News & EventsJournalist Turned Physicist

This summer, Campus Buzz writer Marjan Hajibandeh ‘09E will sit down with each of the seven Amherst professors who’ve just earned tenure. First up: Jonathan Friedman, associate professor of physics.

There’s no way around it; Jonathan Friedman looks exactly like what I imagined a physicist to look like. He has tousled curly hair and wire-rimmed glasses. When (in an early draft of this article) I described them to be circular, he corrected me and said that they were more stadium-shaped. If he were any more empirical, I would have guessed that he lived in the lab. And, boy, was he eager to chat about his research. But I wouldn’t let him—at least not right away.“Weren’t you a journalist at one point?” I inquired, noticing he asked more questions than he answered.

He confirmed my suspicions and even commented that he used to carry a notepad like the one I was busy scribbling on.

All of a sudden I wished I’d brought a tape recorder.

Luckily, that’s when the stories started to pour out. Though Friedman loved physics and majored in it while at Vassar College, his hobby began to take over his life. He was an editor of one of his college newspapers and thrived on the “immediate feedback” he received from his stories. After college he spent time editing a newsletter for a national supercomputer center before landing his first “real” reporting job writing for a weekly newspaper in central New Jersey.
While there, he helped oust a police chief for embezzlement and even got a mayor to pull out of a re-election campaign. This was sounding like a dream job to me, but Friedman burst my bubble with his next comment.

“It was enjoyable because I felt like my job had relevance,” he said, “but at the same time, we were grossly underpaid. We were paid for 40 hours a week but obviously worked much more than that. And it was a lot of grunt work, much of which I didn’t care about.”

I hoped he didn’t assume that I thought of our interview that way. I was actually having a lot of fun. “So what finally made you want to leave?” I asked.

“I think I write well,” he elaborated, “but I was never really efficient at it. Especially compared to some of the other guys I was working with.” When you have to write 10 stories a week, the prose often gets formulaic, he explained.

After realizing that the life of a journalist was not for him, Friedman tried to find a teaching position. But with no license or credentials, he couldn’t land a job. About that time, a visit to a friend in Chicago planted the idea that he could get some teaching experience by becoming a graduate teaching assistant. Two weeks before the semester started, Friedman applied for a teaching assistantship at the City University of New York, where he stayed to get his Ph.D.

Now that I felt he’d earned it, I let him tell me about his research.  

Even if you don’t have a background in physics, you need only be familiar with Schrödinger’s cat to appreciate the quantum measurement problem, the physics that underlies Friedman’s research. Say you’ve got a cat trapped in a box, and also in that box are a flask of poison and some Rube-Goldberg apparatus that can be triggered to break the flask when a radioactive decay is detected. A small amount of radioactive material is placed in the box and after some time there is a certain probability that a nucleus will decay and, thus, release the poison. However, until you open that box, you do not know the fate of the cat; thus, the cat is in a “superposition” of both “alive” and “dead.” If the laws of quantum mechanics are taken literally, this superposition exists until you make a direct observation.

“If you open the box,” Friedman explained, “and find the cat dead, did you kill the cat?”

And, thus, we reopened the same conundrum that has plagued physicists since Schrödinger's 1935 thought experiment: why do quantum properties break down at the classical level? Some of Friedman’s research involves a slightly different animal: a SQUID (Superconducting Quantum Interference Device), which essentially functions at an energy scale between the microscopic and macroscopic. In these superconducting rings, electrons condense to form a single entity – a macroscopic quantum object. According to classical laws, the current should flow in a single direction, clockwise or counterclockwise. Nevertheless, Friedman’s research in 2000 demonstrated a macroscopic superposition, where the current flowed in both directions simultaneously.

To get a sense of what’s going on, imagine  a big curvy “W”—two wells separated by a barrier—with a small ball sitting in one of the wells. For fun, we’ll call one well “clockwise” and the other “counterclockwise.” The ball is compelled to stay in its well unless some burst of energy bumps it over the barrier and into the other well. In the SQUID, however, the current is able to “tunnel” from one well to the other to create a superposition of both directions.

The research has potential applications to the burgeoning field of quantum computing. Think of binary code in which information is processed in series of 0s and 1s. Quantum computing takes advantage of superposition states to do “quantum parallel processing.”  If the input to your computer is not one number, but instead the superposition of, say, two different numbers, then the output will be the superposition of  two different outputs; the computer essentially does twice as much processing in the same amount of time as a classical computer. For certain problems, it turns out that quantum computing is more efficient than classical computing. Quantum algorithms are much more effective than their classical counterparts in decrypting some codes, including the ones that secure our Internet transactions. And a quantum algorithm can significantly speed up search processes, like those we do daily on the Web.

I thought of Google and my bank account, and I decided that, while it isn’t quite like exposing crooks in office, Friedman’s work is actually quite relevant to my life. Maybe physics isn’t so different from journalism after all.