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If a morphism of curves induces Galois extension of function fields, does the galois

Suppose f:XYf:X \rightarrow Y is a non-constant morphism of smooth projective curves defined over an algebraically closed field. Suppose that the corresponding field extension K(X)/K(Y)K(X)/K(Y) is Galois.

Does Gal(K(X)/K(Y))\text{Gal}(K(X)/K(Y)) act transitively on the fibers of f f?

More specifically if f(P)=f(Q) f(P)=f(Q) then is there a gGal(K(X)/K(Y) g \in \text{Gal}(K(X)/K(Y) such that the induced automorphism σg \sigma_g of X X maps P P to Q Q?

I would just like a hint if possible something for me to ponder about thanks!


:eek: I can usually at least understand the question, even if I can't necessarliy help, but not that one.

DFranklin, or @RichE are the two who spring to mind as most likely to be able to assist.
(edited 6 years ago)
Reply 3
Thanks for looking but I have an email from my professor now so it is understood.

Typical I post on stack and email him wait and hear nothing back post on here and then he gets back to me haaaa.
Original post by ghostwalker
:eek: I can usually at least understand the question, even if I can't necessarliy help, but not that one.

DFranklin, or @RichE are the two who spring to mind as most likely to be able to assist.
Yeah, past my competence too, I'm afraid...
Original post by poorform
Does Gal(K(X)/K(Y))\text{Gal}(K(X)/K(Y)) act transitively on the fibers of f f?


A contender for an immediate place in the Top 10 of academic questions posted on TSR.

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