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Related papers: Signed clasp numbers and four-genus bounds

200 papers

We provide the optimal linear bound for the signature of positive four-braids in terms of the three-genus of their closures. As a consequence, we improve previously known linear bounds for the signature in terms of the first Betti number…

Geometric Topology · Mathematics 2018-06-15 Peter Feller

We investigate the nonorientable 4-genus $\gamma_4$ of a special family of 2-bridge knots, the twist knots and double twist knots $C(m,n)$. Because the nonorientable 4-genus is bounded by the nonorientable 3-genus, it is known that…

Geometric Topology · Mathematics 2023-03-30 Jim Hoste , Patrick D. Shanahan , Cornelia A. Van Cott

Let K be a knot in the 3-sphere with 2-fold branched covering space M. If for some prime p congruent to 3 mod 4 the p-torsion in the first homology of M is cyclic with odd exponent, then K is of infinite order in the knot concordance group.…

Geometric Topology · Mathematics 2007-07-24 Charles Livingston , Swatee Naik

We study the four-genus of linear combinations of torus knots: aT(p,q) # -bT(p',q'). Fixing positive p, q, p', and q', our focus is on the behavior of the four-genus as a function of positive a and b. Three types of examples are presented:…

Geometric Topology · Mathematics 2018-06-20 Charles Livingston , Cornelia A. Van Cott

We prove that 0 is a characterizing slope for infinitely many knots, namely the genus-1 knots whose knot Floer homology is 2-dimensional in the top Alexander grading, which we classified in recent work and which include all $(-3,3,2n+1)$…

Geometric Topology · Mathematics 2025-02-11 John A. Baldwin , Steven Sivek

We show that a positive braid knot has maximal topological 4-genus exactly if it has maximal signature invariant. As an application, we determine all positive braid knots with maximal topological 4-genus and compute the topological 4-genus…

Geometric Topology · Mathematics 2017-12-01 Livio Liechti

The first and last named authors have demonstrated the existence of knots for which every integral slope is non-characterizing. In this short note, we extend this result in two ways. There exists a knot that shares for every integer n the…

Geometric Topology · Mathematics 2025-12-16 Kenneth L. Baker , Marc Kegel , Kimihiko Motegi

Weaving knots are alternating knots with the same projection as torus knots, and were conjectured by X.-S. Lin to be among the maximum volume knots for fixed crossing number. We provide the first asymptotically correct volume bounds for…

Geometric Topology · Mathematics 2016-12-21 Abhijit Champanerkar , Ilya Kofman , Jessica S. Purcell

We construct an infinite collection of knots with the property that any knot in this family has $n$-string essential tangle decompositions for arbitrarily high $n$.

Geometric Topology · Mathematics 2017-05-19 João Miguel Nogueira

The 3-dimensional clasp number $cl(K)$ of a knot $K$ is the minimum number of clasp singularities of clasp disk, a singular immersed disk bounding $K$ whose singular set consists of only clasp singularities. We give a classification of…

Geometric Topology · Mathematics 2026-02-13 Tetsuya Ito

Using the techniques on annulus twists, we observe that $6_3$ has infinitely many non-characterizing slopes, which affirmatively answers a question by Baker and Motegi. Furthermore, we prove that the knots $6_2$, $6_3$, $7_6$, $7_7$, $8_1$,…

Geometric Topology · Mathematics 2021-03-09 Tetsuya Abe , Keiji Tagami

Hyperfinite knots, or limits of equivalence classes of knots induced by a knot invariant taking values in a metric space, were introduced in a previous article by the author. In this article, we present new examples of hyperfinite knots…

Geometric Topology · Mathematics 2009-11-13 Pedro Lopes

We introduce a new combinatorial method to encode knots and links with applications to knot invariants. Clasp diagrams defined in this paper are combinatorial blueprints for building knot diagrams out of full twists on two strings rather…

Geometric Topology · Mathematics 2019-11-11 Jacob Mostovoy , Michael Polyak

In the 1980's Daryl Cooper introduced the notion of a C-complex (or clasp-complex) bounded by a link and explained how to compute signatures and polynomial invariants using a C-complex. Since then this was extended by works of Cimasoni,…

Geometric Topology · Mathematics 2019-07-30 Jonah Amundsen , Eric Anderson , Christopher William Davis , Daniel Guyer

An open question asks if every knot of 4-genus g_s can be changed into a slice knot by g_s crossing changes. A counterexample is given.

Geometric Topology · Mathematics 2014-10-01 Charles Livingston

The stable 4-genus of a knot K in 3-space is the limiting value of g_4(nK)/n, where g_4 denotes the 4-genus and n goes to infinity. This induces a seminorm on CQ, the concordance group tensored with the rational numbers. Basic properties of…

Geometric Topology · Mathematics 2015-03-13 Charles Livingston

We describe a procedure for creating infinite families of knots, each having the maximum degree of their HOMFLY polynomial strictly less than twice their canonical genus. These families build upon examples first found by Stoimenow.

Geometric Topology · Mathematics 2007-05-23 Mark Brittenham , Jacqueline Jensen

The slicing number of a knot, $u_s(K)$, is the minimum number of crossing changes required to convert $K$ to a slice knot. This invariant is bounded above by the unknotting number and below by the slice genus $g_s(K)$. We show that for many…

Geometric Topology · Mathematics 2008-02-18 Brendan Owens

Many well studied knots can be realized as positive braid knots where the braid word contains a positive full twist; we say that such knots are twist positive. Some important families of knots are twist positive, including torus knots,…

Geometric Topology · Mathematics 2025-01-08 Siddhi Krishna , Hugh Morton

We classify knot traces with trisection genus at most 2. We give infinitely many knots whose traces have trisection genus 3, and infinitely many knots whose traces have trisection genus 4. We also show that there exist infinite families of…

Geometric Topology · Mathematics 2026-05-29 Natsuya Takahashi