Lifting Galois covers of algebraic curves
نویسنده
چکیده
(1b) Question. For which pairs (C0,H) does a lift exist? Note that the lifting problem for C0 is formally smooth. However we will see that in general the lifting problem for (C0,H) can be obstructed; in some cases a lifting does not exist, in several cases ramification in R is needed to make a lifting possible. In order to have a positive answer to this question it suffices to consider the case where κ = k, an algebraically closed field; however if we insist on the extra property R to be normal,
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