Non-Euclidean geometry - Wikipedia, the free encyclopedia
A non-Euclidean geometry is characterized by a non-vanishing Riemann curvature tensor. Examples of non-Euclidean geometries include the hyperbolic and elliptic geometry, which are contrasted with a ...
en.wikipedia.org/wiki/Non-Euclidean_geometry
The projective models of non-Euclidean geometry can be represented by real matrix transformations on homogeneous coordinates that are serendipitously supported by today's computer graphics transformation hardware and software [10]. The conformal model, however, cannot be implemented using real matrices,
www.geom.uiuc.edu/docs/research/ieee94/node12.html
But, in fact, in terms of the non-Euclidean geometry, despite appearances, these motions preserve distances and angles. The preservation of angles should be detectable if one keeps in mind that the angles are angles between the arcs of circles at their point of intersection.
www.math.umn.edu/~garrett/a02/H2.html
Browse High School Non-Euclidean Geometry ... Non-Euclidean Geometry for 9th Graders [12/23/1994] I would to know if there is non-euclidean geometry that would be appropriate in difficulty for ninth graders to study.
mathforum.org/library/drmath/sets/high_non_euclid.html mathforum.org/library/drmath/sets/high_non_euclid.html
I have recently been studying Euclid (the "father" of geometry), and was amazed to find out about the existence of a non-Euclidean geometry. Being as curious as I am, I would like to know about non-Euclidean geometry.
www.math.toronto.edu/mathnet/questionCorner/noneucgeom.... www.math.toronto.edu/mathnet/questionCorner/noneucgeom.html
non-Euclidean geometry, branch of geometry in which the fifth postulate of Euclidean geometry, which allows one and only one line parallel to a given line through a given external point, is replaced by one of two alternative postulates.
www.factmonster.com/ce6/sci/A0835830.html
Saccheri then studied the hypothesis of the acute angle and derived many theorems of non-Euclidean geometry without realising what he was doing. However he eventually 'proved' that the hypothesis of the acute angle led to a contradiction by assuming that there is a 'point at infinity' which lies on a plane.
www-groups.dcs.st-andrews.ac.uk/~history/HistTopics/Non... www-groups.dcs.st-andrews.ac.uk/~history/HistTopics/Non-Euclidean_geometry.html
One problem is that in Lobachevsky's geometry, there are other lines, through the same points, which do not intersect. And in Riemann's geometry, the proof is not valid as it requires extending the lines infinitely.
www.jimloy.com/geometry/parallel.htm www.jimloy.com/geometry/parallel.htm
A philosophical essay. ... That theory rests on the use of non-Euclidean geometry. There are still many good questions to ask about non-Euclidean geometry; but in treatment after treatment in both popular expositions and in philosophical discussion, the questions consistently seem pointedly not to get asked.
www.friesian.com/curved-1.htm
The "flat" geometry of everyday intuition is called Euclidean geometry (or parabolic geometry), and the non-Euclidean geometries are called hyperbolic ...
mathworld.wolfram.com/Non-EuclideanGeometry.html mathworld.wolfram.com/Non-EuclideanGeometry.html