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arXiv · 2108.13546

Extended genus field of cyclic Kummer extensions of rational function fields

Edgar Omar Curiel-Anaya·Myriam Rosalía Maldonado-Ramírez·Martha Rzedowski-Calderón
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Abstract

For a cyclic Kummer extension $K$ of a rational function field $k$ is considered, via class field theory, the extended Hilbert class field $K_H^+$ of $K$ and the corresponding extended genus field $K_g^+$ of $K$ over $k$, along the lines of the definitions of R. Clement for such extensions of prime degree. We obtain $K_g^+$ explicitly. Also, we use cohomology to determine the number of ambiguous classes and obtain a reciprocity law for $K/k$. Finally, we present a necessary and sufficient condition for a prime of $K$ to decompose fully in $K_g^+$.

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Edgar Omar Curiel-Anaya, Myriam Rosalía Maldonado-Ramírez, Martha Rzedowski-Calderón. 2021-08-30. Extended genus field of cyclic Kummer extensions of rational function fields. https://arxiv.org/abs/2108.13546

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