Circles and Clifford Algebras
نویسنده
چکیده
We study smooth maps from an open subset of a real projective space to a sphere such that all germs of straight lines go to germs of circles (or points). We give a construction of such maps based on representations of Clifford algebras. It provides a complete purely geometric description of Clifford algebras representations in terms of circles. We also describe a connection between our problem and the Hurwitz–Radon theorem about sums of squares.
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