He was planning to go into academia, but ended up abandoning his PhD ABD because he got exposed to the negative interpersonal politics that can happen in academ

He was planning to go into academia, but ended up abandoning his PhD ABD because he got exposed to the negative interpersonal politics that can happen in academia and realized that was not for him. So he went to go work a dozen years at a hedge fund and then retire to be a stay at home dad. His primary research interest was logical frameworks, constructive mathematics, etc. His PhD topic was on using linear logic to verify concurrent programs.