Tuesday, February 5, 2013

On the two body problem

Figure 1: The two-body problem. Image taken from this blog


In academia there is something called the "two-body problem." The original two-body problem involves the gravitational interaction between two massive bodies, e.g. a planet orbiting a star. This is a problem in the mathematical sense, as in something interesting about the universe that we would like to figure out. This classical two-body problem has a solution, but interestingly it is in the form of a transcendental equation that can only be solved numerically. But when done so, it looks like this. Pretty nice, huh?

It turns out that there's an even more difficult two-body problem in science academia, but this one has to do with the attraction between two humans (cf Figure 1 above for a succinct description). The problem arises when one or both individuals are academics seeking post-graduate job positions. The problem, in a traditional sense of the word, is related to the fact that academia has been honed and perfected over the centuries to accommodate only a specific type of coupling. If you are an academic and in a relationship, there is a closed-form solution to the two-body problem if and only if the partner/spouse is not also an academic and has the ability/willingness to move every 2-3 years over the next six years while academic partner takes various postdocs and/or other job positions. Personally, I was fortunate to find this "solution." Most do not.


A further complication from the standpoint of young academic couples is that there is often only one or at most a few available/desirable job openings per institution per year. This means that it is highly unlikely that the coupled academics will find their ideal job position at the same institution. However, if they do solve the problem at the postdoc level, it is very unlikely that it'll happen again at the professor level. Think of multiplying two or more small probabilities; the result is a very small chance. On the other hand, if you have a traditional (read: 1950's-era) family, none of this is really a problem. One partner pursues their career, the other raises the family, and the solution is not only closed-form, but elegantly analytic.

However, in modern times there have arisen a whole host of complications. The primary one is that as more and more women enter graduate programs, more and more couplings are occurring within said grad programs---hot nerd-on-nerd action, if you will. In what follows, please allow me to apply a cold scientific analysis to an inherently human/emotional process (I'm already bracing myself or angry commenters noting that not all women date men in academia. Settle down nerds, I recognize and hereby acknowledge the difference between a simplifying assumption and reality, the difference between the mean and the dispersion of a distribution of human behavior.)

Since the male-female ratio in most grad astro programs is 2:1---which is very high among the sciences, but still far from parity---there will be more women with two-body problems than men, under the simplifying assumption that every woman couples to a man. For every 3 intradepartmental pairings, there are four men available (forced) onto online dating services, night clubs, etc. where they can meet a non-academic. As the male-female ratio increases, the frequency of two-body problems among women increases. This assumption is valid, in my opinion, given that astro grad students spend the majority of their waking hours in their offices doing problem sets, reading papers, and tracking down bugs in their data reduction and numerical integration codes, instead of hanging out where non-academic, single people congregate. And if one's soulmate is not in the same department, there's always Bio or Engineering across the street!

This hypothesis gives rise to a few predictions:
  1. The majority of women in science will be in a relationship with another academic. Here's a test providing confirmation of this prediction.
  2. The unequal male/female ratio will result in more women than men facing a two-body problem
  3. Societal norms and/or other pressures will result in the woman giving up her career more frequently than the man giving up his. Anecdotally, but very obviously, I've noticed that the men in two-body situations tend to be 1-4 years older than their partner, which means they are more established when the tough decision-time comes. With a man in an established job further along in his career, it is often the woman who gives up rolling the dice on a future opportunity in favor of the sure-thing right now with her partner’s job offer.
  4. There will be a higher attrition rate among women than among men in academia, causing the male-female ratio to increase from grad school, to postdoc, to professor.
  5. The refusal of science programs to acknowledge and address this problem will exacerbate the gender disparity among their faculty.

Based on my personal observations during travels to various institutions, these predictions seem to hold up. The vast majority of my female friends/colleagues are in relationships with another academics, quite frequently with other astronomers. And far from being just a cute name given to a societal phenomenon, the two-body problem is a Problem with a capital P.

Figure from Dual Career Academic Couples: What Universities Need to Know (PDF)
I can't imagine cutting my astronomy career short at this phase in my life, so I can only imagine how difficult it is for people to be forced to decide between their careers and their relationships. I've heard of women being told, "Your spouse has an excellent job opportunity here. Would it be so bad to give up your career?" I have to admit that I've entertained such thoughts in the past. But I find it doesn't work when I apply this reasoning to myself. When I think about my passion for astronomy, and how my research is what causes me to go to bed late and wake up early, there's just no way I could imagine giving up my career and still finding full satisfaction in life. I'm a trained slayer of hard problems, and I live to to drive big telescopes across the sky. I'm also passionate about undergraduate and grad education of the type that can only be implemented effectively as a professor. How could I just give that up? So, no, it's not at all an option to ask a coupled scientist to give up their careers.

When couples are able to hold onto their pursuits, long-distance relationships are very common, which puts strains not only on the individuals, but also on their science. Being away from one’s partner for extended periods of time leads to stress and anxiety, whcih negatively impacts day-to-day work. Excellent candidates pass up opportunities at top institutions (justifiably) to stay with their spouse. Top profs at leading institutions drop out at the peak of their games to find a solution to the two-body problem. Postdocs pass up fellowship offers to stay close to home. I really wish these weren't the choices that young scientists have to face. Our field would be much happier with a closed-form solution to the two-body problem.

As we in astronomy begin to embrace diversity as a key ingredient for excellence, we must find a robust solution to the two-body problem. To keep the conversation moving forward, here are some solutions I have heard suggested or come up with on my own:

  1. Make postdoctoral fellowships last 4-5 years, rather than 2-3. The extra years relieve pressure and stress on couples to immediately begin searching for the next job and reduces the number of times a postdoc must move before (hopefully) settling into a more permanent professorship.
  2. Restructure job searches to allow for two-body hires. I've heard it argued that this is undesirable because it would require sacrifices in "excellence" to hire a spouse that isn't as "excellent" as the primary hire. But what good is hiring an excellent individual when they will be looking for a more accommodating position from day-one after starting at your university? How much excellence can be traded for an unhappy, loosely-bound workforce? On the flip side, think about how much more loyal your employees will be if hired together. You better believe they'll work harder than anyone else in your dept, and be far less likely to be enticed by competive offers later (immunity to poaching is valuable, no?). Also, think of the message you send to your entire workforce when you demonstrate the value of family security in your workforce.
  3. Coordinate among departments to make mixed-academic hires. One department might have to make a bit of a sacrifice along the (percieved) excellence dimension this time, but think of what can be gained the next time around when their top applicant is coupled to another academic. Astronomy is not the only field facing the problem.
  4. Recognize the considerable uncertainty in judging excellence in the traditional sense. How many previously-identified excellent hires didn't attain tenure at your institution and other top universities in the past 20 years? If hiring committees can miss that badly in one direction, why not hire the person who is deemed an 8/10 on your scale in order to retain the 10/10 in your dept now, with the recognition that that 8.0 is really 8 +/- 1

What have I missed? Discuss!