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Noncyclic covers of knot complements

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 نشر من قبل Nathan Broaddus
 تاريخ النشر 2004
  مجال البحث
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 تأليف Nathan Broaddus




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Hempel has shown that the fundamental groups of knot complements are residually finite. This implies that every nontrivial knot must have a finite-sheeted, noncyclic cover. We give an explicit bound, $Phi (c)$, such that if $K$ is a nontrivial knot in the three-sphere with a diagram with $c$ crossings and a particularly simple JSJ decomposition then the complement of $K$ has a finite-sheeted, noncyclic cover with at most $Phi (c)$ sheets.



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