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arXiv · 0710.3627

Homotopy on spatial graphs and generalized Sato-Levine invariants

Ryo Nikkuni
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Abstract

Edge-homotopy and vertex-homotopy are equivalence relations on spatial graphs which are generalizations of Milnor's link-homotopy. Fleming and the author introduced some edge (resp. vertex)-homotopy invariants of spatial graphs by applying the Sato-Levine invariant for the constituent 2-component algebraically split links. In this paper, we construct some new edge (resp. vertex)-homotopy invariants of spatial graphs without any restriction of linking numbers of the constituent 2-component links by applying the generalized Sato-Levine invariant.

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Ryo Nikkuni. 2008-12-27. Homotopy on spatial graphs and generalized Sato-Levine invariants. https://doi.org/10.1007/s13163-009-0007-x

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