Thinking about leaving industry job and taking up a postdoc This is a follow-up to the question I posted about a year ago: How much damage would I be incurring if I turn down an informal postdoc offer?

My situation: I moved to industry about 6 months ago after declining a postdoc offer because I wanted to have some money and geographic flexibility to take care  of a sick family member. However, moving to the industry has given me a huge identity crisis because I was passionate about my research and the scientific community I was part of. Now I am itching to just take the postdoc and I got to know that the professor is still looking. I am wondering how I would approach him or has the damage been done already? The word is out that I have transitioned to the dark side and folks that I knew in grad school (including my grad school advisor) have begun to treat me as an outsider. Not sure how taking up a postdoc position would affect me in terms of recommendations and academic relationships. Anyone ever done this? How did it go?

Edit: My PhD was in geoscience.
I am in a different field (maths), but I know the stories of several people who went to work in unrelated industry jobs after their PhD, only to decide after a few months to return to academia. It never seemed to have hurt them, but there is of course a danger of survivorship bias, as I never got to know those who failed.

Since it does not seem like you actively burned bridges but only declined offers, I would simply approach the professor with a bit of humility. You made a mistake, but you are willing to correct it and six months is a short time in academia anyway. To add to that there is less danger of losing you to industry now than there is for a post-doc who hasn't tried it yet.

Concerning the "dark side" jokes, with most people they are merely that, namely jokes, so I wouldn't worry that much. They didn't really move away from you, you did move away from them. After all, with you in industry, there were simply no more research collaborations to be had and less of common interests.