ar X iv : m at h / 02 06 13 5 v 1 [ m at h . D G ] 1 3 Ju n 20 02 PROJECTIVE PLANES , SEVERI VARIETIES AND SPHERES
نویسنده
چکیده
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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