Here’s a fun puzzle for fans of the classical differential geometry of curves and surfaces.
Suppose a curve γ(s):R→R^3, parameterised by arc length s, is a geodesic on a surface of constant Gaussian curvature of –1.
Suppose γ''(s_0) = 0, but γ'''(s_0) ≠ 0.
What does that tells us about the torsion of γ(s) at s=s_0?
Greg Egan /
npub12c…gd38p
2024-10-20 07:19:06
Author Public Key
npub12cuzzqzv8e8y7na77a9zv47mx2v6pec60qs5h7takzmv5p0mw0fsmgd38pPublished at
2024-10-20 07:19:06Event JSON
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