Decomposability problem on branched coverings

N. A. V. Bedoya   ; D. L. Gonçalves

Sbornik. Mathematics, Tome 201 (2010) no. 12, pp. 1715-1730

Résumé

Given a branched covering of degree $d$ between closed surfaces, it determines a collection of partitions of $d$, the branch data. In this work we show that any branch data are realized by an indecomposable primitive branched covering on a connected closed surface $N$ with $\chi(N) \leq 0$. This shows that decomposable and indecomposable realizations may coexist. Moreover, we characterize the branch data of a decomposable primitive branched covering. Bibliography: 20 titles.

Détail

Keywords: branched coverings, permutation groups.

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