Cabling: Difference between revisions
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{{Startup Note}} |
{{Startup Note}} |
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<!--$$Import["http://katlas.org/wiki/CableComponent.m&action=raw"];$$--> |
<!--$$Import["http://katlas.org/wiki/CableComponent.m&action=raw"];$$--><!--END--> |
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<!--$$CableComponent[BR[3, {1, 2}], Knot[3, 1]] // DrawMorseLink$$--> |
<!--$$CableComponent[BR[3, {1, 2}], Knot[3, 1]] // DrawMorseLink$$--> |
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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]:=
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CableComponent[BR[3, {1, 2}], Knot[3, 1]] // DrawMorseLink
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Out[3]=
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-Graphics-
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For some special cases, we can check our result using Burau's Theorem.