Journal of Geometry

, Volume 16, Issue 1, pp 103–116 | Cite as

Über gemeinsame Lote Windschiefer geraden in elliptischen Räumen

  • H. R. Friedlein


Let the following motions in a projective elliptic space
(K,π) be called “normal forms”:Subspace-reflections, rotations, the product of a rotation and a point-reflection whose center lies on the axis of the rotation and the product of two rotations, whose axes of rotation are conjugated.
It is shown that all motions of
(K, π) have a normal-form provided any two lines of
(K, π) have a common perpendicular. The latter is true if and only if K is Pythagorean and if the polarity π can be represented by the unit-matrix.


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Copyright information

© Birkhäuser Verlag 1981

Authors and Affiliations

  • H. R. Friedlein
    • 1
  1. 1.Fachbereich 6 - MathematikUniversität EssenEssen

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