Computable bounds for Rasmussen's concordance invariant

Andrew Lobb

doi:10.1112/s0010437x10005117

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arXiv · 0908.2745

Computable bounds for Rasmussen's concordance invariant

Andrew Lobb

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Abstract

Given a diagram D of a knot K, we give easily computable bounds for Rasmussen's concordance invariant s(K). The bounds are not independent of the diagram D chosen, but we show that for diagrams satisfying a given condition the bounds are tight. As a corollary we improve on previously known Bennequin-type bounds on the slice genus.

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BibTeX RIS

Andrew Lobb. 2009-09-09. Computable bounds for Rasmussen's concordance invariant. https://doi.org/10.1112/s0010437x10005117

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