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arXiv · alg-geom/9410030

Self-linking number of a real algebraic link

Oleg Viro
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Abstract

For a nonsingular real algebraic curve in the 3-dimensional projective space and sphere a new numeric characteristic is introduced. It takes integer values, is invariant under rigid isotopy, multiplied by -1 under mirror reflection. In a sense it is a Vassiliev invariant of degree 1 and a counter-part of a link diagram writhe.

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Oleg Viro. 1994-10-30. Self-linking number of a real algebraic link. https://arxiv.org/abs/alg-geom/9410030

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