Unsolved Problems in Virtual Knot Theory and Combinatorial Knot Theory
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Finite Type Invariants for Knots 3-Manifolds
Pergamon Topology Vol. 37, No. 3. PP. 673-707, 1998 ~2 1997 Elsevier Science Ltd Printed in Great Britain. All rights reserved 0040-9383/97519.00 + 0.00 PII: soo4o-9383(97)00034-7 FINITE TYPE INVARIANTS FOR KNOTS IN 3-MANIFOLDS EFSTRATIA KALFAGIANNI + (Received 5 November 1993; in revised form 4 October 1995; final version 16 February 1997) We use the Jaco-Shalen and Johannson theory of the characteristic submanifold and the Torus theorem (Gabai, Casson-Jungreis)_ to develop an intrinsic finite tvne__ theory for knots in irreducible 3-manifolds. We also establish a relation between finite type knot invariants in 3-manifolds and these in R3. As an application we obtain the existence of non-trivial finite type invariants for knots in irreducible 3-manifolds. 0 1997 Elsevier Science Ltd. All rights reserved 0. INTRODUCTION The theory of quantum groups gives a systematic way of producing families of polynomial invariants, for knots and links in [w3 or S3 (see for example [18,24]). In particular, the Jones polynomial [12] and its generalizations [6,13], can be obtained that way. All these Jones-type invariants are defined as state models on a knot diagram or as traces of a braid group representation. On the other hand Vassiliev [25,26], introduced vast families of numerical knot invariants (Jinite type invariants), by studying the topology of the space of knots in [w3. The compu- tation of these invariants, involves in an essential way the computation of related invariants for special knotted graphs (singular knots). It is known [l-3], that after a suitable change of variable the coefficients of the power series expansions of the Jones-type invariants, are of Jinite type. -
Finite Type Invariants of W-Knotted Objects Iii: the Double Tree Construction
FINITE TYPE INVARIANTS OF W-KNOTTED OBJECTS III: THE DOUBLE TREE CONSTRUCTION DROR BAR-NATAN AND ZSUZSANNA DANCSO Abstract. This is the third in a series of papers studying the finite type invariants of various w-knotted objects and their relationship to the Kashiwara-Vergne problem and Drinfel’d associators. In this paper we present a topological solution to the Kashiwara- Vergne problem.AlekseevEnriquezTorossian:ExplicitSolutions In particular we recover via a topological argument the Alkeseev-Enriquez- Torossian [AET] formula for explicit solutions of the Kashiwara-Vergne equations in terms of associators. We study a class of w-knotted objects: knottings of 2-dimensional foams and various associated features in four-dimensioanl space. We use a topological construction which we name the double tree construction to show that every expansion (also known as universal fi- nite type invariant) of parenthesized braids extends first to an expansion of knotted trivalent graphs (a well known result), and then extends uniquely to an expansion of the w-knotted objects mentioned above. In algebraic language, an expansion for parenthesized braids is the same as a Drin- fel’d associator Φ, and an expansion for the aforementionedKashiwaraVergne:Conjecture w-knotted objects is the same as a solutionAlekseevTorossian:KashiwaraVergneV of the Kashiwara-Vergne problem [KV] as reformulated by AlekseevAlekseevEnriquezTorossian:E and Torossian [AT]. Hence our result provides a topological framework for the result of [AET] that “there is a formula for V in terms of Φ”, along with an independent topological proof that the said formula works — namely that the equations satisfied by V follow from the equations satisfied by Φ. -
Coefficients of Homfly Polynomial and Kauffman Polynomial Are Not Finite Type Invariants
COEFFICIENTS OF HOMFLY POLYNOMIAL AND KAUFFMAN POLYNOMIAL ARE NOT FINITE TYPE INVARIANTS GYO TAEK JIN AND JUNG HOON LEE Abstract. We show that the integer-valued knot invariants appearing as the nontrivial coe±cients of the HOMFLY polynomial, the Kau®man polynomial and the Q-polynomial are not of ¯nite type. 1. Introduction A numerical knot invariant V can be extended to have values on singular knots via the recurrence relation V (K£) = V (K+) ¡ V (K¡) where K£, K+ and K¡ are singular knots which are identical outside a small ball in which they di®er as shown in Figure 1. V is said to be of ¯nite type or a ¯nite type invariant if there is an integer m such that V vanishes for all singular knots with more than m singular double points. If m is the smallest such integer, V is said to be an invariant of order m. q - - - ¡@- @- ¡- K£ K+ K¡ Figure 1 As the following proposition states, every nontrivial coe±cient of the Alexander- Conway polynomial is a ¯nite type invariant [1, 6]. Theorem 1 (Bar-Natan). Let K be a knot and let 2 4 2m rK (z) = 1 + a2(K)z + a4(K)z + ¢ ¢ ¢ + a2m(K)z + ¢ ¢ ¢ be the Alexander-Conway polynomial of K. Then a2m is a ¯nite type invariant of order 2m for any positive integer m. The coe±cients of the Taylor expansion of any quantum polynomial invariant of knots after a suitable change of variable are all ¯nite type invariants [2]. For the Jones polynomial we have Date: October 17, 2000 (561). -
On Finite Type 3-Manifold Invariants Iii: Manifold Weight Systems
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector Pergamon Top&y?. Vol. 37, No. 2, PP. 221.243, 1998 ~2 1997 Elsevw Science Ltd Printed in Great Britain. All rights reserved 0040-9383/97 $19.00 + 0.00 PII: SOO40-9383(97)00028-l ON FINITE TYPE 3-MANIFOLD INVARIANTS III: MANIFOLD WEIGHT SYSTEMS STAVROSGAROUFALIDIS and TOMOTADAOHTSUKI (Received for publication 9 June 1997) The present paper is a continuation of [11,6] devoted to the study of finite type invariants of integral homology 3-spheres. We introduce the notion of manifold weight systems, and show that type m invariants of integral homology 3-spheres are determined (modulo invariants of type m - 1) by their associated manifold weight systems. In particular, we deduce a vanishing theorem for finite type invariants. We show that the space of manifold weight systems forms a commutative, co-commutative Hopf algebra and that the map from finite type invariants to manifold weight systems is an algebra map. We conclude with better bounds for the graded space of finite type invariants of integral homology 3-spheres. 0 1997 Elsevier Science Ltd. All rights reserved 1. INTRODUCTION 1.1. History The present paper is a continuation of [ll, 63 devoted to the study of finite type invariants of oriented integral homology 3-spheres. There are two main sources of motivation for the present work: (perturbative) Chern-Simons theory in three dimensions, and Vassiliev invariants of knots in S3. Witten [16] in his seminal paper, using path integrals (an infinite dimensional “integra- tion” method) introduced a topological quantum field theory in three dimensions whose Lagrangian was the Chern-Simons function on the space of all connections. -
Introduction to Vassiliev Knot Invariants First Draft. Comments
Introduction to Vassiliev Knot Invariants First draft. Comments welcome. July 20, 2010 S. Chmutov S. Duzhin J. Mostovoy The Ohio State University, Mansfield Campus, 1680 Univer- sity Drive, Mansfield, OH 44906, USA E-mail address: [email protected] Steklov Institute of Mathematics, St. Petersburg Division, Fontanka 27, St. Petersburg, 191011, Russia E-mail address: [email protected] Departamento de Matematicas,´ CINVESTAV, Apartado Postal 14-740, C.P. 07000 Mexico,´ D.F. Mexico E-mail address: [email protected] Contents Preface 8 Part 1. Fundamentals Chapter 1. Knots and their relatives 15 1.1. Definitions and examples 15 § 1.2. Isotopy 16 § 1.3. Plane knot diagrams 19 § 1.4. Inverses and mirror images 21 § 1.5. Knot tables 23 § 1.6. Algebra of knots 25 § 1.7. Tangles, string links and braids 25 § 1.8. Variations 30 § Exercises 34 Chapter 2. Knot invariants 39 2.1. Definition and first examples 39 § 2.2. Linking number 40 § 2.3. Conway polynomial 43 § 2.4. Jones polynomial 45 § 2.5. Algebra of knot invariants 47 § 2.6. Quantum invariants 47 § 2.7. Two-variable link polynomials 55 § Exercises 62 3 4 Contents Chapter 3. Finite type invariants 69 3.1. Definition of Vassiliev invariants 69 § 3.2. Algebra of Vassiliev invariants 72 § 3.3. Vassiliev invariants of degrees 0, 1 and 2 76 § 3.4. Chord diagrams 78 § 3.5. Invariants of framed knots 80 § 3.6. Classical knot polynomials as Vassiliev invariants 82 § 3.7. Actuality tables 88 § 3.8. Vassiliev invariants of tangles 91 § Exercises 93 Chapter 4. -
Electricity Demand Evolution Driven by Storm Motivated Population
aphy & N r at og u e ra G l Allen et al., J Geogr Nat Disast 2014, 4:2 f D o i s l a Journal of a s DOI: 10.4172/2167-0587.1000126 n t r e u r s o J ISSN: 2167-0587 Geography & Natural Disasters ResearchResearch Article Article OpenOpen Access Access Electricity Demand Evolution Driven by Storm Motivated Population Movement Melissa R Allen1,2, Steven J Fernandez1,2*, Joshua S Fu1,2 and Kimberly A Walker3 1University of Tennessee, Knoxville, Oak Ridge, USA 2Oak Ridge National Laboratory, Oak Ridge, USA 3Indiana University, Oak Ridge, USA Abstract Managing the risks to reliable delivery of energy to vulnerable populations posed by local effects of climate change on energy production and delivery is a challenge for communities worldwide. Climate effects such as sea level rise, increased frequency and intensity of natural disasters, force populations to move locations. These moves result in changing geographic patterns of demand for infrastructure services. Thus, infrastructures will evolve to accommodate new load centers while some parts of the network are underused, and these changes will create emerging vulnerabilities. Forecasting the location of these vulnerabilities by combining climate predictions and agent based population movement models shows promise for defining these future population distributions and changes in coastal infrastructure configurations. In this work, we created a prototype agent based population distribution model and developed a methodology to establish utility functions that provide insight about new infrastructure vulnerabilities that might result from these new electric power topologies. Combining climate and weather data, engineering algorithms and social theory, we use the new Department of Energy (DOE) Connected Infrastructure Dynamics Models (CIDM) to examine electricity demand response to increased temperatures, population relocation in response to extreme cyclonic events, consequent net population changes and new regional patterns in electricity demand. -
Some Remarks on the Chord Index
Some remarks on the chord index Hongzhu Gao A joint work with Prof. Zhiyun Cheng and Dr. Mengjian Xu Beijing Normal University Novosibirsk State University June 17-21, 2019 1 / 54 Content 1. A brief review on virtual knot theory 2. Two virtual knot invariants derived from the chord index 3. From the viewpoint of finite type invariant 4. Flat virtual knot invariants 2 / 54 A brief review on virtual knot theory Classical knot theory: Knot types=fknot diagramsg/fReidemeister movesg Ω1 Ω2 Ω3 Figure 1: Reidemeister moves Virtual knot theory: Besides over crossing and under crossing, we add another structure to a crossing point: virtual crossing virtual crossing b Figure 2: virtual crossing 3 / 54 A brief review on virtual knot theory Virtual knot types= fall virtual knot diagramsg/fgeneralized Reidemeister movesg Ω1 Ω2 Ω3 Ω10 Ω20 Ω30 s Ω3 Figure 3: generalized Reidemeister moves 4 / 54 A brief review on virtual knot theory Flat virtual knots (or virtual strings by Turaev) can be regarded as virtual knots without over/undercrossing information. More precisely, a flat virtual knot diagram can be obtained from a virtual knot diagram by replacing all real crossing points with flat crossing points. By replacing all real crossing points with flat crossing points in Figure 3 one obtains the flat generalized Reidemeister moves. Then Flat virtual knot types= fall flat virtual knot diagramsg/fflat generalized Reidemeister movesg 5 / 54 A brief review on virtual knot theory Virtual knot theory was introduced by L. Kauffman. Roughly speaking, there are two motivations to extend the classical knot theory to virtual knot theory. -
A Note on Jones Polynomial and Cosmetic Surgery
\3-Wu" | 2019/10/30 | 23:55 | page 1087 | #1 Communications in Analysis and Geometry Volume 27, Number 5, 1087{1104, 2019 A note on Jones polynomial and cosmetic surgery Kazuhiro Ichihara and Zhongtao Wu We show that two Dehn surgeries on a knot K never yield mani- 00 folds that are homeomorphic as oriented manifolds if VK (1) = 0 or 000 6 VK (1) = 0. As an application, we verify the cosmetic surgery con- jecture6 for all knots with no more than 11 crossings except for three 10-crossing knots and five 11-crossing knots. We also compute the finite type invariant of order 3 for two-bridge knots and Whitehead doubles, from which we prove several nonexistence results of purely cosmetic surgery. 1. Introduction Dehn surgery is an operation to modify a three-manifold by drilling and then regluing a solid torus. Denote by Yr(K) the resulting three-manifold via Dehn surgery on a knot K in a closed orientable three-manifold Y along a slope r. Two Dehn surgeries along K with distinct slopes r and r0 are called equivalent if there exists an orientation-preserving homeomorphism of the complement of K taking one slope to the other, while they are called purely cosmetic if Yr(K) ∼= Yr0 (K) as oriented manifolds. In Gordon's 1990 ICM talk [6, Conjecture 6.1] and Kirby's Problem List [11, Problem 1.81 A], it is conjectured that two surgeries on inequivalent slopes are never purely cosmetic. We shall refer to this as the cosmetic surgery conjecture. In the present paper we study purely cosmetic surgeries along knots in 3 3 3 3 the three-sphere S . -
Section 10.2. New Polynomial Invariants
10.2. New Polynomial Invariants 1 Section 10.2. New Polynomial Invariants Note. In this section we mention the Jones polynomial and give a recursion for- mula for the HOMFLY polynomial. We give an example of the computation of a HOMFLY polynomial. Note. Vaughan F. R. Jones introduced a new knot polynomial in: A Polynomial Invariant for Knots via von Neumann Algebra, Bulletin of the American Mathe- matical Society, 12, 103–111 (1985). A copy is available online at the AMS.org website (accessed 4/11/2021). This is now known as the Jones polynomial. It is also a knot invariant and so can be used to potentially distinguish between knots. Shortly after the appearance of Jones’ paper, it was observed that the recursion techniques used to find the Jones polynomial and Conway polynomial can be gen- eralized to a 2-variable polynomial that contains information beyond that of the Jones and Conway polynomials. Note. The 2-variable polynomial was presented in: P. Freyd, D. Yetter, J. Hoste, W.B.R. Lickorish, and A. Ocneanu, A New Polynomial of Knots and Links, Bul- letin of the American Mathematical Society, 12(2): 239–246 (1985). This paper is also available online at the AMS.org website (accessed 4/11/2021). Based on a permutation of the first letters of the names of the authors, this has become knows as the “HOMFLY polynomial.” 10.2. New Polynomial Invariants 2 Definition. The HOMFLY polynomial, PL(`, m), is given by the recursion formula −1 `PL+ (`, m) + ` PL− (`, m) = −mPLS (`, m), and the condition PU (`, m) = 1 for U the unknot. -
Rotationally Symmetric Rose Links
Rose-Hulman Undergraduate Mathematics Journal Volume 14 Issue 1 Article 3 Rotationally Symmetric Rose Links Amelia Brown Simpson College, [email protected] Follow this and additional works at: https://scholar.rose-hulman.edu/rhumj Recommended Citation Brown, Amelia (2013) "Rotationally Symmetric Rose Links," Rose-Hulman Undergraduate Mathematics Journal: Vol. 14 : Iss. 1 , Article 3. Available at: https://scholar.rose-hulman.edu/rhumj/vol14/iss1/3 Rose- Hulman Undergraduate Mathematics Journal Rotationally Symmetric Rose Links Amelia Browna Volume 14, No. 1, Spring 2013 Sponsored by Rose-Hulman Institute of Technology Department of Mathematics Terre Haute, IN 47803 Email: [email protected] a http://www.rose-hulman.edu/mathjournal Simpson College Rose-Hulman Undergraduate Mathematics Journal Volume 14, No. 1, Spring 2013 Rotationally Symmetric Rose Links Amelia Brown Abstract. This paper is an introduction to rose links and some of their properties. We used a series of invariants to distinguish some rose links that are rotationally symmetric. We were able to distinguish all 3-component rose links and narrow the bounds on possible distinct 4 and 5-component rose links to between 2 and 8, and 2 and 16, respectively. An algorithm for drawing rose links and a table of rose links with up to five components are included. Acknowledgements: The initial cursory observations on rose links were made during the 2011 Dr. Albert H. and Greta A. Bryan Summer Research Program at Simpson College in conjunction with fellow students Michael Comer and Jes Toyne, with Dr. William Schellhorn serving as research advisor. The research presented in this paper, including developing the definitions and related concepts about rose links and applying invariants, was conducted as a part of the author's senior research project at Simpson College, again under the advisement of Dr. -
A Mathematical Analysis of Knotting and Linking in Leonardo Da Vinci's
November 3, 2014 Journal of Mathematics and the Arts Leonardov4 To appear in the Journal of Mathematics and the Arts Vol. 00, No. 00, Month 20XX, 1–31 A Mathematical Analysis of Knotting and Linking in Leonardo da Vinci’s Cartelle of the Accademia Vinciana Jessica Hoya and Kenneth C. Millettb Department of Mathematics, University of California, Santa Barbara, CA 93106, USA (submitted November 2014) Images of knotting and linking are found in many of the drawings and paintings of Leonardo da Vinci, but nowhere as powerfully as in the six engravings known as the cartelle of the Accademia Vinciana. We give a mathematical analysis of the complex characteristics of the knotting and linking found therein, the symmetry these structures embody, the application of topological measures to quantify some aspects of these configurations, a comparison of the complexity of each of the engravings, a discussion of the anomalies found in them, and a comparison with the forms of knotting and linking found in the engravings with those found in a number of Leonardo’s paintings. Keywords: Leonardo da Vinci; engravings; knotting; linking; geometry; symmetry; dihedral group; alternating link; Accademia Vinciana AMS Subject Classification:00A66;20F99;57M25;57M60 1. Introduction In addition to his roughly fifteen celebrated paintings and his many journals and notes of widely ranging explorations, Leonardo da Vinci is credited with the creation of six intricate designs representing entangled loops, for example Figure 1, in the 1490’s. Originally constructed as copperplate engravings, these designs were attributed to Leonardo and ‘known as the cartelle of the Accademia Vinciana’ [1]. -
Space-Efficient Knot Mosaics for Prime Knots with Mosaic Number 6
Space-Efficient Knot Mosaics for Prime Knots with Mosaic Number 6 Aaron Heap and Douglas Knowles October 18, 2018 Abstract In 2008, Kauffman and Lomonaco introduce the concepts of a knot mosaic and the mosaic number of a knot or link, the smallest integer n such that a knot or link K can be represented on an n-mosaic. In [2], the authors explore space-efficient knot mosaics and the tile number of a knot or link, the smallest number of non-blank tiles necessary to depict the knot or link on a mosaic. They determine bounds for the tile number in terms of the mosaic number. In this paper, we focus specifically on prime knots with mosaic number 6. We determine a complete list of these knots, provide a minimal, space-efficient knot mosaic for each of them, and determine the tile number (or minimal mosaic tile number) of each of them. 1 Introduction Mosaic knot theory was first introduced by Kauffman and Lomonaco in the paper Quantum Knots and Mosaics [6] and was later proven to be equivalent to tame knot theory by Kuriya and Shehab in the paper The Lomonaco-Kauffman Conjecture [4]. The idea of mosaic knot theory is to create a knot or link diagram on an n × n grid using mosaic tiles selected from the collection of eleven tiles shown in Figure 1. The knot or link projection is represented by arcs, line segments, or crossings drawn on each tile. These tiles are identified, respectively, as T0, T1, T2, :::, T10. Tile T0 is a blank tile, and we refer to the rest collectively as non-blank tiles.