Abstract
In a desarguesian projective plane we discuss those degenerate conics whose parameters have degree two over the centre of the underlying skew field. Such degenerate conics are closely related with Baer subplanes. This relationship enables us to improve and reformulate in a geometric language some theorems which previously have been established in a purely algebraic way. A geometric description of the family of fundamental chains of these degenerate conies is given.
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Dedicated to Armin Herzer on his 60th birthday.
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Havlicek, H. Degenerate conics revisited. J Geom 38, 42–51 (1990). https://doi.org/10.1007/BF01222894
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DOI: https://doi.org/10.1007/BF01222894