Cocktail Party Physics

charity begins online

It's possible I have a streak of hypochondria. When I suffered the Amazing Five-Day Headache from Hell last December, there was, I admit, a brief period where I genuinely feared I might have a brain tumor... until I went online and every single authoritative site informed me -- with just a hint of exasperation -- that chronic headaches are statistically very unlikely to be linked to the onset of brain cancer. I guess they get that particular Google search a lot. And of course, in my case, those sites were right -- a visit to my doctor confirmed as much (and prescription strength headache meds put an end to the pain). But let's face it: the reason so many of us fear such things is because cancer is so prevalent in our society. Every one of us knows someone who has been diagnosed, suffered through surgery and/or chemotherapy, and in some cases, has died, from some form of the disease.

It's even more distressing when the patient is a child. Which is why we're taking time out at the cocktail party from posts about communicating science and the cosmos, and promoting Talk Like a Physicist Day, in order to promote a very different sort of event: the annual St. Baldrick's head-shaving fund raiser to benefit childhood cancer research, held this year on March 14 at Fado's Irish Pub in Chicago, among several other venues. I donated last year in support of regular CPP reader Matt Dick (he rewarded me by emailing a photo of his shiny new bald head). It's a fun, rowdy time, apparently, and all for a good cause. Makes me wish I lived closer to Chicago, despite those brutally cold winters.

Matt is participating again this year as a "Shavee," and I figured, in addition to making another small donation, I could help by spreading the word in hopes that some of my readers might be moved to also contribute to the cause. It's personal for Matt: his little cousin, Nathan, lost his fight with cancer (neuroblastoma, the most common of childhood cancers) last July, at the ripe old age of 6. It's too late for Nathan, but there are lots of other children out there who could be saved by a timely breakthrough in ongoing research. So check out the site, and if you feel moved, support Matt or one of the other Shavees.

There's some genuinely fascinating science going on related to cancer research. For instance, last year I wrote about the work of David Nolte's group at Purdue University developing a new holographic technique for imaging cancer cells to determine the effects of anti-cancer drugs on living tissue. Essentially, they can now measure the motion of organelles inside cancer cells to determine if they're living or dead, before and after the administration of anti-cancer drugs. (Organelles play a key role in fostering the out-of-control cancer cell division that so often proves fatal, so they are a primary target of drug therapies.)

New, more effective treatments are desperately needed. Matt told me about one prospective treatment that ultimately failed: injecting children with a neuroblastoma with T-cells drawn from mice exposed to a certain type of rodent virus, in hopes that the T-cells would kick into hyperdrive and aggressively attack the neuroblastoma. Alas, this didn't happen. In Matt's words, "While the mouse T-cells would go find the cancer cells, they just hung out at the scene not doing anything -- the idle youth of the immune system, I suppose." (Matt clearly has a knack for creative analogy.) Now the researchers are trying a new twist: treating the mouse T-cells with radioactive elements, then injecting them into the neuroblastoma, in hopes of achieving small-dose, targeted radiation to the cancer site.

Targeted drug delivery continues to be a very hot topic, particularly for cancer research, because chemotherapy and other standard treatments quite frankly have nasty side effects. More targeted drug delivery can help reduce those side effects, because more of the drug finds its way to the cancer cells, rather than to surrounding healthy cells in the patient's body. Neurosurgeons can usually successfully remove as much as 99.5% of a brain tumor when they operate, but we're talking about brain tissue here, so they can't be as aggressive about removal as they might be in other, less sensitive areas of the body. There's always a few scattered cancer cells left over, which is where the targeted delivery of powerful anti-cancer drugs comes in.

There's been some recent exciting progress in this area with the development of "gliodel wafers" -- essentially, disc-shaped implants infused with cancer-fighting drugs that are placed at the site where a tumor used to be just before the neurosurgeon closes everything up after removing a brain tumor. This means the drugs can dissolve and diffuse slowly into the surrounding brain tissue to kill any lingering cancer cells. The trick is getting past the blood-brain barrier, which is designed to keep stuff out. That's one possible reason why pharmaceutical agents don't appear to penetrate brain tissue uniformly -- something that still puzzles researchers.

Brain cancers are  especially challenging, as I discovered a couple of months ago when I chatted with George Lewis Jr., a researcher at Cornell BME who is working on finding ways to make targeted cancer drug deliver more effective. Some of the newer drugs are pretty darned powerful, and can easily stomp out those straggling cancer cells -- provided the drug can reach them. Cancer cells are tricky: they migrate to other areas of the brain rather quickly after surgery. Sure, it's only a few millimeters to a centimeter, but it's just enough to elude the drugs, with nasty results. "In two weeks you have tumors reappearing, and in two months, the patient is dead," Lewis told me bluntly. And that's why brain cancers like neuroblastomas and neurofibromatosis are still the leading cause of cancer-related death in people under the age of 35: the few remaining cancer cells soon migrate beyond the range of the slowly diffusing drugs.

At last fall's meeting of the Acoustical Society of America, Lewis presented a paper on the use of acoustic pulses to help brain tissue absorb chemotherapy drugs faster -- hopefully before the cancer cells have a chance to migrate very far -- and also increase the range of diffusion. He and his collaborators (groups at Yale and Princeton) are using focused ultrasound  to agitate the tissue matrices, enhancing permeability and making it easier for the drug to get into the brain tissue. Basically, they're massaging the brain tissue to open up the pores, since the brain is kind of similar to a sponge. (I held a "training brain" once while visiting a lab doing Alzheimer's research. It is indeed a spongy organ.)

Initial results from experiments with a horse brain indicate that with such a technique, the drugs do indeed spread further and faster into the tissue than they would by natural diffusion alone -- a hundredfold further, in fact, which makes it very promising for future treatment of brain cancers. They're now carrying out a full study using live animals to see if they still get enhanced diffusion effects, and also to make sure a living creature can withstand the treatment.

Ironically, Lewis got the idea from an Indian study on using sono-poration for transdermal drug delivery, an older technique in which the drug is applied to the skin, and then ultrasound  is applied which breaks down the skin surface so the drug can better permeate through. The Indian leather industry uses a similar technique to help dyes diffuse into the leather, resulting in a more uniform color. One of the things they discovered is that when surgeons remove the tumor and insert a drug disc into the cavity, there's a form of interface resistance that takes place, similar to surface tension on water. "It's because there's more tightly cohesive bonding between the cells at surfaces; they lock into each other," Lewis explained. "The sono-poration effect of ultrasound breaks down the interface and allows more rapid diffusion of drugs."

They're still not entirely sure what mechanism is actually at work in the technique. Some of Lewis's collaborators suspect that acoustic cavitation from microbubbles work to bloat the pores and open them up sufficiently so the drugs can diffuse through the tissue more effectively. Lewis thinks it might be primarily a mechanical effect related to the acoustic waves: "They go through the tissue as a compression wave, which oscillates the tissue and massages it to allow the drug more readily to diffuse through it." He likens it to how dentists will often massage a patient's gum when injecting Novacaine into the nerve because it helps push the drug around a bit to reach the nerve more quickly. "We're trying to rub the brain" using ultrasonic waves.

We want folks like Lewis and Nolte and the thousands of other researchers looking for new, improved ways to fight cancer to be able to continue with their work. One place to start is writing to Congress and complaining vociferously about the draconian cuts to science funding. Another is by participating in charity fund raisers like the ones offered by St. Baldrick's. Because someday, that cancer patient in dire need of cutting-edge treatment could very well be one of us.

cosmos: the untold story

It's been a whirlwind couple of weeks, and thus I am only now getting around to writing about the first "Journal Club" workshop on communicating science here at KITP. (You can find the audio/video and PowerPoint slides here, and a complete list of upcoming workshops here, if you're truly interested in the weird kinds of things I'm trying out to further the cause. Honestly? I suspect a couple of the more experimental workshops might bomb. I still think they're all approaches worth trying. One never makes any progress unless one is willing to take the occasional risk.) The theme was about "Finding Your Narrative: A Different Kind of Reductionism." I've learned over the course of my varied career that the trick to all good science communication is being able to boil a complicated science story down to its most basic components -- the "core narrative" -- to which one can then add layers of detail and complexity to tailor the narrative to a wide range of target audiences.

The main point I tried to get across in that first workshop is that this is not the same thing as the "dumbing down" epithet that many physicists like to fling at popular approaches to difficult subjects. That accusation stems from a misunderstanding about the process at work. It's fundamentally no different from the reductionism that drives most of physics: reducing the complexity of nature to universal fundamental mathematical laws that can be broadly applied to many different types of phenomena. The core narrative serves much the same purpose, providing the driving force behind every story. Don't underestimate the power of the core narrative! A large fraction of the broad appeal of the Harry Potter books stems from J.K. Rowling's skillful weaving of a narrative tapestry filled with every major literary archetype under the sun. (Just how many times did she read Joseph Campbell's Voyage of the Hero?)

This ability to identify the core narrative elements of any story is more important than ever, frankly, given how the media enterprise is simultaneously branching out into new multimedia formats and distribution methods, and seeking to integrate all of those into one cohesive whole. It's no longer just about the morning newspaper or the evening news anymore. The harsh truth is that those who are serious about effective science communication have to be more flexible and adaptable than ever. Online content has changed the ways in which we communicate, whether we're talking about the blogosphere, YouTube, wikis, Websites affiliated with newspapers, books, TV, and so forth -- yes, even PowerPoint lectures (TED talks, anyone?). Even if scientists have zero interest in communicating their research more broadly -- and that's entirely their prerogative -- the same set of skills will help them communicate far more effectively with their peers.

So anyway, I tried out this whole "core narrative" approach at my first "Journal Club" workshop, with the help of a few assembled KITP physicists. Specifically, I wanted to explore a potential narrative I latched onto, somewhat randomly, my first week in Santa Barbara, during a talk by Juegen Berges, who's visiting KITP from the Technische Universitat in Darmstadt, Germany. Like most of the technical talks here, the details were way over my head, but I could grasp the barest outlines sufficiently to realize that the standard cosmological model of inflation has a mysterious gap, and that gap needs fillin'.

First, a bit of backstory: the prevailing theory of cosmic inflation (at least partially supported by observational evidence to date) is that the universe started out as a singularity, popping into being thanks to a quantum fluctuation, and instead of having its short life perfunctorily snuffed out by its own strong gravitational field, it underwent a brief, very rapid period of expansion during the first fractions of a second of its "life" through one of those mysterious flukes of quantum uncertainty. (For those hungering for the details, there's an excellent summary for beginners by John Gribbin here, courtesy of Lawrence Berkeley Laboratory, although it employs the dreaded balloon analogy that the Spousal Unit loathes so deeply.)  

Inflation was first proposed in 1981 by Alan Guth to explain why our universe looks the way it does today. For starters, the universe apparently looks the same on opposite ends of the sky -- dubbed "the horizon problem" -- which indicates that those regions of space were once very close together. Second, spacetime is pretty much flat; the cosmos is constantly teetering on the edge "between eternal expansion and eventual recollapse," to borrow Gribbin's phrasing. Inflation explains how this state of affairs originated.

Now, I rarely cover theoretical physics or cosmology, so my knowledge is a bit, um, scatty on the details. Rather than boning up on inflationary theory to make a good impression -- I'm married to a cosmologist, it would have been so easy -- I opted instead to swallow my vanity and let my ignorance be displayed for the assembled physicists to see. This is tough to do, especially as a woman operating in a male-dominated environment, but I think it's important to do so when you're striving for better communication. It brings the level of discourse way down, for starters, and drives home just how wide the communication gap is between physicists and the general public. As an added bonus, it helped deepen my own understanding in the process.

For instance, I discovered that I harbored a fundamental confusion about the inflationary model that I suspect many non-scientists share: the Big Bang actually comes after inflation and the initial "birth" of our universe from a tiny singularity/quantum fluctuation. We have a prequel (inflation), and a sequel (the Big Bang), but the problem is, physicists don't really know what happened in between those two narratives. They know there has to have been a "reheating" period, because that's what provided the energy behind the Big Bang. But next to nothing is known about the actual mechanism by which this came about.

Don't take my word for it, either. Check out the Wikipedia entry: there's literally just a few sentences about this "reheating phase," to wit: "The end of inflation is called reheating or thermalization because the large potential energy decays into particles and fills the universe with radiation. Because the nature of the inflaton is not known, this process is still poorly understood, although it is believed to take place through a parametric resonance." That segment reminds me of the famous Sid Harris cartoon where two physicists are looking over a complicated equation, and at one point, the chalkboard simply reads, "Then a miracle occurs." One of the physicists comments, "I think you need to a be more specific here in step 3...."

So the cosmos has an untold story, at least so far as the general public is concerned. Why did I pick this particular narrative out of all the first two weeks of talks I attended at KITP? Well, the birth of the universe has broad appeal, so you don't have to cast about too hard for a compelling overarching framework. It's got a couple of those universal archetype story arcs: the classic "origins" myth, and also elements of a "coming of age" motif. Our main character is the universe itself, from the moment it popped into being as The Little Singularity That Could, and we proceed to follow its evolution as it develops into the mature cosmos we see today -- the Voyage of the Hero. Plus, there's a mystery as the story's central conflict -- how did our protagonist get from that tiny singularity to the vast, awe-inspiring cosmos we have today? ("The Universe: The Missing Years.") And everyone loves mysteries.

Finally, Berges is a good speaker, and when he was discussing the prevailing theoretical mechanism for reheating -- "parametric resonance," still very much a stub on Wikipedia -- he stopped briefly to demonstrate a simple pendulum motion (a classical physics example of parametric resonance), and explained that it was like the pendulum, with each pass, got a little extra "kick" of energy, which gradually built up to cause the reheating. So I had a visual element to grab onto. What can I say? It caught my imagination, and a tiny spark was lit. I wanted to know more. So that's what I picked as my focus for the interactive portion of my first workshop. (Scientists take note: it really can come down to something that basic. You must ignite that tiny spark in your audience and make them want to know more.)

In short, I had all the requisite elements to craft a compelling narrative. I just needed to flesh out the details -- which can be tricky when you're dealing with highly technical physics stuff, and even trickier when the physicists themselves haven't quite got a handle on the problem. But we worked through it, step by step, and slowly put together a workable framework. Once upon a time, there was a little singularity, plucked from short-lived obscurity by sheer quantum will and a bit of random luck -- a violent outward push that countered the more "natural" tendency to collapse out of existence, courtesy of a mysterious "benefactor."

And just what was that benefactor? Cosmic inflation! Guth's original inflationary model has since been improved upon, most notably by Andrei Linde, Andreas Albrecht, and Paul Steinhardt, among others, and there are now a bewildering array of inflationary models to choose from -- variations on a theme, if you will. See, Guth's original model didn't account for the critical reheating phase. (The shortest explanation is that the cosmic evolution decays through bubble nucleation, which doesn't generate radiation, ergo, no reheating.) So the three gentlemen mentioned above proposed an alternate model ("new inflation," or "slow roll inflation") in which inflation results from a scalar field (and associated particle) -- known as the Inflaton! -- rolling down a potential energy hill. Think of coasting downhill on a bicycle. As the hill becomes steeper, you roll faster and faster. Inflation occurs at the point where the hill isn't very steep, and ends when the slope becomes steeper. The extra energy acquired as the scalar field picks up speed gives rise in turn to reheating, setting the stage for another critical growth spurt: the Big Bang. Our protagonist has been expanding and maturing ever since -- apparently at a faster and faster rate.

That seems to be the prevailing thinking. And that extra "kick" of energy at the steepest point of the potential energy well is the parametric resonance. Another useful analogy for parametric resonance emerged during the discussion: a parent pushing a child on the swing. With each push, the parent matches the speed/frequency of the swing, and those energies add together, so the child swings higher and higher, getting extra infusions of energy rather than letting entropy run its usual course. (My question, naturally, when applied to reheating, is, who's doing the pushing for the cosmos? That's what physicists are trying to figure out.)

And thus, Berges' simple demonstration of a pendulum to illustrate parametric resonance has been transformed into a well-developed narrative framework, with (I'd wager) broad commercial appeal. In fact, I smell bestseller, with just a whiff of movie rights. I'm thinking high concept: Batman Begins for the cosmological crowd. Christian Bale could play the Inflaton, in black tights with a scalar field pattern and a giant "I" emblazoned on his chest, with Liam Neeson guest-starring as Parametric Resonance. That just leaves the casting of the Cosmos -- maybe Daniel Radcliffe of Harry Potter fame?

So that's what I learned in school these first few weeks: a crash course on the status of the inflationary model. I also cleared up some lingering confusion over the connection between electroweak symmetry breaking and the Higgs boson -- but that's a topic for another post. At this rate, I'll be talking like a physicist with the best of them, just in time for March 14.

by a whisker

Not all my time here at the Kavli  Institute is spent listening to talks about nonequilibrium dynamics and supersymmetry and such. We're practically next door to the UCSB Physics Department, which means I can occasionally nip on over to catch the occasional departmental colloquium. My first week in Santa Barbara, I heard a terrific talk by David Kleinfeld of the University of San Diego, who studies how rats combine motor and sensory signals in their tiny little rodent brains using an imaging technique known as an electromyogram, which records muscle movement. He's not the only one, either: in the last decade or so, there's been an explosion of research in this area among neurobiologists, for some very practical reasons. While the human brain is more complicated than a rat brain, there are some striking similarities. The hope is that learning more about rodent neural pathways will help scientists develop new treatments for brain-related disorders, like Alzheimer's (or stroke, or Parkinson's), and to design prosthetic limbs that can be directly controlled by one's thoughts (technically by the electrical signals the brain uses to communicate -- not some weird kind of psychic ability).

Scientists have been playing with rats in the lab since the early 1800s, starting with simple mazes and teaching them to tap on levers. Now they're using them to try and solve one of the most fundamental questions of perception, in both humans and animals: how do we know where objects are in relation to our bodies? It turns out that rats have an unusual means of navigating: their whiskers, or as Kleinfeld calls them, vibrissa. Rats have about 30 large whiskers and dozens of smaller ones. They're part of a surprisingly complex "scanning sensorimotor system" that enables the rat to perform such diverse tasks as texture analysis, active touch for path finding, pattern recognition, and object location, just by scanning the terrain with its whiskers.

Sure, the whiskers are just hairs, a collection of dead keratin cells, much like human hair. It's what they're attached to that make them useful, and as sensitive as human fingertips. Each rat whisker is inserted into a follicle that connects it to "barrel" made up of as many as 4000 densely packed neurons. Together they form a grid or array that serves as a topographic "map," telling the rat's brain exactly what objects are present, and movements that are taking place, at any given place and time. All those barrels in turn are wired together into a kind of neural network, so the rat gets multidimensional cues about its environment. As it moves across  the terrain , a rat is constantly scanning its surroundings with its whiskers, sweeping back forth between five and 12 times per second (i.e., between 5 and 12 Hz). When a whisker hits an object, it bends in its follicle, and this sets of an electrical impulse to the brain that enables the rat to determine both the direction and how far each whisker moves. That's how the animal senses its environment and forms an "image" of the world around it.

Basically, the rat whiskers trigger nerve signals that the brain decodes. How does the brain do this? Apparently through a feedback loop that is very similar to that created by an FM radio's circuitry, which generates an intelligible signal by comparing electrical patterns from an oscillator to those from incoming radio waves. For instance, certain neurons in the rat cortex pulse at very precise frequencies (near 10 Hz), and these pulses are sent continuously to the thalamus, which compares them with incoming whisker signals. Instant decoding!

In 2003, scientists discovered that a rat's whiskers are also used for hearing, because they resonate at certain frequencies. It's the same principal that applies to the strings of a harp, or a piano, or a guitar: longer whiskers resonate at lower frequencies, while shorter whiskers resonate at higher ones. (For instance, one particular whisker was found to vibrate at 182 Hz, which corresponds to a musical note between F and F#, below middle C.)

Rats have shorter whiskers near the nose, longer ones further back, and this enables them to create a kind of "frequency map" by poking its nose all over the place. A single whisker acts much like a single-pronged tuning fork. Put them all together, and a rat can sense size, position, the edges of objects, even slight variations in texture, relative to its little rodent body. For instance, a very fine texture would set up a stronger vibration in a high-frequency whisker than it would in a low-frequency whisker.

Kleinfeld's team has taken things one step further, trying to determine where the input signal is coming from: for instance, is the rat actually "listening' to the electrical impulses generated from the whiskers (reafferent) or is it using a copy of this sensory information for processing (efferents copy)? and how the heck can scientists figure this out? The first step is to simplify the system to isolate one particular whisker attached to a "barrel" of neurons.

Kleinfeld solved the problem by essentially removing all but one of a lab rat's whiskers to see just how sensitive this system is. He admits the rats find this "very upsetting" --  how would you feel if you lost most of your means of sensing your surroundings? -- but like human brains, the brains of rats can adapt to even drastic changes. In the 1970s, scientists learned that removing even a single whisker in the first few days of a rat's life would affect its ability to learn and function, but the animal would soon adapt -- much like someone born with only four fingers quickly adapts to what might be a major adjustment if it happened in adulthood. But all the whiskers? That's like losing everything except your big toe. How much can a rat really sense with so much of its system depleted?

Rather a lot, it turns it, in part thanks to those nested loops that comprise the vibrissa sensorimotor system, proving many levels of feedback. Kleinfeld found that the rats could distinguish angular position, relative to their faces, even with a single vibrissa. Once this had been established, he was able to numb the nerve with Lidocaine to temporarily block the signal -- but only on on side. The signal was successfully blocked, which seems to be a pretty clear indication that rats depend predominantly on an outside signal (the reafferent model). 

Ah, but wait! The whole efferent (or central) copy theory seems to supply information regarding amplitude -- an internal signal source, rather like a built-in calibration system. And we all know how important proper calibration is for any measure device or system. So you've essentially got two incoming signals that interact, with one signal modulating the other like a circuit switch, and together provide the rat with its impressive powers of sensory navigation. Kleinfeld admits that this particular insight is closer to conjectural than an actual proven hypothesis. The next step in his research to to look for the kinds of neural cells and circuitry in the rat brain that could comprise such a system design.

That was the gist of Kleinfeld's talk. It seems to dovetail nicely with a 2004 experimental result conducted by researchers at the Max Planck Institute for Medical Research in Heidelberg, Germany, in which they found that activating a single brain cell in a rat could make its whiskers twitch. They used tiny electrodes to excite those individual neurons in the motor cortex of rats (mercifully anesthetized). It just so happens that the motor cortex doesn't control muscle movement directly. Rather, it signals a pattern generator, and this in turn sends the detailed commands to the muscles.

Who knew rats were such complicated creatures? It seems like such a simple strategy, little more than a sweep of one's immediate surroundings, but the animal manages to collect and process a staggering amount of sensory data about objects, textures, and so forth -- all by a whisker.

built for speed: part deux

Today we bring you Part Deux of our awesome Q&A with Diandra Leslie-Pelecky, a physics professor at the University of Nebraska, Lincoln (in the process of relocating to Dallas, Texas) and author of The Physics of NASCAR: How To Make Steel + Gas + Rubber = Speed. If you missed it, you can read Part I here. Also check out her Website and schedule of speaking engagements. And oh yeah -- buy the book!

Q: As a woman in physics, you're sensitive to gender dynamics, and NASCAR is another male-dominated sport. Did you notice some differences?

DLP: I'm so used to being one of the few women in a room that the composition of the NASCAR garage and shops didn't strike me as unusual. NASCAR is a little more male dominated than physics, but I think the bigger difference is between non-profit academia and a for-profit, high profile professional sport. I have yet to see young women waiting anxiously outside the door for the speaker after a particularly good talk at the APS March meeting. [The Spousal Unit would like readers to know that he heartily approves of the concept of physics groupies, and thinks this should become de rigeur at conferences. In fairness, he believes that female speakers should have groupies, too.] The fact that all the drivers are male and there are very enthusiastic female fans changes the male/female dynamics significantly compared to a situation in which it is assumed that everyone is there -- male or female -- for their job.

The people who work in the shops and the garage (and the NASCAR officials) are a much more diverse group than the drivers.  There are a number of women working for NASCAR in the technical inspection line, and during races in the pits. There are a few women on the garage and pit teams, but not many. I went to my first testing session in Vegas a couple of weeks ago and was pleasantly surprised to find a number of women engineers. Some come to the track only for testing, when the teams are allowed to use data acquisition tools on the cars. I had only been to races, and many of the women I saw at Vegas work primarily at the shop.

The garage environment is a little like a frat house. There are a lot of practical jokes and put-downs and a lot of "guy humor." The environment in the engineering departments of most shops may be a little more professional. (I realize that sounds like I'm comparing research-intensive universities with frat houses. I'm not, but I do think many research universities tend to be more competitive and less collegial.) NASCAR is also very high pressure, because if you are, for example, on the pit crew and you screw up, you do it in front of millions of people and it could literally cost tens or hundreds of thousands of dollars.

Physics is a little ahead of NASCAR in terms of numbers, but there are a lot of similarities. The most important thing, I think is early parental involvement. If you talk to most women in science, they will tell you they had extremely supportive parents. The same is a requirement for racing, especially because racing is expensive. Kids get involved at age 7 or 8 in go karting, and advancing up the ranks isn't cheap. The prospect of getting physically hurt is a bit of a difference between science and racing. I'll stick with a theoretical understanding of impulse, thank you.

Q: One of the strengths of your book is that it brings a strong narrative structure to a story in which, as you once told me, "the main character is momentum." Why did you decide to do that, and what can other scientists learn from this about effective ways to communicate with broader audiences?

DLP: The narrative structure just seemed to work as a way to take the reader along with me on the trip. I'd love to say I planned it that way, but the end book I delivered to Dutton was very different than the one I expected to write. I sort of fought the narrative structure at first. For example, it was really hard for me to write physical descriptions of people. First, I often realized after I left an interview that I couldn't actually remember what the people looked like and I was so focused on the science that I hadn't written anything down. Second, I felt uncomfortable writing that someone was graying, or heavy, or balding. And the longer I was around the garage, the more I couldn't help but feel for the people I was watching. I couldn't write dispassionately about the struggles the No. 19 team was having last year, or the disappointment Andy Randolph felt looking at the blown engine from Fontana.

I went to a screenwriting workshop called Catalyst and the most important thing I took away from that is that there has to be something your audience cares passionately about. That almost always involves people. Science isn't done in a vacuum. (Okay, technically, it is, but I meant there is no science without the people doing it.) The thing that scientists and the NASCAR people have in common is passion. Passion allows you to work 60 hours a week without realizing that you're doing it. The Physics of NASCAR shows people that science doesn't just happen in laboratories.

Q: Who is your target audience?

DLP: My book is meant for the NASCAR fan who doesn't know a lot of science, or the science fan who doesn't know a lot about NASCAR. The writer Margaret Wertheim pointed out that people who are already interested in science are very well served. It's the people who don't know that they're interested in science that we fail. NASCAR has 75 million fans. If this book gets even a very small percentage of them to think about taking a science course, or ask their teacher about springs, I will be thrilled. My goal is to stimulate people's interest. They'll learn some science from reading the book, but I hope the book will inspire them to look further and ask their own questions.

I think we often miss that what is interesting to us as physicists is not at all interesting to most people. Students usually have three questions: "Why do I have to learn this?", "When am I ever going to use this?", and "Is this going to be on the test?" We usually only have a good answer to the third one. How can you have a position about alternative fuels if you don't understand how an internal combustion engine works? Every year, I talk to my students about engines in the thermodynamics unit, and I talk about real engines. Inevitably, I get a few students who will email me and ask, "If the internal combustion engine can never be really efficient, why aren't we looking for alternatives?"

You don't have a right to have an opinion on things you don't understand. If you can't explain what a stem cell is, you shouldn't be lobbying for or against using them. We need to be teaching students the science they need to function in today's world. 

Q: Have any of your physics colleagues expressed dismay about taking such a "popular" approach? It's a common criticism of such books. How would respond to that criticism?

DLP: I blame it all on NSF and NIH. If they funded more of my research proposals, I would be so busy in the lab that I wouldn't have time to write about NASCAR. I've been bombarded over the last few weeks with pleas from the scientific societies to write my elected representatives because the US budget for science this year is a disaster. Those of us in schools from kindergarten to universities are responsible for the people who made these decisions.

Look at people like Leon Lederman and Carl Wieman, who stopped doing physics research per se and are focusing on education issues because they believe that solving these problems is more important than publishing another paper in Physical Review (sorry Phys. Rev.). When you get to heaven, St. Peter is not going to ask for your academic C.V. It's an important enough problem that what other people think or say isn't really a factor.

I've been working with teachers from elementary to high school for more than 10 years and frankly, I'm frightened by much of what I see there. Even the best teachers are paralyzed by the implementation of the idea that we can prove that students are competent at science by giving them multiple choice vocabulary tests. We are teaching kids that learning is nothing more than rote memorization of unrelated facts they will never use again. They get to college or the workforce and are shocked to find that your results and not your intentions are what matters. They can't write persuasively. They can't read a chapter from a book and pull out the main ideas. The best of our students will be the best in the world, but I fear that the distribution is getting broader and broader. We are not doing well by the majority of the students we educate and, in the end, it is going to come back and hurt us as a country.

I've gotten a lot of encouragement from my colleagues at Nebraska. That may be because we have a long tradition of writing books about the physics of sports, starting with The Physics of Golf by Ted Jorgenson, The Physics of Football by Tim Gay, and now my book. We're taking bets on which of the current crop of assistant professors is going to be writing The Physics of Professional Wrestling in a few years.

Q: You've written The Physics of NASCAR which -- if there is any justice -- should be a huge success. What's next?

DLP: My father's favorite saying was, "Life is not fair." So I'm trying not to get any expectations up. My next writing projects are going to be research grant proposals. I'm hoping that my experience writing this book has made me a more convincing proposal writer as well.

I just wrapped up working on a television program on the science of the new car for VOOM HD networks. That project is headed up by Brad Minerd, who did the spots with my colleague Tim Gay for NFL Films. Brad is now at NASCAR and gave me the opportunity to consult on the show. It was a really interesting experience to see how television programs are put together. It is even more of a challenge to put science into a very short TV program than it is to write a [popular science] book.

As for a second book, I've heard from F1 racing people talk about finding ways to harness the innovative minds of the people in motor sports to generate ideas that could be used in consumer automobiles. For example, limiting how much gasoline the team gets for a race would force them to think about ways to capture some of the energy from the engine that is normally wasted, such as the motion of the flywheel, or heat.

As a country, we have to make some really tough decisions about energy, and I don't think most people have the information they need to make an informed decision, so I'm thinking about how there might be a way to do something along those lines. I also have an idea for a NASCAR-themed romantic comedy about an aerodynamics engineer who falls in love with a NASCAR driver. It seems like a healthy challenge to get the Navier-Stokes equations and a kiss in the same line of dialogue!

built for speed: part one

It's a very special day at the cocktail party, because we're featuring an extensive Q&A interview with Diandra Leslie-Pelecky, mediagenic condensed matter physicist  extraordinaire and author of a terrific brand-new book: The Physics of NASCAR: How To Make Steel + Gas + Rubber = Speed. It's so extensive, in fact, and so substantive, that we're splitting it into two parts: Part I (this post) focuses on some of the actual science behind the sport and her adventures hobnobbing with the NASCAR crowd. Part II will be posted tomorrow and will focus on the broader issues of gender dynamics, effective communication of science to diverse audiences, and making NASCAR vehicles of the future more energy efficient.

This book's publication is particularly gratifying because I've known Diandra for years. We met at an academic/industrial workshop sponsored by the American Institute of Physics sometime in the 1990s, hit it off -- it helped being two young women of roughly the same age in what was usually a roomful of men -- and over the years became good friends, despite living in completely different parts of the country. And it's always gratifying when one's friends do well.

We've had lots of long dinner conversations over the years about physics, and communicating physics to broader audiences, but I distinctly remember one in particular, just after my first book came out. Diandra mentioned that she'd been thinking a lot about the underlying physics of NASCAR racing, and thought it might make a decent book. "You should totally write that book!" I exclaimed, recognizing (as did she) that it could potentially reach people who would never otherwise have any exposure to physics. I say that a lot to people who have ideas for books; it rarely translates into concrete action. (People have lives, after all, and writing a book is an enormous time- and energy-suck. It can literally consume you.) Blessed with an unusual degree of decisiveness, discipline, and drive, Diandra promptly went out and wrote it.

And she wrote a damned good book, too, packed with fascinating science illustrated by real-world crashes, wins and losses, and colorful anecdotes gleaned from all her backstage visits and interviews with the mechanics, drivers, car designers and so on. She gives a rare peek at how much effort, ingenuity, and just plain good science goes into this seemingly inane sport. I used to catch bits of NASCAR races on TV while flipping through channels, and marvel at how so many people could be so enthralled by a bunch of cars going around a track really, really fast. I get it now. At least a little. There's a lot more to NASCAR than circling around a track. Don't believe me? Buy the book and see for yourself; I suspect you'll get sucked in, just as I did. Check out her Website, and her schedule for speaking engagements. And join me in welcoming Diandra to the cocktail party!

Q: What is it that sparked your interest in writing a book about NASCAR physics? Were you just a really big fan of auto racing?

DLP: I was flipping through channels one Sunday and happened upon a race. Nothing exciting, just a pack of five or six cars going around a turn. I was ready to click to the next channel, but before I could, one of the cars in the pack -- all of a sudden, and for absolutely no apparent reason -- hit the outside wall. I'm a physicist. I know that things don't happen without a reason, so this bothered me a little.

No one was hurt but the car that hit the wall took out a bunch of other cars, so they had a bit of cleanup to do. That gave me time to watch the replays. I saw no tire problems, no engine problems, no contact with other cars. The announcers said something about the car "getting loose" and the other car "took the air off his spoiler." I felt the way I suspect my students feel when I start using physics jargon.

I got on the web, thinking I'd have an answer in 10 minutes. Two years later, here's a book about it. I've always liked writing and I've always liked teaching, but over the last few years, I had really gotten down about teaching. It is very frustrating teaching students who don't want to be there. That's partially our own fault because we do a pretty lousy job showing people that physics has to do with things they care about. When I explained things in class using NASCAR, or even cars in general, the students were more engaged because they could see the connection between what they were supposed to be learning and what was actually happening around them. There are very few other sports in which the link between science and winning is as strong.

The moment of conception for the book goes back to a conversation you and I had at an American Institute of Physics Industrial Affiliates meeting in Bethesda, Maryland in 2005. [Jen-Luc Piquant observes that Diandra has a far clearer, detailed memory of date, time and place than I do.] I mention this because we often forget that what we say to other people has great power. Sometimes a word of encouragement is enough to turn a wild dream into a plan.

I had been thinking about NASCAR and using it to teach physics all summer and mentioned it to you because I'd always harbored this abstract dream of being a writer someday. We are the same age, and I think we had been talking at our table about milestone birthdays. You told me to "Just do it" and sent me one of your book proposals and a referral to an agent. I sat on it for six months, then contacted the agent and figured that it would take a year or two to sell -- if it sold at all. Much to my surprise, it sold rather quickly. Then I actually had to write it!

Q: So what caused that crash you saw on TV?

DLP: The grip of each tire is proportional to how much force is pushing down on that tire. You can get grip two ways: mechanical grip, which is the interaction of the tire and the track, and aerogrip, which is due to air molecules rushing past the body and pushing down on the car, which again pushes the tire into the track. Without aerogrip, you have to slow down around the turns. The amount of aerogrip depends on how fast you're going and how other cars disrupt the airflow around you. If a car comes up behind you just right, they can decrease the amount of air hitting the rear of your car, which decreases how much grip your rear tires have. The car I saw crash lost rear grip and couldn't slow down enough to make the turn.

Q: You had the opportunity to go behind the scenes and interact with the drivers, owners, mechanics, and various others who make NASCAR happen. What were some of the highlights of researching the book?

DLP: The book turned out much differently than I expected because I went into it thinking that I'd talk to the technical people to get background and then write up chapters explaining different topics. I thought the technical people were just in the race shops, but the race track garage is filled with science.

I went to a meeting of the Society of Automotive Engineers Motorsports Conference -- at this point, I didn't know a suspension from a carburetor -- and I met people from F1, Indy racing, drag racing and NASCAR. They were more than happy to answer my questions and they were very welcoming of a total outsider into their group. Not all professional societies are like that.

Josh Browne, who was the No. 19's Crew Chief at the time, was at the conference and I invited myself to "embed" with their team for a couple of races. Josh understands the potential power of using motorsports to get people interested in math, science, and engineering, and he has been (and continues to be) incredibly supportive. The guys on the No. 19 team let me follow them everywhere, ask a lot of questions, and made sure that I didn't get run over in the garage.

I was surprised by the access I was given, both at the track and in the shops. I was upfront with each team that my goal wasn't to spill their secrets, and I got a lot of great stories that ended with, "Oh, please don't publish that!"

Q: You also got to drive one of the race cars, thereby earning the envy of teenaged speed demons everywhere. Inquiring minds want to know: how cool was that?

DLP: The Team Texas High Performance Driving School at Texas Motor Speedway made that a great experience. You have to understand that I'm afraid of basically everything, especially things that I've never done before. Team Texas puts ten cars on the track at a time and each car has an instructor in the passenger seat. I picked Team Texas because I liked the idea of having someone right there, and because they offered the opportunity to do a driving experience and then a ride-along with one of their instructors. I figured if I didn't get the car over 100 MPH myself, I'd at least get the feeling of speed from the ride-along.

I was surprised because I wasn't that nervous waiting for my turn. It's because I was focusing so much on how I was going to capture that experience and all the subtleties for the book. I was concentrating on the track and the signals from the instructor, and I was a little disappointed when we finished and pulled into the pit road because I didn't think we had gone very fast. Paul, my instructor, told me I did a pretty good job for a first tie, and that we had hit the max speed: about 150 MPH. I have a videotape taken from the car, and when I went back and watched, we had passed just about all the other cars on the track. There is an ignition chip that limits the engine rpms, which limits the speed. When I went back to the in-car tape, I could hear when the chip kicked in, which is called "hitting the chip."

I rode with Mike Starr, who owns the Team Texas Performance Driving School. For anyone thinking about doing a ride-along at Team Texas, let me note that when you own the school you get to run in the lead most of the time. The difference between my driving and his driving is that I was doing 150 MPH down the straightaway. Mike was doing 150 MPH around the turns. I thought my head was going to go right out the passenger window -- we were pulling about 2g! While we were driving, they kept the cars pretty far apart, but when we were passengers with the professional drivers, we were going 150 MPH and I could literally have reached out and touched the car next to us. Way cool.

When I got out, I was fine, but after about a minute, I felt like I had drank a whole pot of coffee. My legs were wobbly and my heart was racing. My hands were actually shaking. I thought that maybe my body had finally caught up with my brain and was appropriately afraid.

When I was with the No. 19 team at Atlanta for qualifying, our driver (Elliott Sadler) was one of the last to go out, and he ended up with the second fastest time. While we were waiting for the other cars to finish, I noticed that Elliott was shaking the same way. Josh told me it's adrenaline. It's like winning in Vegas: you get a rush and you want to do it again.

Q: Was there anything that surprised you about the world of NASCAR?

DLP: Almost everything surprised me about NASCAR. In academia, we talk a lot about how open-minded we are, but we all have stereotypes, especially about things that are outside our immediate experience. I had my own stereotypes of NASCAR and most of them were totally wrong.

I was pleasantly surprised by how helpful everyone I worked with has been. I started talking with people like Eric Warren and Andy Randolph, both of whom are PhDs (in aeronautical and chemical engineering, respectively), so we had the common background of having been through the hazing experience known as graduate school. (In both interviews, we ended up talking about funding. Put any two PhDs in a room and they talk about funding.) At my first race, I spent most of my time with Josh and Chad Johnston, who are both formally trained engineers. By my second race at Martinsville, I had screwed up enough courage to pester the mechanics in the garage. That sounds like an upside-down approach, but that's the way it felt most comfortable to me.

NASCAR is largely a meritocracy. If you go to people unprepared, they'll let you know (just like in physics). If you ask intelligent questions and are upfront, they'll be exceedingly generous with their time. No one was ever condescending or rude.

I went into the project thinking this would be like an anthropological expedition: I would stand in the back and take notes and report what I saw. And I guess that's exactly what I started out doing, but what I saw were people passionate about their jobs who work 60-80 hour weeks because they are obsessed with figuring out how to make their car go faster. In other words, people like scientists, except they make better money than we do.

I remember standing on top of the hauler in Atlanta -- it was March, and very, very cold. It was my first time at the track and I hadn't yet gotten the nerve to venture into the garage per se. I could see the track from the top of the hauler, and if I ducked down, I could see into our garage stall. The team wasn't having a great practice, and I remember in particular one time they had rushed to make a change to try to make the car better. The entire crew was standing in the empty garage stall waiting. The driver (Elliott Sandler) came over the radio after a lap and said, "Nope. Not any better." I could hear the disappointment in Elliott's voice and I remember watching Kirk Almquist (the car chief) from the top of the hauler, and seeing his shoulders slump and his head hang when he heard that. You can't watch people who care so much about what they're doing and not be pulling for them to succeed.

Q: You've said that NASCAR drivers are "intuitive physicists." What do you mean by that?

DLP: Drivers can explain impulse and conservation of energy, but they don't use those words to do it. When it comes to racing, drivers are experimentalists and I'm a theorist. How many times have I calculated the centripetal acceleration around a banked curve? You get a number and it's mostly meaningless. You write it down and move onto the next problem. But I have a gut-level understanding of what 2gs feels like now.

Most drivers don't recognize that they are explaining "physics." I have a tape of Elliott explaining his 2003 Talladega accident (a quintuple somersault with two pirouettes and an upside down landing) that I used in my class. [Jen-Luc found a video clip of the accident here, as well as a clip of the all-time worst NASCAR crash to date, for all you morbid rubber-necking types... like her.]  It looks like a very serious accident, but Elliott walked away with literally nothing more than the wind knocked out of him. Elliott explains on the tape that, because he slowed down over a period of time, each hit dissipated a little bit of energy, and he felt a little force, but nothing like he would have felt had he stopped all of a sudden. Well, that's F=dp/dt in physics language. Elliott was surprised to find out we were team-teaching physics.

Jeff Gordon did an ESPN Sports Figures episode in which he explained the difference between kinetic and static friction. When you're going around a turn, you want to slide a little in the radial direction, but you can't slide so much that the car loses grip and heads into the wall. When the car starts sliding up the track, you're in trouble. Jeff says in the tape that his job is to detect the change from static to kinetic friction. He may not have known the words prior to taping, but I guarantee you he can feel the difference between those two types of friction through the seat of his pants in a way that most of us who can write the Lagrangian equations of motion for a race car cannot.

Q: Were you ever tempted to just buy a junker and take apart the engine to see how it works?

DLP: I lucked out having met Dr. Andy Rudolph, who is the Engine Technical Director at Bill Davis Racing. I visited him just after the spring Fontana race, where their No. 22 car's engine had blown up. The engine was in pieces sitting on a cart. The oil pooling around reminded me of blood. Andy was looking at it like a doctor whose patient had left the hospital looking perfectly healthy and now here he was doing an autopsy.

Engine books often show an exploded view of the engine. I got the literal exploded view of the engine, which helped me understand the relationships between the pieces better. The first time I talked with Andy, I didn't even realize that they use pushed engines, but he is a really good teacher, so I think I've got a halfway decent understanding of the engine. [Jen-Luc sez check out this photo of Diandra lookin' all cool and mechanical in the garage with Andy Randolph. You can just hear them saying, "Assume a spherical tire..."]

One of the great things about the people I met is that I'm still in contact with many of them. When they changed the size of the restrictor plate at Daytona, I sent Andy an email that was essentially my understanding of the changes, followed by, "Is that right?" He replied, "Yes, but..." and proceeded to show me another level of science I hadn't thought about.

A NASCAR engine works pretty much like a standard internal combustion engine. What really made me crazy was trying to understand the suspension -- the shocks, springs, weight distributions, etc. The suspension geometry is unique to stock car racing. NASCAR just changed car models, so the old cars, which can't be used anymore, were being sold off "pretty cheap" (meaning tens of kilobucks). I pondered getting one just to be able to understand the suspension a little better, but I'm sure there's a zoning regulation about having a car body without an engine in it sitting in your front yard. I could probably swing buying a chassis, but an engine is likely beyond the budget of an academic.

a little light housekeeping

[UPDATE: Many thanks to the commenters who pointed out the broken links. They should be fixed now. In my defense, I frequently wrap up blog posts late at night, when I'm a bit punchy from working all day. Oh, and for those interested in hearing my first KITP session, on "Finding Your Narrative," it's been posted at KITP's Website, in several different formats. (They tape all their talks, in fact.) I had trouble getting the video to stream smoothly, but maybe you'll have better luck. There's also the option of just an audio Podcast. The accompanying PowerPoint slides should be posted on Tuesday or Wednesday at the same place.]

Every now and then, it's necessary to engage in a bit of bloggy housekeeping and clear out the flotsam and jetsam that's worth mentioning, but somehow doesn't quite work into a full-length post. This is one of those times. I offer the following miscellany:

Bloggy Endings and Beginnings. Oh noes! After a whopping 2624 posts, Angela Gunn has shut down her TechSpace blog at USA Today. Howls of anguish reverberates through the science blogosphere at the news, only to be quickly replaced by cheers, because she's started up a new blog, Science Fair, that promises to combine the best of TechSpace with new lively innovations, not just from the Divine Miss G. herself, but also a handful of talented supporting writers. Jen-Luc Piquant sez check it out!

Celebrity Physicists on TV. It's been a big week for big-name Boston-area physicists (h/t: Peter Woit). First, MIT physics professor Peter Fisher did a guest stint on Conan O'Brien, performing an experiment on how long Conan's wedding ring would spin on the desktop. [Blake Stacey has the actual video.]  Second, Harvard's Lisa Randall (and author of Warped Passages) appeared on The Colbert Report, chatting about extra dimensions. Both these shows routinely have fun with physics (and physicists, when they're willing). Everyone remembers the classic appearance by Jim Carrey a year or two ago, in which he and Conan discussed quantum mechanics and Penning traps -- based on work by Harvard's Gerald Gabrielse. I learned today that Carrey also appeared on Conan's show in 2003 and staged an on-air phone call with Stephen Hawking (who claimed he was watching Carrey's movie Dumb and Dumber) to discuss new cosmological models. Classic! We need more people like Carrey willing to find the humor in science, and more scientists willing to play along occasionally.

Talk Like a Physicist Day! Long-term guests of the cocktail party know I've tried for a couple of years now to drum up enthusiasm for an official "Talk Like a Physicist" day -- kind of like the annual Talk Like a Pirate Day. I've been quite negligent about pursuing this, but fortunately, others have been more diligent. There is now an official blog devoted to the very first Talk Like a Physicist Day on March 14, 2008, with a logo and FAQ in the final stages of development. (There's already numerous short fun posts, including a series on Thursday Threads, for those committed to amassing a vast physics-themed wardrobe.)  I hereby invite my fellow physics bloggers to start promoting the occasion, ad coming up with ideas of whimsically creative ways to celebrate it. BTW, March 14 is also Einstein's birthday, and International Pi Appreciation Day. Check out this sketch by the Upright Citizen Brigade -- a spoof of 1970s educational show ZOOM! -- all about the value of pi. (Thanks to regular reader Justin Purnell for sending me the link.)

KITP Kommunique. Of course, the bulk of my time these days is being spent at the Kavli Institute of Theoretical Physics in Santa Barbara.  Everyone here talks like a physicist every single day; the challenge is getting them to drop the jargon to talk to regular folks in plain English. The KITP, for those who don't know about it, is a unique academic model: there are very few permanent scientists here. Rather, there are special programs organized around specific hot topics in theoretical physics -- planned years in advance, in many cases -- and the institute invites leading scientists in those areas from all over the world to spend anywhere from a week to a few months in residence. (Among other things, this makes me pretty much the dumbest person here when it comes theoretical physics; the collective brain power is awe-inspiring.) Right now, there's a program on Nonequilibrium Dynamics in Particle Physics and Cosmology (just winding up), and another on the physics of the Large Hadron Collider (just starting up). If past programs are any indication, at the end of both, there will be a flurry of cutting-edge technical papers appearing in the peer-reviewed literature, based on all the conversations going on here right now.

But the KITP is also committed to fostering scientific communication. That's where I come in. Each Friday through April 26th, I'll be presiding over a "Journal Club" meeting focusing on some aspect of communicating science. This week is all about "Finding Your Narrative" -- the core narrative that lies at the center of any good science story. It's a common experience among science writers to spend 30 minutes or more listening to a physicist describe his or her research in impossibly advanced terms, and in a disorganized fashion, while we try desperately to find that kernel that will sprout into the core narrative for the story we end up writing. This happens so frequently because, well, the scientists already know the story; they're right in the middle of it, so they start their "narrative" in medias res, forgetting that the science writer might not be quite as embedded in the story line. The narrative has been going on, from their perspective, for years and years.

It's a bit like a hardcore fan of Battlestar Galactica (or Buffy the Vampire Slayer) who's been avidly following their favorite series for several seasons and discussed every minute detail at great length. Someone trying to join the party that far into the story is going to have a whole lot of questions, and won't be able to keep up with the ongoing discussions very easily. The underlying concept for the very first session is a type of journalistic reductionism: if we can boil the topic down to the most basic ideas -- the core narrative -- it then gives us a strong foundation to add layers of more detail as needed for different types of media formats and audiences.

So tomorrow, after a brief introduction, I'll be taking one example from the program on Nonequilibrium Dynamics -- the latest theoretical work on the reheating phase of the universe's evolution per the inflationary model -- and detailing how far I've gotten this past week in finding the core narrative to pitch an actual written article about the subject. Because I want every single workshop to be interactive -- nobody learns communication skills by passively listening to someone lecture about it -- the participants (assuming someone shows up) will work with me to flesh out the remaining details, hopefully learning a few tips on how to do the same on their own.  Then we'll do something similar for the LHC program -- actually a tougher task, because there's already been so much media coverage of LHC physics, and we're kind of in a holding patten until the machine turns on later this year and scientists start getting data. We'll have to ferret around in the nooks and crannies to find an interesting new interim angle to construct a compelling narrative.

There will be blog posts on all of this, oh yes, so stay tuned. I've got a whole series of 10 workshops planned, exploring various media formats and how to tailor one's communication approach for different venues and target audiences. We'll be exploring Science Blogging 101, naturally, and practicing mini-press conference presentations, as well as on-camera interviews with the aid of a video camera and a few of my fellow journalistic sorts. As people get comfortable with the level of interaction, we'll get more ambitious, including stealing a page from Alan Alda's playbook and bringing in an actor/drama coach to run us all through a series of improv exercises. We'll even have a session on the interaction between technical consultants and TV writers, "Inside the Writer's Room," during which we will try to come up with a plausible concept for a physics-centric TV series -- just in time for Talk Like a Physicist Day! And finally: PowerPoint Karaoke! Okay, maybe not, unless I want to lose willing participants in droves. But it's a great idea, especially if some of our specialty physics cocktails are involved. [UPDATE: I've decided to go ahead and do the PowerPoint Karaoke, using it as a jumping off point for a discussion of communicating across disciplinary boundaries.]

The Holiday People Love to Hate. And finally, we all know it's Valentine's Day today. For those who missed it, last Saturday, the Spousal Unit and I teamed up for a special "Science Saturday" V-Day edition of BloggingHeads.TV. Otherwise, we mutually agreed not to officially celebrate this particular holiday, mostly because, well, it's so much nicer to surprise one's loved one constantly throughout the year with small thoughtful gestures. Making it an obligatory holiday kinda spoils the fun for us. But it's not an official boycott or anything, so that won't stop me from posting an amusingly mushy "Science-Themed Valentine" (h/t: Chad at Uncertain Principles) in his honor:

tunnel vision

Stanford physicists are apparently marching to the beat of a nanoscale drummer these days, according to a paper in the February 8 issue of Science. Yeah, it's a bad pun, but Jen-Luc Piquant couldn't resist. And I couldn't resist writing about research that combines acoustics, scanning tunneling microscopes (STMs), and resonance at the quantum/nanoscale -- particularly in light of a special session at the upcoming APS March Meeting in New Orleans celebrating 25 years of the STM, now a workhorse technology in all kinds of scientific fields, even beyond physics.

But first: quantum drums! The Stanford experiment arose out of an interesting acoustical question: do drums of different shapes always produce unique sound spectra (in terms of the properties of the acoustical wave)? It would be great if they did, because then it might be possible to develop an acoustical version of spectroscopy -- another workhorse physics-based technology that, say, analyzes the various elements that make up a distant star by studying the spectrum of light associated with that star. (It can also be useful for more terrestrial experiments, such as determining chemical composition of substances. They're always performing spectroscopic analysis in the lab on C.S.I.)

Sometime in the 1990s, alas, mathematicians proffered definitive proof that two differently shaped drums could produce the exact same sound, thereby dashing hopes of what I will call, for lack of a better term, "acoustical spectroscopy." This makes it impossible to work backwards from the sound spectrum to derive information about the physical properties of the drum that made that sound, because it does not have a truly unique signature -- rare, perhaps, but not truly unique. Spectroscopy works because there's only one answer to the question, "What is this stuff?"

Some people might deem this a failure, and relegate the topic to the dustbin. But this is science, people, where even null results can yield useful insights. Such was the case for Stanford physicist Hari Manoharan, who saw not a failure, but an opportunity, in part because, as he said in the official press release, "This revolutionized our conception of the fundamental connections between shape and sound." And it could even be relevant to spectroscopy, "because it introduced an ambiguity." As systems get smaller and smaller, and move into the nanoscale realm, quantum effects hold sway, and that tiny degree of ambiguity -- unimportant in the classical world -- suddenly could have a significant effect on, say, nano-electronic systems of the future.

So Manoharan and his Stanford colleagues brought the problem down into the quantum realm, building tiny nanoscale "quantum drums" out of carbon monoxide molecules on a copper surface. They constructed "walls" only one molecule high and then shaped them into nine-sided enclosures capable of "resonating" like drums. (Apparently this ability is related to particle/wave duality, but specific details about this aspect were hard to come by during my weekend Web surfing.) About 100 carbon monoxide molecules make up the exterior "drums" and inside are around 30 electrons.

And just like macroscale drums, these nanoscale versions of different shapes nevertheless could resonate in the same way. This is called isospectrality. You can see nifty pictures, video, and listen to cool sound samples here, although of course, the sounds have been converted into audible range for humans. In reality, the "sounds" are at frequencies far too high for humans (or even dogs) to hear.

By now, you might be figuring that this just means science failed twice at creating acoustical spectroscopy, both at the classical and quantum levels. And okay, that may be the case. For spectroscopy. But it turns out there is some practical value for being able to build two differently shaped nanostructures that nonetheless have identical properties, particularly as computer chip circuits continue to shrink into the nanoscale. Chip designers would have more than one way to get the same result, giving them extra flexibility, or, as Manoharan phrased it, "Now your design palette is twice as big."

That could turn out to be significant to the design of future quantum computers (assuming quantum computers ever become a reality). Based on their findings, Manoharan's team has also figured out a way to determine the quantum phase of the wave functions of the electrons inside the quantum drums, without directly observing them. The process is called quantum transplantation, and it involves taking measurements from two quantum drums and then mathematically combining that information, thereby enabling scientists to "cheat" the usual limitations of quantum mechanics "and obtain normally obscured quantum-mechanical phase information," according to Manoharan.

Manoharan's work builds on decades of scientific advancement in a wide variety of fields, but one of the most critical is the development of STMs. That's what enables nanoscientists to move around individual molecules on a substrate, for example -- you need a level of precision and control and imaging resolution that just can't be achieved using ordinary microscopy. That's because there are some fundamental physical limits to looking at tiny objects with light, as demonstrated in 1872 by the physicist Ernest Abbe. Basically, you can't see details smaller than the wavelength of the light you're using.

Creating a visual image of an object under a conventional light microscope requires light waves to pass through that object, which are diffracted into what I guess you could call interference patterns. We get our information about the object from those patterns. Ergo, the more diffracted light waves actually reach the instrument's objective lens, the better resolution you get. ("Resolution" describes the distance between two details of an image that can just be distinguished by the viewer. For a conventional microscope using visible light, the best resolution is on the order of 4000 angstroms, and Abbe's calculations limited the magnification factor to 1000 or so.) Diffraction is that thing that happens when light passes through the spaces in an object -- think of how water waves pass through spaces between reeds along the shore of a lake. If a gap is smaller than the wavelength of light, then waves can't pass through the gap. There's no diffraction, and that's bad for resolution.

What was needed was a form of energy with a shorter wavelength of light -- say, an electron. But an electron is a particle! You might say. True, but in 1924, Louis de Broglie proved that not just light, but also electrons -- indeed, all particles -- exhibit the same particle/wave duality. So an electron can also behave like a particle or a wave, which means an electron beam should, in principle, be useful as a means of "seeing" smaller objects than light waves. Enter Swedish physicist Ernst Ruska, the son of a professor of the history of science, who grew up fascinated by his father's instruments, particularly a large microscope. The young Ernst went on to study electrical engineering, and while still a student at Berlin Technical University in the late 1920s, applied de Broglie's equations to the notion of an electron microscope, concluding that it should be able to see smaller objects than light. He also figured out that he a magnetic coil could serve as a "lens" for electrons, and irradiating an object with an electron beam could produce a useful image. In 1933, he built the very first electron microscope, and subsequently helped commercialize the technology, which pretty much revolutionized science. That's why Ruska was honored in 1986 with the Nobel Prize in Physics, at the ripe old age of 80.

Ruska shared the prize with Gerd Binnig and Heinrich Rohrer, co-inventors of the first scanning tunneling microscope while both were employed by IBM's research group in Zurich, Switzerland, in 1981. It's not entirely accurate, scientifically, to call this technique a form of microscopy, since we're not really looking at the sample via light at all anymore. We're feeling the surface with a mechanical probe, much like a blind person reads Braille by touch. An STM is far more sensitive than a fingertip.

It's a pretty basic set-up: you have a stylus with a very sharp tip mounted on a flexible cantilever. As the tip moves across a surface -- without actually touching it, mind you -- there are going to be interaction forces between the tip and the surface, and these are going to affect the cantilever's movement in turn. Those movements can be detected by piezeoelectric sensors, and turned into images. It is the sharpness of the stylus and how well it can traverse the structure of the sample's surface that determines the resulting image resolution.

It should probably be noted right about now that STMs are just one kind of scanning probe imaging technique; there's an entire family of such techniques, including atomic force microscopy (AFM) which measures the interaction force between the tip and the surface. (The STM, in contrast, measures a weak electrical current flowing between the tip and the sample as they are held a very short distance apart.) There's pros and cons for every type of technique, and for the various "modes" in which they operate, which is why the "family" is still growing. But they're all based on the same basic principle.

Ironically, even though it's meant to commemorate the history of the STM, the March Meeting session will focus on some of the latest innovations in research using STMs. For instance, Sergei Sheiko of the University of North Carolina at Chapel Hill will talk about his work using scanning probe microscopy to image flexible polymer molecules whose sizes are beyond the limits of standard optical resolution. He's been able to get very high resolution of the molecular structure of those polymers, and  has used AFM to study them as they move and react on surfaces. Sheiko's work could lead to better control over surface-activated changes in coatings, lubrication, catalysis, and biochemical assays, by revealing how those changes impact molecular structure and properties. And that's just the tip of the iceberg, or the cantilever, in this instance. It's a solid bet that further innovations in STM and related technologies will yield even more insight and unprecedented atomic-level control over the next 25 years.

at play in the ivory tower

Tuesday marked our second "blogiversary" here at the Cocktail Party, and we pretty much missed it, because we were far too busy putting in our first full day as Journalist in Residence at the Kavli Institute of Theoretical Physics in Santa Barbara. It's an utterly gorgeous campus, with picture-perfect weather, prompting Jen-Luc Piquant to wonder how anyone ever gets any physics done whatsoever in such a setting, although the Spousal Unit assures us that yes, indeed, much excellent physics gets done here all the time. I've been excited about coming here for many months, for lots of reasons, not least of which is to finally figure out just what it is that the Spousal Unit does all day as a theoretical physicist. The job description appears to be something like, "Think really hard about big, difficult, questions involving complicated equations and bizarre counter-intuitive notions, then argue about your conclusions with your colleagues." Every now and then, someone writes it all down and publishes a paper summarizing the arguments to date. And everyone argues about that for awhile, more papers get published, and slowly some sort of theoretical consensus emerges.

If my first couple of days are any indication, this pretty much turns out to be the model at work at KITP, except there are cookies and fresh coffee every afternoon in the Common Room. I did not have the most auspicious start, thanks to a nasty bout with the flu over the weekend that hadn't quite worked its way out of my system by the time Tuesday morning rolled around. It's tough to be gregarious when your sinuses are so clogged, you feel like one of those cartoon giant-balloon-heads in the old Sudafed commercials. Nonetheless, I gamely tried to keep pace with that morning's speaker, Christof Wetterich, who had some thoughts about why the cosmological constant goes to zero.

Now, I have a passing familiarity with the history of the cosmological constant, a.k.a., lambda, a.k.a., "Einstein's Biggest Blunder." Quite probably most reasonably scientifically literate people have heard of it, especially since physicists discovered that the expansion of the universe is actually accelerating instead of, say, slowing down. It's one of the reasons the Spousal Unit (among many others) considers this to be a kind of golden age for cosmology -- or at least the equivalent of a "full employment act" for cosmologists. Heck, there was time not so long ago when we didn't even realize the universe was expanding; scientists assumed the cosmos was static and unchanging, and would pretty much run forever.

That was the state of things in 1917 when Albert Einstein put the finishing touches on general relativity. But there was a niggling problem: his calculations indicated that the universe should be expanding. To get the theory to fit in with prevailing scientific consensus, he introduced a mathematical "fudge factor": the cosmological constant. It implied the existence of a repulsive force pervading spacetime that counteracts the gravitational attraction holding the galaxies together. With the "push" and "pull" essentially balanced out, the universe would indeed be static.

Einstein probably should have trusted his mathematical instincts, because 12 years later Edwin Hubble was studying distant galaxies, noticed a pronounced "shift" to the red end of the electromagnetic spectrum, and reasoned that this cosmic Doppler effect could only occur if the light were traveling across space that was still expanding. That's why Einstein denounced lambda as his "greatest blunder." Except maybe it wasn't such a big blunder after all. Our universe still holds a few surprises. In 1998, two separate teams of physicists measured the change in the universe's expansion rate, using distant supernovae as mileposts. And they found that the universe's expansion is actually speeding up, thanks to the repulsive gravity of a mysterious thing called dark energy.

While it's not the only theoretical game in town, lambda is arguably the leading candidate for the dark energy. It's not a perfect explanation (it appears to be way too big, for starters), but quite a lot of very smart people are curious about the peculiar nature of this cosmological constant. I don't know why  it's so critical to figure out why lambda goes to zero; honestly, I was under the impression it kinda fluctuated around zero. Or 1. Basically some tiny amount that is not quite zero, because that's the vacuum energy. Quantum physics holds that even the emptiest vacuum is still teeming with virtual particles that wink in and out of existence in an intricate quantum dance, so even a completely empty universe would still have some residual energy in these quantum fluctuations. 

Wetterich is one of the folks who's been worrying away at the problem for quite some time now, and had some novel (to me, anyway) thoughts on the topic. At the risk of over-simplifying things, there's two basic approaches to the problem of dark energy: one that assumes it is, indeed, constant, i.e., static, and has been set since the birth of our universe, and another type of model ("quintessence") that assumes it is dynamical and changes over time. Most observations to date seem to support a static (or mostly static) dark energy.

Wetterich seems to uncomfortably straddle both schools of thought: namely, his model seems to assume that lambda used to be dynamical, and now it's mostly static. He's noticed an intriguing connection between dark matter density and neutrino properties, i.e., the present dark matter density is given by neutrino mass. As best I could figure out, in early cosmology, neutrino mass wasn't all that important (says Wetterich, per my scribbled notes, who claims it was still "relativistic" back then), but then neutrino mass began to grow, eventually getting so large that it became "non-relativistic," thereby constituting a kind of transitional "trigger event" marking the end of the "matter dominated period" and the beginning of accelerated expansion. And so we get the almost static dark energy that scientists believe permeates the cosmos today.

I think that's the gist of what he said. Things quickly went over my head, technically, with talk of cosmon couplings, (SU)3 symmetries, warped branes, even mention of a solution to Einstein-Maxwell theory in six dimensions, just for giggles. So I cannot say much about the merit of Wetterich's argument, except to say that many of the other physicists present were having none of it, and they weren't at all shy about saying so, which made for a hugely entertaining discussion, from my perspective. Allusions to "quantum fluctuations" got batted about as a major objection -- quantum fluctuations have a lot to answer for, if you ask me -- along with accusations that this was nothing more than a "self-tuning universe" argument in sheep's clothing.

I kept waiting for Wetterich to throw down the proverbial gauntlet and an outright brawl to ensue, perhaps to be resolved with pistols at sunrise the next day (there is a very pretty beach just outside and plenty of other scientists around to serve as seconds). But in the end, physicists are civilized sorts, and kept themselves to verbal fisticuffs. Nobody seems to have taken things personally. By the time cookies were served in the Common Room, everyone was best of friends again. Cookies and caffeine can go a long way to smoothing over ruffled feathers, I guess.

It's not all pitched academic battles over the finer points of modern cosmology, of course. There are forms to be filled out, parking permits to be grappled with, wireless connections to be made, and the handing out of the ceremonial coffee mug. But the heart of the institute is exactly the kinds of scientific exchanges that took place that first Tuesday morning -- maybe the debates aren't all quite as heated, but any decent theory needs to be able to withstand a rigorous pounding now and then. That's how science progresses. So it was kind of nice to be able to have a ringside seat and watch that progress in action -- a privilege I can relish for the next 12 weeks.

free range physics

Many of us take our public libraries for granted. It wasn't always the case. When I was a kid, the highlight of my week was when I'd accompany my mother to the local public library to check out a new selection of books. And when I was an impoverished student and young adult, the local library was the only way I could afford new reading material. But with financial stability came the wherewithal to actually buy books again, and libraries play a far lesser role in my life than in years past. Perhaps that could change, however. I have the good fortune to live just three blocks away from the Central Public Library in downtown Los Angeles: a lovely building with Schroedinger's equation carved into one of the stones gracing the steps outside, so really, how could I not be a fan? But it also has an active outreach program (volunteer tutoring) and regularly hosts taped "conversations" between authors in the Mark Taper Auditorium, free to the public as part of the ALOUD program.

I had the privilege of participating in one such "conversation" last week, hosting an evening with Richard Reeves, who just published A Force of Nature: The Frontier Genius of Ernest B. Rutherford. I was a bit outclassed, frankly: I'm a lowly science writer with a couple of pop culture physics books under my belt, whereas Reeves is former chief political correspondent for the New York Times with a list of honors and awards as long as my arm. His many books include a trilogy on modern American presidents: biographies of Kennedy, Nixon, and Reagan. Some might find it surprising to see Reeves turn his hand, then, to the biography of a venerable physicist, but it's less so if you know something of his background. He came of age during the Sputnik era, and graduated from Stevens Institute of Technology in New Jersey with a degree in mechanical engineering. So Reeves is no stranger to science.

That shows up immediately in his new book, which opens with a fascinating account of a recreation of Rutherford's pivotal scattering experiment in 1908. Reeves managed the feat with the help of a group of modern-day physicists at his alma mater, and I can't think of a better way to start such a book. After all, in a sense, this is well-traveled ground. While hardly a household name today (except in New Zealand, where he practically deified), Rutherford was once as famous as Albert Einstein, with the press reporting breathlessly on his latest research accomplishments. It helped that his research was literally earth-shattering: first he proved that the atom was not indivisible, then he won the race to "split" the atom, against teams with much bigger machinery and funds. Somewhere along the way he also won the Nobel Prize in Chemistry for his work on nuclear half-lives/radioactive decay. (There is more than a little irony in this, since Rutherford is also the person who famously observed, "All science is either physics or stamp collecting.")

Anyway, the scattering experiment is noteworthy because Rutherford noticed, a few years earlier, that a narrow beam of alpha particles became a bit "fuzzy" after passing through a sheet of mica -- a puzzling little anomaly, hardly worth noting, unless one happened to be a great physicist. "Rutherford was a great one for mulling over aberrations, anything out of the ordinary," Reeves writes. "That is where the secrets were, in the margins." So like all great scientists, Rutherford persisted. He set his assistant, Hans Geiger (inventor of the Geiger counter), the task of measuring the relative numbers of alpha particles according to scattering angle, and an undergraduate student, Ernest Marsden, got the thankless task of analyzing all the data to see if any alpha particles were reflected from metals. The answer turned out to be yes: in fact, some alpha rays were  scattered directly backwards from a thin film of gold, almost, said Rutherford, as if one had fired a large naval shell at a piece of tissue paper and it had bounced back. The only explanation of this result is that almost the entire mass of the atom is concentrated into a nucleus a thousand times smaller than the atom itself.

Fast forward not quite 100 years later, to November 5, 2005, when Reeves found himself  in a darkened laboratory in New Jersey, trying to get his eyes to adjust to the darkness so that when he looked through a microscope into the vacuum chamber he and his cohorts had constructed, he would see the telltale "scintillations": sparks of light, the result of alpha rays striking a phosphorescent wall after passing through a bit of gold foil.

It wasn't easy recreating the experiment. While vacuum technology had come a long way since Rutherford's time, it was also quite a bit more difficult to get hold of radioactive materials. Rutherford thought nothing of tossing bits of radium into his coat pocket, or depositing them into his desk drawer. (Apparently it cost $100,000 to decontaminate the famed physicist's desk before it was deemed safe for display. Yet Rutherford never showed any signs of radiation sickness in his lifetime.) Reeves' team had to use a distant descendant of radium, Americium-241, a significantly weaker source. Compare: the radon-222 used by Rutherford in his 1908  experiment produced 30 billion alpha particles per second, while the amercium-241 used by Reeves' team produced around 370 million particles per second. But they succeeded! Maybe they didn't recreate the experiment 100%, but they managed a solid 90%.

Based on the portrait that emerges in A Force of Nature, I suspect Rutherford would have approved of Reeves' willingness to roll up his sleeves and get his hands dirty with the real work of physics: cutting, sawing, soldering, and so forth. What I liked most about Reeves' biography is how it brought Rutherford the man to light: not just the scientist. He was quite the character, frankly. One of 12 children born to a New Zealand wheelwright/engineer (and later flax miller) and his schoolteacher wife, Rutherford showed early academic promise and eventually won a grant to study at the famed Cavendish Laboratory at Cambridge University in England. The lab's head, J.J. Thomson, took the promising young New Zealander under his wing and directed him away from his early research into radio waves and wireless transmission, into the nascent field of atomic physics.

It meant diverting the young man away from a path that would have made him extremely wealthy; Guglielmo Marconi eventually won the wireless race, and died a very rich man.  But Rutherford was an idealist at heart, and he followed his curiosity to investigate the nature of the most fundamental building blocks of nature instead: the structure of the atom. His scattering experiment proved once and for all that the atomic nucleus was not indivisible, and his model of the atom -- a tiny nucleus made of positively charged protons and neutral neutrons, around which orbited negatively charged electrons -- quickly supplanted Thomson's working "plum pudding" model. (You can build your own atom here.)

Rutherford was the last of the great "tabletop" experimentalists. Nowadays we have massive accelerators to smash particles into even tinier bits and pieces, at ever higher energies, but many of Rutherford's apparatus were no bigger than the proverbial bread box, and used such mundane items as string and sealing wax. All those years roughing it on New Zealand farms made Rutherford both thrifty and creative when it came to experimental materials. Reeves relates one anecdote of a young scientist under Rutherford who needed a bit of metal tube for an experiment; Rutherford had the young man saw off a piece of the handlebar of an old bike in the lab he'd kept around just in case the parts were needed.

Rutherford's early years at Cambridge were marred a bit by the snobbish elitism of some of his colleagues. After all, he was the first graduate student there who did not actually attend Cambridge as an undergraduate. He was also a bit rough around the edges: big, loud, boisterous, with a strong New Zealand accent. He was often mistaken for an Australian farmer, rather than one of the world's most prominent scientific minds. But he proved his mettle, again and again, and he judged people on their merits in turn. That included women and minorities: he admired and respected Marie Curie, for instance, and while he expressed surprise upon meeting Lise Meitner and finding she was a woman, the fact of her gender did not diminish her scientific achievements in his eyes. Nor was Rutherford especially political. Alas, he had the misfortune to live through the onset of two world wars, losing more than one promising young scientist to the trenches. With the ascension of Hitler and the ousting of Jewish scientists in the 1930s, Rutherford pulled every string he could manage to find places for his former Jewish colleagues. So he was simultaneously a man of his era, and rather enlightened for that day. Some 13 of his former students went on to win Nobel Prizes of their own, so he left an indelible mark on physics beyond the narrow confines of his own research.

One of the more surprising aspects of Reeves' biography is the figure of Rutherford's wife, Mary, a strict religious woman with a sharp tongue who did not hesitate to cut her husband down to size; nor did she mellow with age. She seems to have been the antithesis of her boisterous, gregarious husband. The couple had one daughter, Eileen, who died giving birth to her fourth child. Reeves is not the first to speculate that Rutherford's fond, paternal attitude towards the "boys" in his lab might be indicative of his longing for the son he never had. Lady Rutherford also managed to squelch many of the details surrounding Rutherford's death in 1937 for many years. Rutherford fell while trimming a tree in the yard, and apparently she tried a homeopathic "healing touch" attempt at a cure before calling in a doctor -- at which point it was too late. The great man succumbed to the ignominy of a partially strangulated umbilical hernia, and was buried in Westminster Abbey. His estate: around 7000 pounds, pretty much the amount he'd received for his Nobel Prize. But his place in physics history is rich, indeed.

There's a lot more color and detailed anecdotes in the actual book, which I encourage folks to read on their own. As we were winding things up after last week's conversation, Reeves expressed his surprise and gratitude at the number of people willing to trek to downtown LA on a weeknight to hear about a not-so-well-known (in this country) physicist. I was surprised, too, although I suspect many of the folks who came were there because of Reeves himself -- a writer of no small stature. My favorite moment of the evening occurred when someone asked him if there were similarities between his past presidential biographies and this most recent scientific one. While conceding that Rutherford shared a larger-than-life persona and gift for inspiring others with Presidents Kennedy and Reagan, Reeves said bluntly, "Presidents are pygmies" in comparison to the great men of science -- not meant in any way to disparage the achievements of political leaders, mind you, merely to put those things in true perspective.