00 2 On the writhe of non - closed curves Preprint
نویسنده
چکیده
The writhe of a space curve fragment is considered for various boundary conditions. An expression for the writhe as a function of arclength for an arbitrary space curve is obtained. The formula is built on the base of closing the tangent indicatrix with a geodesic. The corresponding closure of a curve in 3-space is explicitly constructed. The addition rule for writhe is formulated. A relationship connecting the writhe with the Gauß integral over the open curve is presented. The single and double regular helical shapes are examined as examples.
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