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Thurston norms of tunnel number-one manifolds

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 نشر من قبل Nicholas Vlamis
 تاريخ النشر 2018
  مجال البحث
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The Thurston norm of a 3-manifold measures the complexity of surfaces representing two-dimensional homology classes. We study the possible unit balls of Thurston norms of 3-manifolds $M$ with $b_1(M) = 2$, and whose fundamental groups admit presentations with two generators and one relator. We show that even among this special class, there are 3-manifolds such that the unit ball of the Thurston norm has arbitrarily many faces.



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