According to a deterministic many-worlds theory, free exists, and not only in the compatibilist sense, but also in the libertarian sense. The compatibilist account is that my action is fixed, but I would be able to do otherwise if I wanted to; it is just that I don't want to and can't want to. But in the many worlds theory, I can do either, not only if I wanted to but in reality: for according to the many words theory, in fact I do both, which proves that I can do each of them. So many-worlds is not compatibilist, but libertarian, despite the fact that it is deterministic. (In another way of putting it: from the point of view of the outside observer, it is deterministic; from the viewpoint of an observer who is about to split into two observers, it is libertarian.)