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Related papers: Crosscap numbers of 2-bridge knots

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An $n$-plat 1-knot is one isotopic to the plat closure of some $2n$-braid, which is also called an $n$-bridge 1-knot. Schubert classified 2-bridge 1-knots by considering their double branched covers which are homeomorphic to lens spaces. A…

Geometric Topology · Mathematics 2026-05-05 Jumpei Yasuda

The non-orientable 4-genus of a knot K in the three sphere is defined to be the minimum first Betti number of a non-orientable surface F in the four-ball so that K bounds F. We will survey the tools used to compute the non-orientable…

Geometric Topology · Mathematics 2024-03-05 Megan Fairchild

We show that a torus knot which is not 2-bridge has a unique irreducible bridge splitting of positive genus.

Geometric Topology · Mathematics 2015-05-27 Alexander Zupan

We introduce bridge trisections of knotted surfaces in the four-sphere. This description is inspired by the work of Gay and Kirby on trisections of four-manifolds and extends the classical concept of bridge splittings of links in the…

Geometric Topology · Mathematics 2017-08-10 Jeffrey Meier , Alexander Zupan

We determine the rational Khovanov bigraded homology groups of all Kanenobu knots. Also, we determine the crossing number for all Kanenobu knots $K(p,q)$ with $pq > 0$ or $|pq|\leq \max \{|p|, |q|\}$. In the case where $pq < 0$ and $|pq| >…

Geometric Topology · Mathematics 2014-05-06 Khaled Qazaqzeh , Isra Mansour

We publish a table of primitive finite-type invariants of order less than or equal to six, for knots of ten or fewer crossings. We note certain mod-2 congruences, one of which leads to a chirality criterion in the Alexander polynomial. We…

Geometric Topology · Mathematics 2007-05-23 Ted Stanford

We determine the crossing number of polynomial size curve systems on standard surfaces, in terms of the genus, up to high precision.

Geometric Topology · Mathematics 2026-01-29 Sebastian Baader , Jasmin Jörg , Hugo Parlier

The splitting number of a link is the minimal number of crossing changes between different components required to convert it into a split link. We obtain a lower bound on the splitting number in terms of the (multivariable) signature and…

Geometric Topology · Mathematics 2016-10-27 David Cimasoni , Anthony Conway , Kleopatra Zacharova

The ropelength of a knot is the minimum length required to tie it. Computational upper bounds have previously been computed for every prime knot with up to 11 crossings. Here, we present ropelength measurements for the 2176 knots with 12…

Geometric Topology · Mathematics 2023-06-01 Alexander R. Klotz , Caleb J. Anderson

A knot is called minimal if its knot group admits epimorphisms onto the knot groups of only the trivial knot and itself. In this paper, we determine which two-bridge knot $\mathfrak{b}(p,q)$ is minimal where $q \leq 6$ or $p \leq 100$.

Geometric Topology · Mathematics 2016-09-09 Fumikazu Nagasato , Masaaki Suzuki , Anh T. Tran

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

Roberts proved that a family of alternating, arborescent, prime knots each have at least $2^{2n-1}$ distinct minimal genus Seifert surfaces, where $n$ is the genus of the knot in question. We give a subfamily of these knots that have…

Geometric Topology · Mathematics 2013-10-30 Jessica E. Banks

We introduce the warping crossing polynomial of an oriented knot diagram by using the warping degrees of crossing points of the diagram. Given a closed transversely intersected plane curve, we consider oriented knot diagrams obtained from…

Geometric Topology · Mathematics 2011-12-20 Akio Kawauchi , Ayaka Shimizu

We will strengthen the known upper and lower bounds on the delta-crossing number of knots in therms of the triple-crossing number. The latter bound turns out to be strong enough to obtain (unknown values of) triple-crossing numbers for a…

Geometric Topology · Mathematics 2023-03-06 Michal Jablonowski

The concordance genus of a knot is the least genus of any knot in its concordance class. It is bounded above by the genus of the knot, and bounded below by the slice genus, two well-studied invariants. In this paper we consider the…

Geometric Topology · Mathematics 2015-03-20 M. Kate Kearney

Understanding ideal points in the character varieties of knot complements has led to a number of important invariants for 3-manifolds. Ohtsuki (1994) counted the ideal points for character varieties of 2-bridge knot complements, and he made…

Geometric Topology · Mathematics 2026-05-22 Cynthia L. Curtis , Kendra Ebke , Kate O'Connor

A multi-crossing (or n-crossing) is a singular point in a projection at which n strands cross so that each strand bisects the crossing. We generalize the classic result of Kauffman, Murasugi, and Thistlethwaite, which gives the upper bound…

In this paper we compute the sharp lower bounds for the crossing number of $n$-string $k$-loop essential tangles. For essential tangles with only string components, we characterise the ones with the minimum crossing number for a given…

Geometric Topology · Mathematics 2017-08-30 João Miguel Nogueira , António Salgueiro

In this article we study a partial ordering on knots in the 3-sphere where K_1 is greater than or equal to K_2 if there is an epimorphism from the knot group of K_1 onto the knot group of K_2 which preserves peripheral structure. If K_1 is…

Geometric Topology · Mathematics 2014-10-01 Jim Hoste , Patrick D. Shanahan

We present an atlas of Legendrian knots in standard contact three-space. This gives a conjectural Legendrian classification for all knots with arc index at most 9, including alternating knots through 7 crossings and nonalternating knots…

Symplectic Geometry · Mathematics 2013-05-08 Wutichai Chongchitmate , Lenhard Ng