Substituting "may be" for "are", and that's precisely what science fiction is about. And we don't, in fact, know for certain that it's physically possible to transfer human consciousness to anything other than the specific body in which it arises.
Dave
Sure, but I wasn't claiming that transferring consciousness was possible, only copying the system (which we do know would result in a copy that had the same properties). A lot of discussion in this thread has been about whether or not that would actually equate to a transfer of consciousness, and in general my view is that it wouldn't.
I don't think there's anything less scientific about discussing uploading than say potential battery technologies, next generation nuclear reactors, what the most likely avenue to nuclear fusion is, or colonizing Mars. Some of those are more or less well understood, but I think each of those topics (and this one) are entirely suitable to this subsection of the forum and certainly aren't supernatural in nature.