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Related papers: Virtual Knot Cobordism

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We introduce stable equivalence classes of oriented links in orientable three-manifolds that are orientation $I$-bundles over closed but not necessarily orientable surfaces. We call these twisted links, and show that they subsume the…

Geometric Topology · Mathematics 2014-10-01 Mario O. Bourgoin

A pseudodiagram is a diagram of a knot with some crossing information missing. We review and expand the theory of pseudodiagrams introduced by R. Hanaki. We then extend this theory to the realm of virtual knots, a generalization of knots.…

Geometric Topology · Mathematics 2011-09-20 Allison Henrich , Noel MacNaughton , Sneha Narayan , Oliver Pechenik , Jennifer Townsend

We introduce Tristram-Levine signatures of virtual knots and use them to investigate virtual knot concordance. The signatures are defined first for almost classical knots, which are virtual knots admitting homologically trivial…

Geometric Topology · Mathematics 2021-03-16 Hans U. Boden , Micah Chrisman , Robin Gaudreau

We extend the cobordism based categorification of the virtual Jones polynomial to virtual tangles. This extension is combinatorial and has semi-local properties. We use the semi-local property to prove an applications, i.e. we give a…

Geometric Topology · Mathematics 2016-02-02 Daniel Tubbenhauer

We study groups of some virtual knots with small number of crossings and prove that there is a virtual knot with long lower central series which, in particular, implies that there is a virtual knot with residually nilpotent group. This…

Geometric Topology · Mathematics 2020-07-21 Valeriy G. Bardakov , Neha Nanda , Mikhail V. Neshchadim

This paper introduces two virtual knot theory ``analogues'' of a well-known family of invariants for knots in thickened surfaces: the Grishanov-Vassiliev finite-type invariants of order two. The first, called the three loop isotopy…

Geometric Topology · Mathematics 2013-09-13 Micah W. Chrisman , H. A. Dye

This paper extends the construction of invariants for virtual knots to virtual long knots and introduces two new invariant modules of virtual long knots. Several interesting features are described that distinguish virtual long knots from…

Geometric Topology · Mathematics 2007-06-01 Andrew Bartholomew , Roger Fenn , Naoko Kamada , Seiichi Kamada

In this paper we show how generalized quaternions, including 2X2 matrices, can be used to find solutions of a non-commuting equation intimately connected with braid groups. These solutions can then be used to find polynomial invariants of…

Geometric Topology · Mathematics 2009-09-29 Roger Fenn

We explain the notion of a grope cobordism between two knots in a 3-manifold. Each grope cobordism has a type that can be described by a rooted unitrivalent tree. By filtering these trees in different ways, we show how the Goussarov-Habiro…

Geometric Topology · Mathematics 2010-08-25 Jim Conant , Peter Teichner

We construct cobordisms of small genus between torus knots and use them to determine the cobordism distance between torus knots of small braid index. In fact, the cobordisms we construct arise as the intersection of a smooth algebraic curve…

Geometric Topology · Mathematics 2017-03-16 Peter Feller

Flat virtual links are some variant of links, and semiquandles are counterparts of quandles or biquandles, which axiomize the Reidemeister-like moves. In this paper, we give some example of semiquandle and introduce an invariant for flat…

Geometric Topology · Mathematics 2024-11-08 Nozomu Sekino

We generalize the Wriggle polynomial, first introduced by L. Folwaczny and L. Kauffman, to the case of virtual tangles. This generalization naturally arises when considering the self-crossings of the tangle. We prove that the generalization…

Geometric Topology · Mathematics 2019-04-24 Nicolas Petit

Whitehead doubles provide a plethora of examples of knots that are topologically slice but not smoothly slice. We discuss the problem of the Whitehead double of the Figure 8 knot and survey commonly used techniques to obstructing sliceness.…

Geometric Topology · Mathematics 2024-10-29 Megan Fairchild

This paper investigates stable cohomotopy groups in codimensions two and three from complementary algebraic and geometric viewpoints. For general CW complexes, we give a complete characterization of stable cohomotopy in codimension two and…

Algebraic Topology · Mathematics 2026-05-14 Pengcheng Li , Jianzhong Pan , Jie Wu

We introduce an algebraic structure we call semiquandles whose axioms are derived from flat Reidemeister moves. Finite semiquandles have associated counting invariants and enhanced invariants defined for flat virtual knots and links. We…

Geometric Topology · Mathematics 2011-09-20 Allison Henrich , Sam Nelson

We discuss the theory of knots, and describe how knot invariants arise naturally in gravitational physics. The focus of this review is to delineate the relationship between knot theory and the loop representation of non-perturbative…

High Energy Physics - Theory · Physics 2008-11-26 Tomas Liko , Louis H. Kauffman

We compute lower bounds on the virtual crossing number and minimal surface genus of virtual knot diagrams from the arrow polynomial. In particular, we focus on several interesting examples.

Geometric Topology · Mathematics 2009-04-10 Kumud Bhandari , H. A. Dye , Louis H. Kauffman

Virtual index cocycle is the 1-cochain that counts virtual crossings in the arcs of a virtual link diagram. We show how this cocycle can be used to reformulate and unify some known invariants of virtual links.

Geometric Topology · Mathematics 2020-11-03 Igor Nikonov

We consider knot theories possessing a {\em parity}: each crossing is decreed {\em odd} or {\em even} according to some universal rule. If this rule satisfies some simple axioms concerning the behaviour under Reidemeister moves, this leads…

Geometric Topology · Mathematics 2009-12-31 Vassily Olegovich Manturov

Joyce has shown that the fundamental quandle of a classical knot can be derived from consideration of the fundamental group and the peripheral structure of the knot, and also that the group and much of the peripheral structure can be…

Geometric Topology · Mathematics 2009-05-26 Blake Winter