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Related papers: Crosscap numbers of 2-bridge knots

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We present the complete classification of the subgroup of the classical knot concordance group generated by knots with eight or fewer crossings. Proofs are presented in summary. We also describe extensions of this work to the case of nine…

Geometric Topology · Mathematics 2020-09-01 Julia Collins , Paul Kirk , Charles Livingston

For some families of two-bridge knots, including double-twist knots with genus at least four, we determine precisely the set of integers $n>1$ such that the fundamental group of the $n$-fold cyclic branched cover of the 3-sphere along these…

Geometric Topology · Mathematics 2020-02-26 Hannah Turner

Determining unknotting numbers is a large and widely studied problem. We consider the more general question of the unknotting number of a spatial graph. We show the unknotting number of spatial graphs is subadditive. Let $g$ be an embedding…

Geometric Topology · Mathematics 2018-05-03 Dorothy Buck , Danielle O'Donnol

It is known that there are only finitely many knots with super bridge index 3. Jin and Jeon have provided a list of possible such candidates. However, they conjectured that the only knots with super bridge index 3 are trefoil and the figure…

Geometric Topology · Mathematics 2012-09-17 Rama Mishra

We derive new obstructions to periodicity of classical knots by employing the Heegaard Floer correction terms of the finite cyclic branched covers of the knots. Applying our results to two fold covers, we demonstrate through numerous…

Geometric Topology · Mathematics 2014-09-23 Stanislav Jabuka , Swatee Naik

We are giving tables of quasi-alternating knots with $8\le n \le 12$ crossings. As the obstructions for a knot to be quasialternating we used homology thickness with regards to Khovanov homology, odd homology, and Heegaard-Floer homology…

Geometric Topology · Mathematics 2014-04-23 Slavik Jablan

We classify all knot diagrams of genus two and three, and give applications to positive, alternating and homogeneous knots, including a classification of achiral genus 2 alternating knots, slice or achiral 2-almost positive knots, a proof…

Geometric Topology · Mathematics 2008-08-30 A. Stoimenow

We compose the table of knots in the thickened torus T x I having diagrams with at most 4 crossings. The knots are constructed by the three-step process. First we list regular graphs of degree 4 with at most 4 vertices, then for each graph…

Geometric Topology · Mathematics 2012-07-02 A. A. Akimova , S. V. Matveev

By examining knot Floer homology, we extend a result of Ozsv\'ath and Stipsicz and show further infinitely many Legendrian and transversely non-simple knot types among two-bridge knots. We give sufficient conditions of Legendrian and…

Symplectic Geometry · Mathematics 2020-04-03 Viktória Földvári

A knot in the three-sphere is doubly slice if it is the cross-section of an unknotted two-sphere in the four-sphere. For low-crossing knots, the most complete work to date gives a classification of doubly slice knots through 9 crossings. We…

Geometric Topology · Mathematics 2016-10-19 Charles Livingston , Jeffrey Meier

We describe a method of encoding various types of link diagrams, including those with classical, flat, rigid, welded, and virtual crossings. We show that this method may be used to encode link diagrams, up to equivalence, in a notation…

Geometric Topology · Mathematics 2013-05-03 Chad Musick

The warping degree of an oriented knot diagram is the minimal number of crossing changes which are required to obtain a monotone knot diagram from the diagram. The minimal warping degree of a knot is the minimal value of the warping degree…

Geometric Topology · Mathematics 2020-05-01 Ayaka Shimizu

We consider closed acylindrical surfaces in 3-manifolds and in knot and link complements, and show that the genus of these surfaces is bounded linearly by the number of tetrahedra in the triangulation of the manifold and by the number of…

Geometric Topology · Mathematics 2009-09-29 Mario Eudave-Munoz , Max Neumann-Coto

Connected sum and trivalent vertex sum are natural operations on genus 2 spatial graphs and, as with knots, tunnel number behaves in interesting ways under these operations. We prove sharp Scharlemann-Schultens type bounds for the tunnel…

Geometric Topology · Mathematics 2021-11-10 Scott A. Taylor , Maggy Tomova

Our goal is to systematically compute the $\mathbb{C}P^2$-genus of all prime knots up to 8-crossings. We obtain upper bounds on the $\mathbb{C}P^2$-genus via coherent band surgery. We obtain lower bounds by obstructing homological degrees…

Geometric Topology · Mathematics 2019-12-05 Jacob Pichelmeyer

Let c(K;F) denote the surface crossing number of a knot K with respect to a closed connected surface F in S^3. We relate c(K;F) to the tunnel number t(K) and to the Heegaard deficiency delta(F)=g(M_1;F)+g(M_2;F)-g(F), where S^3=M_1 union_F…

Geometric Topology · Mathematics 2026-05-22 Makoto Ozawa

We consider diagrams of links in $S^2$ obtained by projection from $S^3$ with the Hopf map and the minimal crossing number for such diagrams. Knots admitting diagrams with at most one crossing are classified. Some properties of these knots…

Geometric Topology · Mathematics 2020-06-25 Maciej Mroczkowski

The twisting number of a ribbon knot $K$ is the minimal number of tangle replacements on the symmetry axis of $J \# -J$ for any knot $J$ that is required to produce a symmetric union diagram of $K$. We prove that the twisting number is…

Geometric Topology · Mathematics 2024-06-24 Vitalijs Brejevs , Peter Feller

We consider a relation between two kinds of unknotting numbers defined by using a band surgery on unoriented knots; the band-unknotting number and H(2)-unknotting number, which we may characterize in terms of the first Betti number of…

Geometric Topology · Mathematics 2011-12-13 Tetsuya Abe , Taizo Kanenobu

We prove that the knot groups of $6_2$ and $7_6$ are not bi-orderable. These are the only two knot groups up to 7 crossings whose bi-orderability was not known. Our method applies to a very broad class of knots.

Group Theory · Mathematics 2017-06-14 Azer Akhmedov , Cody Martin