Harmonic Galois theory for finite graphs
نویسندگان
چکیده
This paper develops a harmonic Galois theory for finite graphs, thereby classifying harmonic branched G-covers of a fixed base X in terms of homomorphisms from a suitable fundamental group of X together with G-inertia structures on X. As applications, we show that finite embedding problems for graphs have proper solutions and prove a Grunwald-Wang type result stating that an arbitrary collection of fibers may be realized by a global cover.
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