In the end, I graduated summa cum laude, Phi Beta Kappa, with honors in the major, having excelled in the department’s three-term sequence in quantum mechanics and a graduate course in gravitational physics, all while teaching myself to program Yale’s mainframe computer. But I didn’t go into physics as a career. At the end of four years, I was exhausted by all the lonely hours I spent catching up to my classmates, hiding my insecurities, struggling to do my problem sets while the boys worked in teams to finish theirs. I was tired of dressing one way to be taken seriously as a scientist while dressing another to feel feminine. And while some of the men I wanted to date weren’t put off by my major, many of them were.

Mostly, though, I didn’t go on in physics because not a single professor — not even the adviser who supervised my senior thesis — encouraged me to go to graduate school. Certain this meant I wasn’t talented enough to succeed in physics, I left the rough draft of my senior thesis outside my adviser’s door and slunk away in shame. Pained by the dream I had failed to achieve, I locked my textbooks, lab reports and problem sets in my father’s army footlocker and turned my back on physics and math forever.

Not until 2005, when Lawrence Summers, then president of Harvard, wondered aloud at a lunchtime talk why more women don’t end up holding tenured positions in the hard sciences, did I feel compelled to reopen that footlocker. I have known Summers since my teens, when he judged my high-school debate team, and he has always struck me as an admirer of smart women. When he suggested — among several other pertinent reasons — that innate disparities in scientific and mathematical aptitude at the very highest end of the spectrum might account for the paucity of tenured female faculty, I got the sense that he had asked the question because he genuinely cared about the answer. I was taken aback by his suggestion that the problem might have something to do with biological inequalities between the sexes, but as I read the heated responses to his comments, I realized that even I wasn’t sure why so many women were still giving up on physics and math before completing advanced degrees. I decided to look up my former classmates and professors, review the research on women’s performance in STEM fields and return to Yale to see what, if anything, had changed since I studied there. I wanted to understand why I had walked away from my dream, and why so many other women still walk away from theirs.