Geodesic
GENERALISED FERMAT HYPERMAPS AND GALOIS ORBITS
Glasgow mathematical journal, Tome 51 (2009) no. 2, pp. 289-299

Voir la notice de l'article provenant de la source Cambridge University Press

We consider families of quasiplatonic Riemann surfaces characterised by the fact that – as in the case of Fermat curves of exponent n – their underlying regular (Walsh) hypermap is an embedding of the complete bipartite graph Kn,n, where n is an odd prime power. We show that these surfaces, regarded as algebraic curves, are all defined over abelian number fields. We determine their orbits under the action of the absolute Galois group, their minimal fields of definition and in some easier cases their defining equations. The paper relies on group – and graph – theoretic results by G. A. Jones, R. Nedela and M. Škoviera about regular embeddings of the graphs Kn,n [7] and generalises the analogous results for maps obtained in [9], partly using different methods.
DOI : 10.1017/S0017089509004972
Mots-clés : Primary 14H45, secondary 14H25, 14H30, 14H55, 05C10, 05C25, 30F10, 30F35 
COSTE, ANTOINE D.; JONES, GARETH A.; STREIT, MANFRED; WOLFART, JÜRGEN. GENERALISED FERMAT HYPERMAPS AND GALOIS ORBITS. Glasgow mathematical journal, Tome 51 (2009) no. 2, pp. 289-299. doi: 10.1017/S0017089509004972
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     journal = {Glasgow mathematical journal},
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