Movie moves for singular link cobordisms in 4-dimensional space

Carmen Caprau

doi:10.1142/s0218216516500139

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arXiv · 1507.04077

Movie moves for singular link cobordisms in 4-dimensional space

Carmen Caprau

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Abstract

Two singular links are cobordant if one can be obtained from the other by singular link isotopy together with a combination of births or deaths of simple unknotted curves, and saddle point transformations. A movie description of a singular link cobordism in 4-space is a sequence of singular link diagrams obtained from a projection of the cobordism into 3-space by taking 2-dimensional cross sections perpendicular to a fixed direction. We present a set of movie moves that are sufficient to connect any two movies of isotopic singular link cobordisms.

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Carmen Caprau. 2015-07-15. Movie moves for singular link cobordisms in 4-dimensional space. https://doi.org/10.1142/s0218216516500139

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