Diagram uniqueness of even plats

Yoav Moriah; Jessica S. Purcell

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arXiv · 1803.00685

Diagram uniqueness of even plats

Yoav Moriah·Jessica S. Purcell

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Abstract

Every knot has a plat projection, obtained by closing up a braid with bridges. The plat projection is determined by the number of strands and the number of rows of twist regions in the braid, and an integer number of crossings in each twist region. In recent work, we showed that under certain restrictions, including that the number of rows is odd, a minimal width plat projection is unique. In this paper we extend the results to even plats. Using new arguments, we show that if each of their twist regions contains at least three crossings, and their length is sufficiently long with respect to their width, then the projection is unique. This essentially "doubles" the set of knots for which such diagrams classify the links.

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Yoav Moriah, Jessica S. Purcell. 2018-03-02. Diagram uniqueness of even plats. https://arxiv.org/abs/1803.00685

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