Why are there so few female physics faculty?

Analysis by the American Institute of Physics Statistical Research Center this summer by Susan White & Rachel Ivie questions whether the low percentage of women faculty in physics departments, and their absence from many departments, is evidence of a lack of equity for women.  The authors point out that the main factor is the small percentage of women in physics overall.  Given the small fraction of women overall, the argument goes, departments may be equitable in appointing women despite their small representation on the faculty.

In a later report on Women among Physics & Astronomy Faculty, the authors point out that in Physics, women are hired as assistant professors at rates well above their availability rate among doctoral recipients.  In 2007, 18% of PhDs in physics were awarded to women.  In 2010, 29% of newly hired assistant professors of physics were women (based on a survey with 93% response rate from departments).  One possible conclusion is that physics departments are working hard to improve gender equity, and we should be pleased with the results.  I've even heard some argue that departments are going out of their way to recruit women.

As a physics department head who worked hard to improve gender equity, I accept some of this analysis but not the conclusion that we've done enough.  In my experience, the higher percentage of women hired relative to the applicant pool reflects the higher quality of women applicants compared with men.  When the numbers of any population are smaller than "critical mass" -- a concept that involves support networks and encouragement by role models -- then those who make it through the constrictions of faculty advancement are distilled into superlative quality.  An example is the senior women in science at MIT, who are winners of the National Medal of Science and members of the National Academies at higher rates than their male counterparts.  When women who are uncertain whether they want the academic life are selectively discouraged to leave science, those who remain work harder, accomplish more, and are stronger applicants.  This is an unsurprising outcome, but not an equitable one.

In fact, the high quality and success of women in physics (and astronomy, whose representation among prize postdoctoral fellows has been high in recent years, leading to increasing appointment rates to faculty positions), suggests that departments could improve their quality if they were able to increase their applicant pools of women.

I agree with the final conclusion of White & Ivie, "While counting the number of departments with no women is not a valid measure of gender equity, we do not mean to provide a convenient explanation for departments that have no gender variation. Instead, the issue of gender equity in physics is more complex and nuanced. It cannot be distilled into any single measure."

So what are we to do?  I recommend that we redouble our efforts to create supportive environments for all students and postdocs, we continue to focus on quality mentoring and career development, we continue to recruit the best young people regardless of gender, and we learn from the successes of those programs where students and faculty thrive.  But let us not confuse thriving with surviving.