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Characterizing covers via simple closed curves

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 نشر من قبل Tarik Aougab
 تاريخ النشر 2020
  مجال البحث
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Given two finite covers $p: X to S$ and $q: Y to S$ of a connected, oriented, closed surface $S$ of genus at least $2$, we attempt to characterize the equivalence of $p$ and $q$ in terms of which curves lift to simple curves. Using Teichmuller theory and the complex of curves, we show that two regular covers $p$ and $q$ are equivalent if for any closed curve $gamma subset S$, $gamma$ lifts to a simple closed curve on $X$ if and only if it does to $Y$. When the covers are abelian, we also give a characterization of equivalence in terms of which powers of simple closed curves lift to closed curves.



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