Power of analogies in science

If you know how a basketball spins on each of its axes, then it turns out that you also know how a classical methane molecule spins. Such analogical pairings are useful because they allow you to better understand the less familiar of the pair through what you know of the other. The trouble, of course, is that analogies are often imperfect. Not every property is directly connected between the pair. So you have to be careful to assign which are mappable. For example, you certainly won't be able to play basketball with methane despite the analogy with respect to rotations.

Meanwhile, mapping a problem to one that is even more difficult to solve sounds like a bad idea. But if the more difficult problem solves itself them you just might win out after all. Toshiyuki Nakagaki and his colleagues at Hokkaido University did just this, twice. First, they showed that they could map simple mazes onto a board in which mold could grow. It turns out that after a while, the mold grows best along the shortest path between the ends. It would be very difficult to simulate the mold growth, and yet the analogy allows the mold to solve a complicated optimization problem for us. It turns out that you can replace the maze with a real problem related to finding the best possible train network connecting some number of cities over a selected terrain. Now the mold can be used to find the optimal rail network. For each of these two analogies, Toshiyuki Nakagakii received ig Nobel awards. I mention him, in particular, because I got a chance to meet him while I was in Japan. And now, I wonder if I might be able to map the solution of a chemical reaction pathway to his mold growths?!

In detail, the dates and prizes of the teams recognized by ig Nobels for mold growths mentioned above are:

2008 ig nobel in Cognitive science: Toshiyuki Nakagaki, Hiroyasu Yamada, Ryo Kobayashi, Atsushi Tero, Akio Ishiguro, and Ágota Tóth, for discovering that slime molds can solve puzzles.

2010 ig nobel in Transportation Planning: Toshiyuki Nakagaki, Atsushi Tero, Seiji Takagi, Tetsu Saigusa, Kentaro Ito, Kenji Yumiki, Ryo Kobayashi of Japan, and Dan Bebber, Mark Fricker of the UK, for using slime mold to determine the optimal routes for railroad tracks.

Ramen got game

While in Japan, I was initially shocked to see the popularity of ramen noodle shops. I remember ramen as the dried stuff (in a bag or cardboard box) that you add water to for a quick but very salty meal. Adding further to my surprise, I subsequently ran into this month's article in Delta magazine on ramen noodles! Apparently, ramen has all grown up and its the latest trend. In New York, you can have a bowl at Momofuku if you are able to brave the wait. I haven't been to Tokyo to confirm the article's claim that Ramen was formed in the early 1900's out of a fusion of Japanese and Chinese cuisines. However, I believe my hosts in Sapporo who exclaimed that ramen was truly invented in Hokkaido. Regardless, there is no question that the ramen dishes available in different parts of Japan are different, and all are very good!

In addition to resonating with the idea of interdisciplinarity, ramen offers another metaphor to chemistry. The recipe is a basic protocol but a given dish is as interesting as your imagination. You choose a solvent, add porous solids with lots of surface area, and complete it with other solids to change the overall color and nutrient composition. From that basic recipe, you can make countless combinations. At the simplest level, chemists just put chemicals together (following an appropriate protocol) to make still other chemicals. The genius of it lies in knowing what's going to come out (and how to extract it) so that it can be of use. And that's just like the premier ramen chef who knows just which combination of items will make tasty ramen.

Emergence and Campai

I was asked to make the final remarks at the end of the banquet of the recent 14th RIES-Hokudai Symposium.* Quite an honor, but also a lot of pressure. One thing I've learned over the years is that humor rarely translates, and it's easy to accidentally offend in a foreign language. My only saving grace was that the expectations were low. The symposium theme is "mou" —meaning networks— and that presumably had to be weaved in too.  So what to say?

I started by saying "Minasan Konichiwa." That got a round of applause. Proof that the expectations really were low. But here's the kicker: I asked Professors Tsuda, Nakagaki and Ohta, in turn, to say "campai." Each did so but at a sound level that was barely audible. I then asked all three to say "campai." The volume of sound was not the sum of the three earlier statements which would have remained barely audible. Rather, it was loud enough for all to hear easily. This little experiment involving a social network with sound as the observable is indicative of a non-additive (nonlinear) emergent phenomenon. I did not tell my three participants that I planned to ask them to do this. So I really got lucky that the experiment worked as planned. In so doing, though, I was able to provide an example of emergent function arising from collective (network) behavior in a way that most of the audience was able to appreciate and toast to. It also served as a basis for the seminar I delivered the following day on the emergence of structure from Janus and striped particles. Campai!

*Check out my recent post on the 14th RIES-Hokudai Symposium here. RIES is the Research Institute for Electronic Science at Hokkaido University.

The chemistry within networks

On December 11 and 12, my friend, Tamiki Komatsuzaki, organized the 14th RIES-Hokudai Symposium in Sapporo, Japan. I was lucky to be invited to present our work. I would argue that all the speakers were similarly lucky. The symposium was a gathering of representatives from disparate fields and several countries. While there, I learned that "Hokudai" itself is a fusion of Hokkaido and Daigatsu (university in Japanese).

At the RIES-Hodukai Symposium, we were brought together under the unifying theme of networks (mou in Japanese.) Network theory is fast growing into its own independent field, but it also serves as an interdisplinary glue connecting mathematics and computing to nearly everything. As such, the speakers spoke about transportation, nanoparticles, organic synthesis, cells, et cetera. The theme is also a double entendre. One intent of the workshop is to create a stronger human network between its diverse participants. This resonates with Prof. Kohei Tamo, the current President of the Chemical Society of Japan: “I often advise young researchers to make 100 friends at the expense of one paper." Of course, the network doesn't help if you don't have the papers (and the results they represent.)

It was exciting to see and participate in this effort urging us all to think about science broadly and across international lines. Hats off to Japan for supporting this!

2. What's in a name? At the crossroads between chemistry and physics

In the 1700's, a dramatic paradigm shift was brewing in the chemical sciences. Until then, chemistry had been part art and part taxonomy. The question was whether one could make sense of it all based on fundamental principles about the substances themselves. (We didn't quite yet know that substances were made of tiny building blocks, namely atoms.) Or to put it bluntly, is there an underlying physics to chemistry? Thus physical chemistry (or is it chemical physics?) was born as an interdisciplinary science. It's now a part of the core of the discipline of chemistry. It is also a popular node in the web science in which the interdisciplinary sciences act as the links.

The interdisciplinary field lying between chemistry and physics took hold in the late 19th century. Ostwald recognized the power of the new physics of the day—thermodynamics—to help make sense of the energetics or molecular motions and reactions. Thus was born the field of physical chemistry, and the eponymous journal within the American Chemical Society. The trouble is that when new physics—such as quantum mechanics—came along, the editor of the Journal of Physical Chemistry at the time wasn't ready to accept it. This led to the rather odd definition of physical chemistry as being limited to the thermodynamics of chemical processes. This, in turn, necessitated the definition of a new interdisciplinary field, chemical physics, which included the use of all physics (even thermodynamics) to understand chemical processes. As the corresponding eponymous journal was subsumed under the umbrella of the American Institute of Physics, some chemists (though not most) did not make the jump to chemical physics. This, in turn, led the Journal of Physical Chemistry to focus on topics in the middle of the 20th century with decreasing relevance. (Fortunately this misdirection did not persist, and the happy ending is coming soon!) Meanwhile, the name confusion continues to recur as students routinely ask me what exactly is the difference between chemical physics and physical chemistry today. My answer to the question follows in the posts to come!

(Note that this is the second post in a series. Click here for the previous post.)

1. Interdisciplinarity is a buzzword in science, but how modern is it?

Everywhere you look, it seems that we are talking about new paradigms in science. Among the various disruptive forces, "interdisciplinarity" (or perhaps we should call it multidisciplinarity?) appears to be ever present. It certainly seems modern to be thinking about the breaking down of disciplines. Presumably, our students must learn new tools from each of the disciplines and thereby advance science in ways that the current dogma cannot. But would you be surprised if I were to bring up such a movement from the 1800's? How modern would that be?! Or perhaps, the current movements are actually post-modern in the sense that interdisciplinary sciences are a return to the beginning when science was but a single unified whole?

In the (post)modern science at the turn of the 21st century, the fundamental problems confronting us appear to require a new breed of scientist: interdisciplinary scientists who act as connectors between distant fields. Examples include so-called energy scientists, environmental scientists and data scientists. It has also driven the construction of institutes or buildings, such as the Molecular Sciences and Engineering Building where I work at Georgia Tech, that collocates students and practitioners in order to advance interdisciplinary research. The story of the development of physical chemistry coined around 1752 by Mikhail Lomonosov and taking root in the late 19th century doesn't diminish the value of these recent interdisciplinary threads in science. Rather, it is but one of the many examples in which the development of ties between existing disciplines—chemistry and physics in the case of physical chemistry—has led to major advances in the sciences. Thus interdisciplinary sciences are not a modern fad. History tells us that their growth has been a critical part of the practice of advancing science all along. In a short series of posts, I plan to summarize how the development of this emergent field had dramatic impacts on the practice of its science.

Collaboration in Art and Science

This past weekend, I visited the Dalí exhibition at the Museum of the Reina Sofía in Madrid. Dalí was much more prolific than I had realized (thus my walk through the galleries took twice as long as I had anticipated) and he was a (very disturbed) genius. But the real surprise was how much his trajectory had crossed other great artists in his and in distant fields. For example, he worked with Hitchcock on Spellbound. He worked with Luis Buñuel on a number of his movies, and with Disney on a pair of animated shorts. He is also well known for his ups and downs with his fellow surrealists and his willingness to monetize his craft through so-called Avida Dollars. It's amazing that art which appears to be so individualized is evidently quite collaborative.

In similar fashion, the progress of science is extremely collaborative. One often thinks of the great physicists acting alone while laying down the foundation for quantum mechanics, but it was the Copenhagen interpretation (born from collaboration) and presented at Solvay in 1927 that truly cemented the foundation. In today's world, scientists, great and small, necessarily collaborate. That's why I'm here in Madrid in the first place. I'm working with complex dynamicists at the Politéchnica, a mathematical chemist at the Autónoma, and a mathematical physicist at Loughborough. Together, we're trying to make sense of the structure of the multi-dimensional surface that separates reactants from products. It turns out that this is, by now, fairly well understood when the number of atoms can be counted on one hand regardless of how many fingers you actually have. The trouble is that when you put molecules in a liquid (or some other complex media), it's a bit more difficult to keep track of all of them. So that's where working in a group of people with different talents and expertise comes in useful. And, like Dalí, we need to eat, so we'll take any dollars (or euros) that will allow us to advance our science!