My guess is that they don't since it's thought that they might be possible, but here's why I'm asking this question: in the magnetic field created by a magnetic dipole, couldn't you place a magnetic monopole into the field (make sure it stays on the set path) and have it circulate continuously? I uploaded a picture, sorry for the crummy drawing, I just threw it together real quick in paint. Anyways, why wouldn't this work if a monopole existed? thanks for the help Edit: sorry just realized this probably shouldn't have gone in classical physics seeing as maxwell's equations predict magnetic monopoles don't exist. At least it's still part of electromagnetism. Sorry.