The first thing that likely comes to a physicist’s mind when I say “turn the crank” is problem sets, and the student desire to find an equation or set of equations into which one can plug numbers and then, well, turn the crank. More about that some other time.

But what about the other kind of crank who turns up in physics: a person with an alternative theory of gravity who is convinced that he [I have yet to hear of a female physics crank] is right and Einstein was wrong? I’m talking about people typically without an academic background in the subject, whose ideas are, shall we say, non-mainstream. They often want their ideas to be validated by professionals in the field, and sometimes feel persecuted when they are not.

Since becoming a professor in a Physics & Astronomy department, my level of contact with cranks has definitely gone up. In the past year I have chatted on the phone with a pleasant older man who earnestly informed me that there was a “spirit world” hiding on the other side of Jupiter, talked in my office to a young man with a new theory of quantum spacetime, and deleted (mostly unread) more odd e-mails than I care to count. Their e-mails or treatises often have some physics-related vocabulary in them, and sometimes even equations, but put together in ways that make no sense. Certainly I haven’t yet seen a case where one of these folks proposed an experimental test of his ideas.

My question is – how should we, as members of the establishment, deal with such folks? Many of them are very thoughtful, polite people, and I think it’s only reasonable to treat them with courtesy. (If nothing else, they are fellow members of the society which supported our many years of training and now funds our research.) In general they are harmless, unlike cranks in medically-related fields, who can do serious damage to themselves or others. And of course there is the off chance that one of them will be right; there certainly have been cases in the history of science where “what everybody knows” turned out to be incorrect.  But I think it is fair to say that most of these people are expending their energies on something that is unlikely to ever pan out. Should we tell them this? Attempt to set them straight about the scientific method? Or ignore them and just be happy that they are interested enough in [their idea of] science to spend their time on it?

Discuss.