A flow in three-dimensions is universal if the periodic orbits contains all knots and links. Universal flows were shown to exist by Ghrist, and can be constructed by means of templates. Likewise, a planar diffeomorphism is universal if it has a suspension flow which is a universal flow. In this paper we prove the existence of a homoclinic trellis type for which any representative diffeomorphism is universal. This trellis type is remarkable in that it has zero entropy, and only two homoclinic intersection points.
, , ,
SS中的纽结和连接(高维, 见57Q45) (msc 57M25), ,
World Scientific
Journal of Knot Theory and its Ramifications
Computational Topology for Systems and Control
Scientific Computing

Collins, P.J. (2007). Universal Trellises. Journal of Knot Theory and its Ramifications, 16(4), 97–114.