Incompressibility criteria for spun-normal surfaces

  title={Incompressibility criteria for spun-normal surfaces},
  author={Nathan M. Dunfield and Stavros Garoufalidis},
  journal={Transactions of the American Mathematical Society},
We give a simple sufficient condition for a spun-normal surface in an ideal triangulation to be incompressible, namely that it is a vertex surface with non-empty boundary which has a quadrilateral in each tetrahedron. While this condition is far from being necessary, it is powerful enough to give two new results: the existence of alternating knots with non-integer boundary slopes, and a proof of the Slope Conjecture for a large class of 2-fusion knots. While the condition and conclusion are… Expand

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