My Life as a Quant by Emanuel Derman Page A

into something more formulaic, a set of rules anyone can follow, rules that no longer require the original insight itself. In this way, one person’s breakthrough becomes everybody’s possession.
    After several months I completed the calculations for electrons scattering off quarks. But in the real world electrons scatter off protons—that is, bags of quarks. My next task was therefore to calculate what happened when an electron hit a bag. I embarked on extensive numerical computations using old-fashioned, punched card programs that I submitted to the university computer center to run overnight on their IBM mainframe. It was tedious: In those days we had no interactive terminals or PCs; one typographical mistake in punching the cards could lose you a full day’s work.
    It was then that I learned never to trust any new formula I had derived without thoroughly cross-checking it for consistency from all angles. Usually, anything new and complex is an extension of some older, simpler, and more familiar calculation. The first check is therefore to switch off the complexity and verify that you obtain the familiar results. I found it so easy to make mistakes in my calculations that I began to wonder about the safety of flying—how could engineers possibly trust their calculations when they designed airplanes, where life and death rather than theories and reputations were at stake?
    It took me seven years in graduate school to get my PhD, an astonishing ten percent of a lifetime. There were three preparatory years of coursework, one subsequent warm-up year in the area of my research, and two more years of my actual thesis research. Finally, I spent a half-year writing the thesis, composing a paper for publication, and preparing for my thesis defense. A small number of my friends got out of Columbia in five years, but many took eight or nine.
    Sometimes we tried to save others from our fate. In the early 1970s Doug Hofstadter came by our office in Pupin. He was still unknown, a PhD student in physics at Eugene, Oregon, and not yet the famous author of Gödel, Escher, Bach . It took some time before I realized that he was the son of my cousin’s friend Robert Hofstadter of electron-proton scattering fame. Doug was contemplating a switch to Columbia from the University of Oregon where he was in graduate school. Though it felt deliciously like biting the hand that fed us, we tried to warn him away from Pupin.
    Most of us grew to hate our stay in the physics department. We spent the better part of our twenties shuttered there. For the most part we were ignored, receiving little attention from the people to whom we were apprenticed. My friend Chang-Li Yiu spent more than six months working on a thesis problem without conversing with his advisor, only to discover that his advisor had solved the same problem a few months earlier. Then he had to begin again. Though I was better off—Norman Christ was responsible and I met with him weekly—I often thought I might never complete my degree. You could coast from year to year, receiving your Department of Energy research grant, while no one seemed to care when or whether you finished, or what you would do afterwards.
    In defiance, I struggled to look unbeaten during the final few years. I remember walking hand-in-hand with my wife down Broadway and passing a crowd of Columbia professors strolling up Broadway on the way back from lunch at the Moon Palace. As our paths crossed, I tried hard to look nonchalantly happy and carefree, talking animatedly, pretending to myself and to the professors passing by that they had no effect on the other parts of my life.
    But of course they did. One summer in the early seventies, during the student protests against the American invasion of Cambodia, Eva and I went camping in the Catskills mountains with Chang-Li and his wife. After several days in a tent, cut off from any news, we went to meet my in-laws who were vacationing in a