Kontogeorgis: Field of moduli versus field of definition for cyclic covers of the projective line

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Aristides Kontogeorgis
Field of moduli versus field of definition for cyclic covers of the projective line
Journal de théorie des nombres de Bordeaux, 21 no. 3 (2009), p. 679-693
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Résumé - Abstract

We give a criterion, based on the automorphism group, for certain cyclic covers of the projective line to be defined over their field of moduli. An example of a cyclic cover of the complex projective line with field of moduli $ℝ$ that can not be defined over $ℝ$ is also given.

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