The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform

Gerhard Rosenberger - One of the best experts on this subject based on the ideXlab platform.

Johnson Jonathan - One of the best experts on this subject based on the ideXlab platform.

  • Two-Bridge Knots and Residual Torsion-Free Nilpotence
    2020
    Co-Authors: Johnson Jonathan
    Abstract:

    The residual torsion-free nilpotence of the Commutator Subgroup of a knot group has proven to be an important property with applications to ribbon concordance and bi-orderability. In a lecture, Mayland stated that a two-bridge knot group has a Commutator Subgroup which is a union of an ascending chain of parafree groups. In this case, a result of Baumslag would imply that the Commutator Subgroups of two-bridge knot groups are residually torsion-free nilpotent. However, the transcript of Mayland's lecture does not contain a complete proof, and later, Mayland and Murasugi stated that the transcript is "seriously marred by misprints and minor errors." This paper completes the proof of Mayland's assertion which had remained unfinished. This proof makes use of a modified version of a graph theoretic construction of Hirasawa and Murasugi in order to understand the structure of the Commutator Subgroup of a two-bridge knot group.Comment: 39 pages, 16 figure

  • Residual Torsion-Free Nilpotence, Bi-Orderability and Pretzel Knots
    2020
    Co-Authors: Johnson Jonathan
    Abstract:

    The residual torsion-free nilpotence of the Commutator Subgroup of a knot group has played a key role in studying the bi-orderability of knot groups. A technique developed by Mayland provides a sufficient condition for the Commutator Subgroup of a knot group to be residually-torsion-free nilpotent using work of Baumslag. In this paper, we apply Mayland's technique to several genus one pretzel knots and a family of pretzel knots with arbitrarily high genus. As a result, we obtain a large number of new examples of knots with bi-orderable knot groups. These are the first examples of bi-orderable knot groups for knots which are not fibered or alternating.Comment: 19 pages, 4 figure

Rubén A. Hidalgo - One of the best experts on this subject based on the ideXlab platform.

  • Torsion Free Commutator Subgroups of Generalized Coxeter Groups
    Results in Mathematics, 2005
    Co-Authors: Rubén A. Hidalgo, Gerhard Rosenberger
    Abstract:

    In this note we consider generalized Coxeter groups and we study the problem of when their Commutator Subgroup is torsion free. As a consequence we describe all (i) Coxeter groups, (ii) triangle groups and (iii) index two orientation preserving Subgroups of the finite co-volume hyperbolic Coxeter tetrahedra, for which the Commutator Subgroup is torsion free.

  • kleinian groups with common Commutator Subgroup
    Complex Variables and Elliptic Equations, 1995
    Co-Authors: Rubén A. Hidalgo
    Abstract:

    In this paper, we obtain a certain rigidity property for Kleinian groups. This asserts that if F and G (both non-elementary torsion-free Fuchsian groups) and [F F] = [G G],then F= G (all equalities are taken in the sense of Mobius transformations). This result is connected to Torelli's theorem (for closed Riemann surfaces) and can be a step in understanding an equivalent for more general type of Riemann surfaces.

R V Skuratovskii - One of the best experts on this subject based on the ideXlab platform.

Witold Tomaszewski - One of the best experts on this subject based on the ideXlab platform.