Cabling: Difference between revisions

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{{Startup Note}}
{{Startup Note}}
<!--$$Import["http://katlas.org/wiki/CableComponent.m&action=raw"];$$-->
<!--$$Import["http://katlas.org/wiki/CableComponent.m&action=raw"];$$--><!--END-->
<!--$$CableComponent[BR[3, {1, 2}], Knot[3, 1]] // DrawMorseLink$$-->
<!--$$CableComponent[BR[3, {1, 2}], Knot[3, 1]] // DrawMorseLink$$-->
<!--Robot Land, no human edits to "END"-->
<!--Robot Land, no human edits to "END"-->

Revision as of 18:29, 18 November 2007


CableComponent[BR[n,js],K], whose code is available here, returns the -th cable of the knot with the braid on strands with crossings js = {j1, j2, ...} inserted in it. It also performs the necessary number of -twists on the components of the cable to compensate for a non-zero writhe number of the original knot. Cabling knot 3_1, for instance, and inserting the braid BR[3,{1,2}], we get:

(For In[1] see Setup)

In[3]:= CableComponent[BR[3, {1, 2}], Knot[3, 1]] // DrawMorseLink
Cabling Out 3.gif
Out[3]= -Graphics-

For some special cases, we can check our result using Burau's Theorem.