Revision #783 → #1192 · back to history
addedErlangen program7215b19a0278
addedHierarchy of geometriesd8e0fe4fd6e7
addedGroup of symmetries of a geometry1a125ccc86f7
addedInvariants under Euclidean vs projective groupsbdcfa01dda51
addedAffine subgroup of projective groupc6641597e22a
addedTraditional spaces as homogeneous spacese57d02bd36b4
addedProjective geometry symmetry group58621ff47f95
addedAffine group as stabilizer of hyperplane at infinitydecee285da27
addedParallelogram is affine, circle is notc49d5215d51f
addedEuclidean group as semidirect product921275ed2857
addedMotion of a geometry2a2c61a760fe
addedUltraparallel theorem via hyperbolic motions3d885cc09b8e
addedOriented elliptic vs oriented spherical geometry07ccbe966fee
addedElliptic geometries with different curvatures2889a525bee4
addedComplex, dual and split-complex numbers as SL(2,R)/Hf75480026f7a
addedHyperbolic, de Sitter and inversive geometries share automorphism groupc69732c88799
addedAnti-de Sitter and conformal Lorentzian spacef0698ad6fa39
addedCovering group of SU(2,2) isomorphic to covering of SO(4,2)9758c94923fa