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The projective plane, Boy's surface, and everting the 2-sphere.


Speaker: Robion Kirby, UC Berkeley
Location: 2112 MSB
Start time: Wed, Oct 25 2006, 4:10PM

The projective plane, P2 is the result of identifying antipodal points on the 2-sphere. Like the Klein bottle, it cannot be embedded in 3-space, so is hard to "see", harder than the Klein bottle. Boy's surface is an immersion of P2 in 3-space, which has a circle of double points and a triple point. In this talk, the projective plane will be discussed, a nice description of Boy's surface will be given, and as time permits, it will be used to show how a 2-sphere can be turned inside out through immersions.