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arXiv · 1409.0324

Virtual Knot Cobordism

Louis H. Kauffman
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Abstract

This paper defines a theory of cobordism for virtual knots and studies this theory for standard and rotational virtual knots and links. Non-trivial examples of virtual slice knots are given. Determinations of the four-ball genus of positive virtual knots are given using the results of a companion paper by the author and Heather Dye and Aaron Kaestner. Problems related to band-passing are explained, and a theory of isotopy of virtual surfaces is formulated in terms of a generalization of the Yoshikawa moves.

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Louis H. Kauffman. 2014-09-01. Virtual Knot Cobordism. https://arxiv.org/abs/1409.0324

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