Feldman's Theorem
FeldmansTheorem
Any nondegenerate closed space curve may be nondegenerately deformed into either of the two curves illustrated above. Neither of these can be nondegenerately transformed into the other.
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References
Feldman, E. A. "Deformations of Closed Space Curves." J. Diff. Geom. 2, 67-75, 1968.Pohl, W. F. "The Self-Linking Number of a Closed Space Curve." J. Math. Mech. 17, 975-985, 1968.Referenced on Wolfram|Alpha
Feldman's TheoremCite this as:
Weisstein, Eric W. "Feldman's Theorem." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/FeldmansTheorem.html