Belyi-extending Maps and the Galois Action on ̂π1(p 1 C \ {0, 1, ∞})
نویسنده
چکیده
We study the action of the absolute Galois group Gal(Q̄/Q) on the algebraic fundamental group of P1C\{0, 1,∞}. We define a class of functions called Belyi-extending maps, and using them we are able to (1) give new Galois invariants of Grothendieck’s dessins d’enfants and (2) give explicit relations on the fσ in terms of which the Galois action on π̂1(P 1 C \ {0, 1,∞}) is known.
منابع مشابه
Belyi-extending Maps and the Galois Action on Dessins D’enfants
We study the absolute Galois group by looking for invariants and orbits of its faithful action on Grothendieck’s dessins d’enfants. We define a class of functions called Belyi-extending maps, which we use to construct new Galois invariants of dessins from previously known invariants. Belyiextending maps are the source of the “new-type” relations on the injection of the absolute Galois group int...
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