Nobel Prize Lesson: Distinguish the Improbable from the Impossible
October 5, 2011
Saul Perlmutter was woken at 3 am yesterday by a reporter asking how he felt about winning the Nobel Prize. Any confusion was cleared up a few minutes later when the Nobel Committee in Sweden called. Perlmutter, an astrophysicist who holds a joint appointment at Berkeley Lab and UC Berkeley, and his colleagues Brian Schmidt and Adam Reiss received the 2011 Nobel Prize in Physics for their work in the 1990s in using supernovae to measure the accelerating expansion of the universe. They found, independently, improbable evidence that the universe was expanding at ever faster speeds.
In the process they uncovered other mysteries. The universe is made up of only about 5 percent visible (or baryonic) matter. The remaining 25 percent of the universe is dark matter, and 75 percent of the universe is made up of dark energy. Perlmutter described dark energy as making space more bouncy and elastic. It appears as “a negative pressure—we see it in the equations.” Nobody is certain of the relationship between dark matter and dark energy; scientists are looking for a theoretical concept that will solve them both at the same time.
In yesterday’s press conference at Berkeley Lab, Perlmutter said that the award “recognizes what it is possible to do when whole communities of science come together.” He went on to say, “when you are driven to learn things about the world, you find yourself inventing new things.”
Of course, that is what ESnet is all about—the ESnet network links scientists so they can efficiently exchange data, collaborate, and discover new things about the world. ESnet’s Bill Johnston recalls the early days of data transfer. “Saul started out doing observations at Chabot and Hamilton. He wrote the images on Tektronix cartridge tape and ferried them around in his car. When his tape reader at LBL broke, we would help him out. In the graphics lab that Harvard Holmes and I ran, we had several Tek tape readers. That must have been [the] late 1970s.”
And then there’s Daniel Schectman, a hard-core materials scientist at the Technion-Israel’s Institute of Technology, who today was awarded the Nobel Prize in Chemistry for discovering a new state of matter called quasi-crystals, where atoms make a structured pattern that never repeats. While on sabbatical at NIST in 1982, Schectman was working at the electron microscope, imaging a sample of aluminum and maganese. He made a measurement that seemed to be a mistake– the symmetry of its five-fold crystal structure violated the laws of physics. It is possible to get an identical pattern from structures with 3,4,6 and 8 sides, just like square floor tiles can be repeated in an identical pattern, no matter how you rotate them. But Schectman knew it was theoretically impossible to tile a space in five-fold rotational symmetry.
A former student who took his class in electron beam crystallography at the Technion recalls that Schectman showed the class the research notebook that he kept at NIST. Beside the measurement of the anomalous sample, Schectman scribbled in Hebrew, “there is no creature like that.” Schectman persisted through years of caustic opposition from his peers (Linus Pauling, a two time Nobel-winner, was particularly hostile), to verify his results—he was even asked to leave his research group. The original paper he attempted to publish in the Journal of Applied Physics in 1984 was immediately rejected, but he later published another paper with collaborators that rocked the field of crystallography.
It turns out that to tile a space and achieve five-fold symmetry uses not a single tile, but two—one distorted, a concept called Penrose tiling. But at the time, Schectman was unfamiliar with Roger Penrose’s work; it was an idea that only pure mathematicians played with–it wasn’t even applied mathematics. On an atomic level, quasi-crystals resemble aperiodic mosaics, such as those found in the medieval Islamic mosaics of the Alhambra Palace in Spain and the Darb-i Imam Shrine in Iran.
Schectman’s discovery caused a paradigm shift in chemistry, the Swedish Academy of Sciences said. But exotic quasi-crystals, since they don’t scratch easily, are now appearing in our everyday lives in the non-stick coatings on razor blades, drill-bits, and pots and pans.
Schectman and Perlmutter both stood on the shoulders of people who came before them, and relied on their communities to test and verify their results. The pace of scope of modern day science is making international collaboration not a luxury, but a necessity. Although individual persistence and courage drive many new discoveries, they still take place in the context of a global community of scientists. ESnet and other research and education networks make this community possible, by allowing scientists to share datasets and knowledge and to work together towards even greater discoveries.
“Science is a method, not a finished project; we don’t know where it will lead in the future,” Perlmutter summed up. And networks are forging the way.