Is it a mistake to talk about hobbies in a job application? According to Sean Carroll, a famous cosmologist and tenured professor, 


  Don’t be too well known outside the field. I hate to say this, but the evidence is there: if you have too high of a public profile, people look at you suspiciously. Actual quote: “I’m glad we didn’t hire Dr. X; he spends too much time in the New York Times and not enough time in the lab.” And that’s the point — it’s not that people are jealous that you are popular, it’s that they are suspicious you care about publicity more than you do about research. Remember the Overriding Principle.


According to an opinion piece by Manil Suri published in the New York Times, in science it is also not appropriate to talk about hobbies. Manil Suri is a famous scholar, his description of the situation in academia is worrying, and gives the impression that behavior is constrained and under close scrutiny. Being too expressive of personal identity can be viewed as running counter to scientific neutrality. In competitive venues, where complete immersion in one’s field might be the promoted ideal, the mention of an extracurricular pursuit can even be seized upon as a lack of commitment. I remember a young mathematician at a prestigious research institute sharing his love for piano playing after hearing I wrote fiction. “Don’t tell anyone in my department I own a piano,” he requested in the next breath. This is a shock to me because I perceived the STEM field as most openminded. 

Am I hurting my chances by answering honestly about hobbies and extracurricular and social engagement activities? I work in a STEM field.
There is a time and a place for everything. When evaluating your application to determine if you’re going to be one of the half dozen or so people who might get on the short list, your hobbies aren’t going to rate very high in the decision-making process, unless they suggest that they’re going to pull you away from your work too much.

But I’d also rather not work with a potential colleague who is so focused on their careers that they give up being someone you want to work with. Having hobbies and interests that have nothing to do with your daily job make you a better person, and it’s something you can talk about during a phone or in-person interview. 

In the specific case you’re asked, then that means it’s something they decided they do want to know about and you should answer candidly.