Employed scienceRoslyn | March 23, 2011
It’s when applied science gives back, contributing a piece to the basic research puzzle.
Jaded grad students like me get a warm fuzzy feeling when we hear about people reaping unexpected benefits – economic or social – from the results of pure science. Last night I was reminded that this can work in the opposite direction.
Matthew Mecklenburg and Chris Regan, two physicists from UCLA with interests in quantum theory and its applications for sustainable energy, wanted to design a better transistor. Instead, they discovered something fundamental about the structure of the universe1. Hidden from our eyes and our finest instruments, the space that surrounds us might be more like a chessboard than a continuous expanse.
Mecklenburg, a grad student, was investigating graphene as a potential material to make more efficient transistors – the little bits of silicon that allow computers and essentially all modern electronic devices to function. He needed some precise measurements of the way light interacts with graphene at the nanoscale, to assess feasibility of the new design. These experiments gave Mecklenburg a quantitative picture of the way electrons hop around in the lattice of carbon atoms in graphene. And that’s when the chessboard struck.
Mecklenburg and Regan realized that the hopping behaviour of electrons in graphene was formally equivalent to what happens when an electron flips its “spin” – a theoretical concept that has remained an enigma since it was described in the early 20th century.
The trouble is that “spin” implies that electrons have angular momentum, but the electron itself is not supposed to take up any space. It is truly a point particle. And if it does have dimensions and a surface, the motion of “spin” would have to be faster than the speed of light – a physical impossibility. Mecklenburg and Regan’s investigation of graphene suggested that “spin” can derive from spatial structure, rather than angular momentum, if physical space is analogous to the honeycomb of atoms in the graphene crystal lattice. In other words, if you get down to a very small scale, the units of space become indivisible – like discrete steps on a chessboard – and the phrase “in between” loses all meaning.
In their paper, Mecklenburg and Regan derive the equations that demonstrate how this new perspective can resolve the electron spin conundrum. Their results also explain some formerly puzzling aspects of the way graphene and carbon nanotubules interact with light1.
This reminded me of another example (and I’m sure there are more). In 1964, Arno Penzias and Robert Wilson were engineering a new type of microwave “horn” antenna at Bell Labs, for applications in communications and astronomy. But they kept getting some perplexing noise in their data. One by one, they eliminated potential sources, right down to the pigeons nesting in the vicinity. According to this article, neither Penzias nor Wilson will admit to being the one who ordered the pigeons to be shot, but Penzias famously described cleaning all of the poop out of the antenna as a last resort.
The white stuff wasn’t the source of the noise, though; the big bang was the real culprit. Penzias and Wilson’s new antenna was getting a read on the cosmic microwave background, the thermal energy left over from the birth of the universe. It had been predicted nearly 20 years earlier by theoretical physicists including George Gamow. Now, for the first time, there was a device sensitive enough to detect it. Penzias and Wilson’s discovery was the final nail in the coffin for alternatives to the big bang theory, and they were awarded the Nobel Prize in 1978.
Don’t get me wrong: I love trotting out the latest argument in favour of pure, curiosity-driven science as much as the next academic. Politically, I’d be hard pressed to agree with an increase to applied funding if it came at a cost to basic research. In fact, I firmly believe that in the long run, most economic growth comes from basic science. Here’s a back-of-the-napkin proof. The Scottish physicist James Clerk Maxwell discovered the connection between electricity and magnetism in the 1860s. His eponymous set of equations, published 150 years ago this month, are the foundation for our use of electromagnetism and light in technology. This includes all modern communications devices. According to quantum physicist Stig Stenholm, Maxwell’s discovery alone has “paid for all fundamental research for the following 500 years.” 2
We can’t live without pure science. But the stories of applied researchers making revolutionary discoveries resonate, too. And for me, it’s not the politics. It’s the faith.
The enterprise of science can be unpredictable. Senior researchers might be able to predict where the good stuff will come from next, but this is not the case for truly revolutionary, paradigm shifting discoveries. Even the traditional model of basic research fueling innovation in a simple linear path is a major oversimplification, as Simon Schaffer argues in a commentary on the history of Maxwell’s equations3.
Unfortunately, the one thing we can count on is that most research yields will be pretty mediocre. Students know that most of the bench work we drag ourselves through, day after day, won’t pan out as well as we’d like. We need hope, and a good measure of irrationality, to get through it.
That hope can come from two sources. First, the fact that failure can lead to knowledge, like when unexpected noise reveals some new truth about the universe. Second, as the chessboard example shows, you never know when you’re going to strike gold (or be down the hall from someone who does), no matter your field.