Of course, it is impossible to create something ex nihilo. [Citation needed.] But, for a moment, let's pretend it's possible. Would there be a halachos issue with doing so on Shabbos? (I'm assuming yes because, A, even Hashem refrained from doing so, and, B, it's probably the ultimate violation of Boneh and Makeh Bepatish ever.)
Would a question such as the above be allowed? As I've just demonstrated, such questions may very well be answerable, though I'm sure many aren't.