Carrigan is a particle physicist. His ET idea might be flaky but presumably his day job is particle physics. To become a particle physicist, you would first get an undergraduate degree in physics (or a related major with plenty of physics in it) then you would go to graduate school for your PhD in particle physics. It's a highly mathematical and difficult subject. To complete your PhD you must write original research of a quality sufficient to be published in a recognized, peer-reviewed scientific journal. Then you're on the job market. Some years, the market is favorable, and you'll get a position, perhaps at a college or university, perhaps (as Carrigan has) a research lab (these are often sponsored by consortia of universities or the government). But other years, unless you're particularly good, you might find yourself programming computers for a living.
Well, there's a big difference between knowledge and wisdom, isn't there?
That's the problem with PhD's, isn't it... I have known a few of them who may have been brilliant in a particular subject, but didn't have enough sense to know when they had gone for too long without taking a bath. Wonder whether this guy has a similar "impairment"...