Knotted solid tori in contact manifolds

J John B. Etnyre (School of Mathematics, Georgia Institute of Technology) Y Youlin Li (School of Mathematical Sciences, Shanghai Jiao Tong University) B Bülent Tosun (Department of Mathematics, University of Alabama)

Abstract

In this paper, we study solid tori in contact manifolds. Specifically, we study the contact width of a knot type and give criteria for when it can be explicitly computed. We also prove there are many “nonthickenable” tori in many knot types. These tori are frequently essential in the study of Legendrian and transverse knot theory and tight contact structures on manifolds obtained by surgery on the knot. Previously, nonthickenable tori have only been observed for iterated torus knots in S 3 and were thought to be rare. We show that they are quite common, exist in other manifolds, and even for a hyperbolic knot in S 3 . We also make and highlight several conjectures about the general nature of knots in contact manifolds.

Article Details

Volume / Issue Vol. 123, Issue 26
Published June 30, 2026
ISSN 0027-8424
Publisher National Academy of Sciences

Authors (3)

J

John B. Etnyre

School of Mathematics, Georgia Institute of Technology

Y

Youlin Li

School of Mathematical Sciences, Shanghai Jiao Tong University

B

Bülent Tosun

Department of Mathematics, University of Alabama