Cubic surface: deformation of Whitneys Umbrella to two A1 singularities @davidamadore

Cubic surface: deformation of Whitneys Umbrella to two A1 singularities @davidamadore

Uploaded November 2010 | Updated September 2026, 2 weeks ago

A cubic surface with a line of singular points, known as "Whitney's Umbrella", being deformed to one with two A1 singularities. The umbrella occurs at 3ʺ and 9ʺ in the video.

From the cubic surfaces DVD, madore.org/cubic-dvd

Cubic surface: deformation of Whitneys Umbrella to two A1 singularities

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Cubic surface: deformation of Whitney's Umbrella to two A1 singularities