Finite Type (Vassiliev) Invariants: Difference between revisions

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K = Knot[10, k] ; v2 = Vassiliev[2][K]; v3 = Vassiliev[3][K];
{{v2, v3}, {v2, -v3}},
{k, 165}
],
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Revision as of 23:04, 28 August 2005


(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):