Exact computation for existence of a knot counterexample


  • K. Marinelli University of Connecticut
  • T. J. Peters University of Connecticut




knot theory, isotopy, parametric curve


Previously, numerical evidence was presented of a self-intersecting Bezier curve having the unknot for its control polygon. This numerical demonstration resolved open questions in scientic visualization, but did not provide a formal proof of self-intersection. An example with a formal existence proof is given, even while the exact self-intersection point remains undetermined.


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Author Biographies

K. Marinelli, University of Connecticut

Department of Computer Science & Engineering

T. J. Peters, University of Connecticut

Department of Computer Science & Engineering


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How to Cite

K. Marinelli and T. J. Peters, “Exact computation for existence of a knot counterexample”, Appl. Gen. Topol., vol. 20, no. 1, pp. 251–264, Apr. 2019.



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