A Plücker equation for curves in real projective space

Quine, J. R.

doi:10.1090/S0002-9939-1982-0647908-9

A Plücker equation for curves in real projective space
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by J. R. Quine

Proc. Amer. Math. Soc. 85 (1982), 103-107

DOI: https://doi.org/10.1090/S0002-9939-1982-0647908-9

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Abstract:

For smooth closed curves in real projective space we write an equation relating the Plücker characteristics, various winding numbers, and a new characteristic involving pairs of points on the line at infinity. This theorem is a generalization of the Umlaufsatz and also relates directly to Plücker’s equations for algebraic curves.

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