Hidden symmetries and Dehn surgery on tetrahedral links

TL;DR

This paper investigates the existence of infinite families of knot complements with hidden symmetries obtained via Dehn fillings on hyperbolic link complements, providing algorithms and computational evidence for specific cases.

Contribution

It establishes criteria linking hidden symmetries to horoball packing symmetries and develops a SnapPy-based algorithm to test their existence, applied to various link complements.

Findings

No such families exist in the tetrahedral census links

The algorithm can effectively detect the absence of hidden symmetries

Results extend to certain cyclic covers of known manifolds

Abstract

Motivated by a question of Neumann and Reid, we study whether Dehn fillings on all but one cusp of a hyperbolic link complement can produce infinite families of knot complements with hidden symmetries which geometrically converge to the original link complement. We prove several results relating the existence of such an infinite family of knot complements with hidden symmetries to the existence of certain symmetries of the horoball packings associated to the original link. Using these results, we develop an algorithm which when run on SnapPy can test when such symmetries do not exist. We then use this SnapPy code and two utilities from \cite{orbcenpract} to show that for any given link in the tetrahedral census of Fominykh-Garoufalidis-Goerner-Tarkaev-Vesnin, no such family of Dehn fillings exists. We establish the same result for two infinite families of cyclic covers of the Berge manifold and the $6^2_2$-complement as well.