Faces of Penn State: James Anderson

James Anderson’s life is full of predictions, from quantum chemistry to his wife's culinary creations. Perhaps that is why he finds scuba diving, a totally unpredictable sport, so appealing.

On the door of James Anderson’s office, you’ll find no name plate, just a large illustration of a mathematical methodology called Direct Simulation Monte Carlo. Tacked to a nearby bulletin board, a tiny tag that looks like it came from the back of a soda bottle: “Sorry, you are not an instant winner.”

The self-effacing Anderson pioneered the application of the Monte Carlo method to the calculation of the energies of atomic interactions. His work has helped him come part of the way toward a life-long goal: solving one of mathematics’ Grand Challenges—the sign problem.

“We can solve very small problems exactly—which is something new and different in quantum mechanics—but that Grand-Challenge problem is still out there for large systems,” he explains.

Anderson, an Evan Pugh Professor of Chemistry and Physics, brings complex information home to his students the old-fashioned way: visual aids. He proudly shows off his notebook of class notes, complete with color transparencies of drunken sailors (the Random Walk), error bars reduced to nothing but a + sign, but magnified to fill the page (“you still can’t see the error”), and the old Johnny Mercer lyrics, “You’ve got to accentuate the positive, eliminate the negative” (the sign problem).

Anderson also finds time to direct the Penn State Consortium for Education in Many-Body Applications supported by the National Science Foundation’s Integrated Graduate Education and Research Training (IGERT) program. Its goal is to expand and improve the work of graduate students and faculty across multiple disciplines.

“It’s interesting the things you have to do to force people to get together!” he says, laughing. “What the NSF is looking for is trendsetters with ideas that will spread—and this could spread.”

Anderson’s latest prediction is that a detonation can go much faster than prev-iously thought (see pg 13). Thanks to faster computers combined with the Monte Carlo method, Anderson was able to predict some-thing never before imagined to be true. “Simplified models, in which the shock wave is assumed to precede the reaction, are incomplete,” Anderson writes in his paper on the discovery. “We find that the reaction and the shock regions may overlap and ‘ultrafast’ detonations may occur.” While he down-plays the effect of this discovery, he admits that it could affect how scientists respond to some observations they have been making.

Anderson’s life is full of predictions. That may be why he enjoys scuba diving, a totally unpredictable sport he jumped into only five years ago. He now travels to Grand Cayman or Bonaire for some of the best diving in the world.

But his mind is always working on the sign problem somehow. “The beauty of working on that particular problem is that you could hit it at any time. The solution could be just around the corner.”

--Suzan Erem