We gratefully acknowledge support from
the Simons Foundation and member institutions.
Full-text links:

Download:

Current browse context:

math.GT

Change to browse by:

References & Citations

Bookmark

(what is this?)
CiteULike logo BibSonomy logo Mendeley logo del.icio.us logo Digg logo Reddit logo

Mathematics > Geometric Topology

Title: Taut foliations, braid positivity, and unknot detection

Abstract: We study positive braid knots (the knots in the three-sphere realized as positive braid closures) through the lens of the L-space conjecture. This conjecture predicts that if $K$ is a non-trivial positive braid knot, then for all $r < 2g(K)-1$, the 3-manifold obtained via $r$-framed Dehn surgery along $K$ admits a taut foliation. Our main result provides some positive evidence towards this conjecture: we construct taut foliations in such manifolds whenever $r<g(K)+1$. As an application, we produce a novel braid positivity obstruction for cable knots by proving that the $(n,\pm 1)$-cable of a knot $K$ is braid positive if and only if $K$ is the unknot. We also present some curious examples demonstrating the limitations of our construction; these examples can also be viewed as providing some negative evidence towards the L-space conjecture. Finally, we apply our main result to produce taut foliations in some splicings of knot exteriors.
Comments: 91 pages, 49 figures, 5 tables, 1 flowchart, 1 appendix
Subjects: Geometric Topology (math.GT)
Cite as: arXiv:2312.00196 [math.GT]
  (or arXiv:2312.00196v1 [math.GT] for this version)

Submission history

From: Siddhi Krishna [view email]
[v1] Thu, 30 Nov 2023 21:14:36 GMT (1541kb,D)

Link back to: arXiv, form interface, contact.