Finite Type (Vassiliev) Invariants

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(For In[1] see Setup)

In[1]:= ?Vassiliev

Vassiliev[2][K] computes the (standardly normalized) type 2 Vassiliev invariant of the knot K, i.e., the coefficient of z^2 in Conway[K][z]. Vassiliev[3][K] computes the (standardly normalized) type 3 Vassiliev invariant of the knot K, i.e., 3J(1)-(1/36)J'(1) where J is the Jones polynomial of K.

Thus, for example, let us reproduce Willerton's "fish" (arXiv:math.GT/0104061), the result of plotting the values of against the values of , where is the (standardly normalized) type 2 invariant of , is the (standardly normalized) type 3 invariant of , and where runs over a set of knots with equal crossing numbers (10, in the example below):

In[2]:=

Show[ot[

 Join @@ Table[
   K = Knot[10, k] ; v2 = Vassiliev[2][K]; v3 = Vassiliev[3][K];
   {{v2, v3}, {v2, -v3}},
   {k, 165}
 ],
 PlotStyle -> PointSize[0.02], PlotRange -> All, AspectRatio -> 1]
File:Finite Type (Vassiliev) Invariants Out 2.gif
Out[2]= -Graphics-