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arXiv · 1703.10537

On the third homotopy group of Orr's space

Emmanuel D. Farjoun·Roman Mikhailov
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Abstract

K. Orr defined a Milnor-type invariant of links that lies in the third homotopy group of a certain space $K_\omega.$ The problem of non-triviality of this third homotopy group has been open. We show that it is an infinitely generated group. The question of realization of its elements as links remains open.

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Emmanuel D. Farjoun, Roman Mikhailov. 2017-03-30. On the third homotopy group of Orr's space. https://doi.org/10.2140/agt.2018.18.569

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