A $(1,1)$-knot in the 3-sphere is a knot that admits a 1-bridge presentation with respect to a Heegaard torus in $\mathbb{S}^{3}$. A new parameterization of $(1,1)$-knots distinct from the classical ones is introduced. This parameterization is obtained from minimal-length representatives of homotopy classes of arcs in the mutipunctured plane. In the particular case of satellite $(1,1)$-knots, it is proven that the introduced parameterization is essentially unique. A generalization of this parameterization to the family of $(g,1)$-knots for any $g\geq 1$ is proposed.
We present a short proof of a theorem of Tanaka that if a composite ribbon knot admits a symmetric union presentation with one twisting region, then it has a non-trivial knot and its mirror image as connected summands.
This paper describes a Dehn surgery approach to generating asymmetric hyperbolic manifolds with two distinct lens space fillings. Such manifolds were first identified in work of Dunfield-Hoffman-Licata as the result of a computer search of the SnapPy census, but the current work establishes a topological framework for constructing vastly many more such examples. We introduce the notion of a ``jointly primitive'' presentation of a knot and show that a refined version of this condition ``longitudinally jointly primitive'' is equivalent to being surgery dual to a $(1,2)$--knot in a lens space. Th…
It is known that a presentation of the knot group of a branched twist spin is obtained from a Wirtinger presentation of the original 1-knot group by adding a generator corresponding to a regular orbit of the circle action and a certain relator. In particular, the additional generator is an element of the center of the knot group. In this paper, we focus on ${\rm SL}_2(\mathbb{Z}_3)$-representations and dihedral group representations. For the former case, we give a sufficient condition for the existence of an ${\rm SL}_2(\mathbb{Z}_3)$-representation for a branched twist spin. For the latter ca…
本文证明了M. J. Dunwoody是透镜空间的循环覆盖（最终为$\bf S^3$），在亏格1-桥结上分支。因此，我们对Dunwoody猜想给出了肯定的回答，即一个宽子类的所有元素都是$\bf S^3$在一个纽结上分支的循环覆盖.此外，我们表明，所有的分支循环覆盖的2桥结属于这个子类，这意味着基本群的每个分支循环覆盖的2桥结承认一个几何循环介绍。
Given a braid presentation $D$ of a hyperbolic knot, Hikami and Inoue consider a system of polynomial equations arising from a sequence of cluster mutations determined by $D$. They show that any solution gives rise to shape parameters and thus determines a boundary-parabolic $\mathrm{PSL}(2,\mathbb{C})$-representation of the knot group. They conjecture the existence of a solution corresponding to the geometric representation. In this paper, we show that a boundary-parabolic representation $ρ$ arises from a solution if and only if the length of $D$ modulo $2$ equals the obstruction to lifting $…
这是Gordon-Reid [Tangle decompositions of tunnel number one knots and links，J.纽结理论及其分支，4（1995）389-409]和Thompson [Thin position and bridge number for knots in the 3-sphere，Topology，36（1997）505-507]的定理的结果，如果将一个隧道号结置于薄的位置，也会在桥上。我们表明，在这样一个薄的介绍，隧道可以使水平，使它位于一个水平的领域。这解决了Morimoto提出的一个问题[A note on unknotting tunnels for 2-bridge knots，Bulletin of Faculty of Engineering Takushoku University，3（1992）219-225]，他表明，如果已知任何unknotting tunnel都可以被制成水平的，那么用于2-bridge knots的unknotting tunnel的（现在已知的）分类将很快出现。
The Wirtinger number of a virtual link is the minimum number of generators of the link group over all meridional presentations in which every relation is an iterated Wirtinger relation arising in a diagram. We prove that the Wirtinger number of a virtual link equals its virtual bridge number. Since the Wirtinger number is algorithmically computable, it gives a more effective way to calculate an upper bound for the virtual bridge number from a virtual link diagram. As an application, we compute upper bounds for the virtual bridge numbers and the quandle counting invariants of virtual knots with…
