English

Taut foliations from double-diamond replacements

Geometric Topology 2019-12-13 v2

Abstract

A 3-manifold is foliar if it supports a codimension-one co-oriented taut foliation. Suppose MM is an oriented 3-manifold with connected boundary a torus, and suppose MM contains a properly embedded, compact, oriented, surface RR with a single boundary component that is Thurston norm minimizing in H2(M,M)H_2(M, \partial M). We define a readily recognizable type of sutured manifold decomposition, which for notational reasons we call double-diamond taut, and show that if RR admits a double-diamond taut sutured manifold decomposition, then every boundary slope except one is strongly realized by a co-oriented taut foliation; that is, the foliation intersects M\partial M transversely in a foliation by curves of that slope. In the case that MM is the complement of a knot κ\kappa in S3S^3, the exceptional filling is the meridional one, and hence κ\kappa is persistently foliar, by which we mean that every non-trivial slope is strongly realized; hence, restricting attention to rational slopes, every manifold obtained by non-trivial Dehn surgery along κ\kappa is foliar. In particular, if RR is a Murasugi sum of surfaces R1R_1 and R2R_2, where R2R_2 is an unknotted band with an even number 2m42m\ge 4 of half-twists, then κ=R\kappa= \partial R is persistently foliar.

Keywords

Cite

@article{arxiv.1907.01899,
  title  = {Taut foliations from double-diamond replacements},
  author = {Charles Delman and Rachel Roberts},
  journal= {arXiv preprint arXiv:1907.01899},
  year   = {2019}
}

Comments

19 pages, 16 figures. Clarifications, corrections, improvements to exposition; numerous minor editorial revisions; two additional figures; some additional references; results unchanged. arXiv admin note: text overlap with arXiv:1905.04838

R2 v1 2026-06-23T10:11:07.728Z