adler. Adler is the author of a book called The Geometry of Random Fields, a book which has had a significant effect upon cosmology from the 1980s through today. A “random field” is something that you could measure over some regime of space and time, but for which your theory doesn’t determine its actual value, but only its statistical properties, such as its average and the way the value at different points are related to one another. The best example in cosmology is the CMB itself — none of our theories predict the temperature at any particular place, but the theories that have survived our tests make predictions about the mean value and about the product of temperatures at any two points — this is called the correlation function, and a random field in which only the mean and correlation function can be specified is called a Gaussian random field, after the Gaussian distribution that is the mathematical version of this description. Indeed, Adler uses the CMB as one of the examples on his academic home page. But there are many more application besides: the session featured talks on brain imaging and on Google’s use random fields to analyze data about the way people look at their web pages

Gothenburg itself was nice in that Scandinavian way: nice, but not terribly exciting, full of healthy, attractive people who seem pleased with their lot in life. The week of our meeting overlapped with two other important events in the town. The other big meeting in town was the World Library and Information Congress — you can only imagine the party atmosphere in a town filled with both statisticians and librarians! But adding to that, Gothenburg was hosting its summer kulturkalas festival of culture — the streets were filled with musicians and other performers to distract us from the mathematics.

Last year, I ran for cats and dogs. This year, it’s a different half-marathon, Run to the Beat on September 26 (“London’s Music Half-Marathon”), with a less conveniently located course in East London, and I’ve shifted Kingdoms in my charitable support: I will run for “Trees for Cities”, “an independent charity working to improve the environment in urban areas by involving local people in community tree planting, training and landscaping projects”, in London, throughout the UK, and internationally. So if you like trees, and would like to keep me on the road for 13 miles, please give!

I spent part of this week in Paris (apparently at the same time as a large number of other London-based scientists who were here for other things) discussing whether the European CMB community should rally and respond to ESA’s latest call for proposals for a mission to be launched in the next open slot—which isn’t until around 2022.

As successful as Planck seems to be, and as fun as it is working with the data, I suspect that no one on the Planck team thinks that a 400-scientist, dispersed, international team coming from a dozen countries each with its own politics and funding priorities, is the most efficient way to run such a project. But we’re stuck with it—no single European country can afford the better part of a billion Euros it will cost. Particle physics has been in this mode for the better part of fifty years, and arguably since the Manhattan Project, but it’s a new way of doing things — involving new career structures, new ways of evaluating research, new ways of planning, and a new concentration upon management — that we astrophysicists have to develop to answer our particular kinds of scientific questions.

But a longer discussion of “big science” is for another time. The next CMB satellite will probably be big, but the coming ESA call is officially for an “M-class” (for “medium”) mission, with a meagre (sic) 600 million euro cap. What will the astrophysical and cosmological community get for all this cash? How will it improve upon Planck?

Well, Planck has been designed to mine the cosmic microwave background for all of the temperature information available, the brightness of the microwave sky in all directions, down to around a few arcminutes at which scale it becomes smooth. But light from the CMB also carries information about the polarisation of light, essentially two more numbers we can measure at every point. Planck will measure some of this polarisation data, but we know that there will be much more to learn. We expect that this as-yet unmeasured polarisation can answer questions about fundamental physics that affects the early universe and describes its content and evolution. What are the details of the early period of inflation that gave the observable Universe its large-scale properties and seeded the formation of structures in it—and did it happen at all? What are the properties of the ubiquitous and light neutrino particles whose presence would have had a small but crucial effect on the evolution of structure?

The importance of these questions is driving us toward a fairly ambitious proposal for the next CMB mission. It will have a resolution comparable to that of Planck, but with many hundreds of individual detectors, compared to Plank’s many dozens—giving us over an order of magnitude increase in sensitivity to polarisation on the sky. Actually, even getting to this point took a good day or two of discussion. Should we instead make a cheaper, more focused proposal that would concentrate only on the question oaf inflation and in particular upon the background of gravitational radiation — observable as so-called “B-modes” in polarisation — that some theories predict? The problem with this proposal is that it is possible, or even likely, that it will produce what is known as a “null result”—that is, it won’t see anything at all. Moreover, a current generation of ground- and balloon-based CMB experiments, including EBEX and Polarbear, which I am lucky enough to be part of, are in progress, and should have results within the next few years, possibly scooping any too-narrowly designed future satellite.

So we will be broadening our case beyond these B-modes, and therefore making our design more ambitious, in order to make these further fundamental measurements. And, like Planck, we will be opening a new window on the sky for astrophysicists of all stripes, giving measurements of magnetic fields, the shapes of dust grains, and likely many more things we haven’t yet though of.

One minor upshot of all this is that our original name, the rather dull “B-Pol”, is no longer appropriate. Any ideas?

(Warning, scattershot blogging echo-chamber post follows.)

Last week I went to the Science Blogging Talkfest sponsored by the Biochemical Society and led by Alice Bell from Imperial’s excellent Science Communication program.

Partially because the event was mostly attended by science bloggers themselves, there was a bit of a preaching-to-the-converted sense to the proceedings. (I tried to engage in some good-natured tweaking, pointing out that probably the greatest influence of [supposedly] science blogging has been in absurdly dragged-out climategate saga, but I couldn’t get a rise out of the audience.) But it was heartening to see just how mainstream science blogging has become.

“Only” five years ago (scare-quotes denoting an eternity of internet-time), the academic-blogosphere chattered on about an anonymous article in the Chronicle of Higher Education which contended that bloggers were essentially unsuitable to be hired as faculty members, and a couple of years after that several of my colleagues felt the need to seriously restrict their blogging while searching for permanent positions. I was heartened to see that the question of whether blogging could actually hurt someone’s career seems to be less worrying. Although Petra Boynton said that one of her previous departments were less than enthusiastic about it, most of the panelists have found that, with an increased in impact and communication in general, blogging has taken its position as an effective way to engage with the public.

One of the more novel (to me) things going on at this meeting was the Twitter backchannel: the organizers projected a running stream of tweets marked with the #talkfest tag. It was a decent mix of jokes and apposite comments, especially including erstwhile MP Dr Evan Harris’ provocative comments about whether scientists should be forced to do public engagement at all. It’s certainly good that blogging and communication don’t hurt your career — but should they be requirements for scientific advancement? Not all scientists’ talents lie in that direction, and we shouldn’t expect them to. There was also a twitter discussion of the gender makeup of the panel, which was dishearteningly 1/6 female despite an audience of at least 50% women.

When science blogging started out as its own sub-genre in the middle of the decade, no one was quite sure what it would be for. Would it be used within science as an online lab notebook, or as a substitute or adjunct to papers? That doesn’t seem to have panned out — even in the post-’net open world, the structure of science encourages secrecy, at least until the work can be packaged into what are still more or less old-fashioned papers in what are still more or less old-fashioned journals (albeit with the important twist of pre-publication posting on the arXiv in many fields). Within collaborations, however, wikis, rather than blogs, have become ubiquitous as an easy way to communicate amongst scientists who are already expert — the easy ability to add small chunks of information is exactly what is needed. (Within the Planck Satellite collaboration, we actually use a wiki as a sort of blog — we keep a reverse-chronological list of “posts” discussing our latest results.)

Instead, blogs seem to be used almost exclusively as a window into the life, methods and results of scientists, directed at a knowledgeable but lay public. Indeed, it was suggested at the talkfest that someone could make a very useful living textbook from the scattered blog posts on a given subject. I’m not so sure — one of the advantages of a proper textbook is a single voice and, more prosaically, a single notation starting from scratch— but it’s probably worth trying if someone’s got the wherewithal to do the bit-work involved.

It was especially nice to meet several of my fellow Imperial College bloggers, including biophysicist Stephen Curry (whose own post on the Talkfest also has a list of other reactions to it), whom I was somewhat embarrassed to discover actually works in the same building as I do. As always at these sorts of events, much of the amusement was during the inevitable pub visit afterwards and especially the pre-panel milling about — thanks to the organizers for the excellent combination of cupcakes and beer.

Two crucial figures from outside the mainstream of American culture have died.

Tuli Kupferberg (1923-2010) has been hanging around, writing about and stirring up trouble in New York’s Greenwich Village since the 1950s as a writer, poet, occasional political activist and rock ‘n’ roller. First in the late 60s and early 70s and occasionally thereafter, he was one of the Fugs (named after the faux-expletive from Mailer’s The Naked and the Dead) singing both the poems of William Blake as well as “Slum Goddess of the Lower East Side”. Since then, he kept writing, occasionally reformed the Fugs with his partner Ed Sanders, but had suffered a series of strokes in the last year from which he never fully recovered.

Harvey Pekar (1939-2010) was a bit better known. For the last few decades, he had been writing a series of autobiographical comics, “American Splendor”, illustrated by some of the best comics artists of the last few decades, from R. Crumb and Alan Moore to Gilbert Hernandez, Chester Brown and Joe Sacco.They chronicled his life in Cleveland, Ohio, from the tedium of his day job as a hospital clerk, a bout with cancer (in the excellent graphic novel “Our Cancer Year”), and his occasional run-ins with fame — in the 80s, he was occasional guest on David Letterman’s late-night talk show (until he famously decided to use his slot to lambaste GE, the owner of the NBC television network), and in this decade was memorably played by Paul Giamatti in a movie, also called “American Splendor”, based on the comics. Only a couple of weeks ago, I discovered The Pekar Project, devoted to getting and keeping his newest works online. He was always surly, too high-maintenance for his own good, dependably dissatisfied with whatever his life threw at him. And will nonetheless be missed.

The Planck Satellite was launched in May 2009, and started regular operations late last summer. This spring, we achieved an important milestone: the satellite has observed the whole sky.

To celebrate, the Planck team have released an image of the full sky. The telescope has detectors which can see the sky with 9 bands at wavelengths ranging from 0.3 millimeters up to nearly a centimeter, out of which we have made this false-color image. The center of the picture is toward the center of the Galaxy, with the rest of the sphere unwrapped into an ellipse so that we can put it onto a computer screen (so the left and right edges are really both the same points).

At the longest and shortest wavelengths, our view is dominated by matter in our own Milky Way galaxy — this is the purple-blue cloud, mostly so-called galactic “cirrus” gas and dust, largely  concentrated in a thin band running through the center which is the disk of our galaxy viewed from within.

In addition to this so-called diffuse emission, we can also see individual, bright blue-white objects. Some of these are within our galaxy, but many are themselves whole distant galaxies viewed from many thousands or millions of light years distance. Here’s a version of the picture with some objects highlighted:

Even though Planck is largely a cosmology mission, we expect these galactic and extragalactic data to be invaluable to astrophysicists of all stripes. Buried in these pictures we hope to find information on the structure and formation of galaxies, on the evolution of very faint magnetic fields, and on the evolution of the most massive objects in the Universe, clusters of galaxies.

But there is plenty of cosmology to be done: we see the Cosmic Microwave Background (CMB) in the red and yellow splotches at the top and bottom — out of the galactic plane. We on the Planck team will be spending much of the next two years separating the galactic and extragalactic “foreground” emission from the CMB, and characterizing its properties in as much detail as we can. Stay tuned.

I admit that I was somewhat taken aback by the level of interest in these pictures: we haven’t released any data to the community, or written any papers. Indeed, we’ve really said nothing at all about science. Yet we’ve made it onto the front page of the Independent and even the Financial Times, and yours truly was quoted on the BBC’s website. I hope this is just a precursor to the excitement we’ll generate when we can actually talk about science, first early next year when we release a catalog of sources on the sky for the community to observe with other telescopes, and then in a couple of years time when we will finally drop the real CMB cosmology results.

We get most of the official feedback on our teaching through a mechanism called SOLE — Student On-Line Evaluations — which asks a bunch of questions on the typical “Very Poor” … “Very Good” scale. I’ve written about my results before — they are useful, and there is even some space for ad-hoc comments, but the questionnaire format is a bit antiseptic.

On some occasions, however, students make an extra effort to let you know how they feel. Last year, I received an anonymous paper letter in the old-fashioned snail-mail post from a student in my cosmology course which said, among other statements, that I should “show appropriate humility and shame by not teaching any undergraduate courses at all this coming year.” Well, that year has come and gone, and I was not absolved of teaching responsibilities, so I soldiered on.

Today, I received another anonymous letter, from a most assuredly different student, who said that this year’s cosmology course “is without a doubt the most interesting undergraduate course I have taken at Imperial.” This would have left me ecstatic, except that this otherwise well-intentioned and obviously smart student managed to put the envelope in the mailbox with insufficient postage, which meant that I had to trudge across to the local mail facility and pay the missing 10p, along with a full £1 fee/fine! (If the author of the letter happens to read this, please consider a donation of £1.10 plus appropriate interest to the charity of your choice!).

It would be self-serving of me to make too much of this, beyond noting that, although I did make some significant changes in this year’s course, these letters more likely indicate the very different reactions that a given course can engender, rather than a vast improvement in my teaching.

My apologies to both students if they would have preferred I not quote them on-line, but such is the price of anonymity.

My colleagues and I spend what is probably an inordinate amount of time complaining about the occasional lapses of the basic skills of our students, their inability to take notes, their obsession with marks and what’s going to be on the exams. Because, like everyone else, we like to complain.

But pretty often I get the chance to see them at their best. In the Physics department at Imperial, we interview students who are on the boundaries between final “degree classifications”, the British system of awarding degrees as First Class, 2.1, 2.2, etc. Last week, I was on the panel for this year’s cohort. And it was a pleasure to sit in front of a few of our students and watch them, in real time, thinking like physicists. Of course this means making the occasional mistake, but it also means that delicious “aha!” moment when they figure something out and (this is the best part) they know that they have, whether it’s finding a sign error in their derivation of the motion of a pendulum, or a thought experiment explaining why Einstein’s relativity makes sense.

For the interviews, I was paired with one of our external examiners, UCL particle physicist and fellow-blogger Jon Butterworth. On the same day as our interview, the Guardian published Simon Jenkins’ latest in a series of risible anti-science screeds, and Jon decided to take him to task neither with reasoned argumentation nor with a counter-polemic, but with parody. As with many great ideas on the internet, this one got picked up and built upon, so that the Guardian, to its credit, eventually gave Jon his own space to reply. Jenkins likely thinks we’re producing too many scientists (Imperial only trains scientists, doctors, and engineers, after all!) but I hope that Jon was pleased with the ones he saw.

So my congratulations to this year’s graduating students, and the best of luck to them whatever they go on to do. Pace Jenkins, the world needs more well-trained scientists like them, not fewer.