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Projective planes, Severi varieties and spheres

Michael Atiyah·Jurgen Berndt
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Abstract

A classical result asserts that the complex projective plane modulo complex conjugation is the 4-dimensional sphere. We generalize this result in two directions by considering the projective planes over the normed real division algebras and by considering the complexifications of these four projective planes.

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Michael Atiyah, Jurgen Berndt. 2002-06-13. Projective planes, Severi varieties and spheres. https://arxiv.org/abs/math/0206135

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