Say I want to look at the field extension Quot(Q[x,y]/y7−x) over Q(x) and then compute its Galois closure. How do I do that?
Ideally it could be done on the scheme-level (to define the scheme-morphism: (the projectivization of the affine plane curve y7−x) mapping to (the projective x-line); and then compute its Galois closure -- a scheme!). But I don't know how to implement either version.