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A proof of Tait’s Conjecture on prime alternating - achiral knots

Nicola Ermotti, Cam Van Quach Hongler, Claude Weber (2012)

Annales de la faculté des sciences de Toulouse Mathématiques

In this paper we are interested in symmetries of alternating knots, more precisely in those related to achirality. We call the following statement Tait’s Conjecture on alternating - achiral knots:Let K be a prime alternating - achiral knot. Then there exists a minimal projection Π of K in S 2 S 3 and an involution ϕ : S 3 S 3 such that:1) ϕ reverses the orientation of S 3 ;2) ϕ ( S 2 ) = S 2 ;3) ϕ ( Π ) = Π ;4) ϕ has two fixed points on Π and hence reverses the orientation of K .The purpose of this paper is to prove this statement.For the historical...

A relationship between the non-acyclic Reidemeister torsion and a zero of the acyclic Reidemeister torsion

Yoshikazu Yamaguchi (2008)

Annales de l’institut Fourier

We show a relationship between the non-acyclic Reidemeister torsion and a zero of the acyclic Reidemeister torsion for a λ -regular SU ( 2 ) or SL ( 2 , ) -representation of a knot group. Then we give a method to calculate the non-acyclic Reidemeister torsion of a knot exterior. We calculate a new example and investigate the behavior of the non-acyclic Reidemeister torsion associated to a 2 -bridge knot and SU ( 2 ) -representations of its knot group.

A self-linking invariant of virtual knots

Louis H. Kauffman (2004)

Fundamenta Mathematicae

This paper introduces a self-linking invariant for virtual knots and links, and relates this invariant to a state model called the binary bracket, and to a class of coloring problems for knots and links that include classical coloring problems for cubic graphs.

A short proof of Eilenberg and Moore’s theorem

Maria Nogin (2007)

Open Mathematics

In this paper we give a short and simple proof the following theorem of S. Eilenberg and J.C. Moore: the only injective object in the category of groups is the trivial group.

A topological model of site-specific recombination that predicts the knot and link type of DNA products

Karin Valencia (2014)

Banach Center Publications

This is a short summary of a topological model of site-specific recombination, a cellular reaction that creates knots and links out of circular double stranded DNA molecules. The model is used to predict and characterise the topology of the products of a reaction on double stranded DNA twist knots. It is shown that all such products fall into a small family of Montesinos knots and links, meaning that the knot and link type of possible products is significantly reduced, thus aiding their experimental...

A topological version of Bertini's theorem

Artur Piękosz (1995)

Annales Polonici Mathematici

We give a topological version of a Bertini type theorem due to Abhyankar. A new definition of a branched covering is given. If the restriction π V : V Y of the natural projection π: Y × Z → Y to a closed set V ⊂ Y × Z is a branched covering then, under certain assumptions, we can obtain generators of the fundamental group π₁((Y×Z).

Currently displaying 81 – 100 of 196