enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Parallel postulate - Wikipedia

    en.wikipedia.org/wiki/Parallel_postulate

    Nasir al-Din attempted to derive a proof by contradiction of the parallel postulate. [18] He also considered the cases of what are now known as elliptical and hyperbolic geometry, though he ruled out both of them. [17] Euclidean, elliptical and hyperbolic geometry. The Parallel Postulate is satisfied only for models of Euclidean geometry.

  3. Hyperbolic geometry - Wikipedia

    en.wikipedia.org/wiki/Hyperbolic_geometry

    Hyperbolic geometry is more closely related to Euclidean geometry than it seems: the only axiomatic difference is the parallel postulate. When the parallel postulate is removed from Euclidean geometry the resulting geometry is absolute geometry. There are two kinds of absolute geometry, Euclidean and hyperbolic.

  4. Constructions in hyperbolic geometry - Wikipedia

    en.wikipedia.org/wiki/Constructions_in...

    Hyperbolic geometry is a non-Euclidean geometry where the first four axioms of Euclidean geometry are kept but the fifth axiom, the parallel postulate, is changed.The fifth axiom of hyperbolic geometry says that given a line L and a point P not on that line, there are at least two lines passing through P that are parallel to L. [1]

  5. Foundations of geometry - Wikipedia

    en.wikipedia.org/wiki/Foundations_of_geometry

    The new axiom is Lobachevsky's parallel postulate (also known as the characteristic postulate of hyperbolic geometry): [75] Through a point not on a given line there exists (in the plane determined by this point and line) at least two lines which do not meet the given line. With this addition, the axiom system is now complete.

  6. Hyperbolic space - Wikipedia

    en.wikipedia.org/wiki/Hyperbolic_space

    Hyperbolic space, developed independently by Nikolai Lobachevsky, János Bolyai and Carl Friedrich Gauss, is a geometric space analogous to Euclidean space, but such that Euclid's parallel postulate is no longer assumed to hold. Instead, the parallel postulate is replaced by the following alternative (in two dimensions):

  7. Giovanni Girolamo Saccheri - Wikipedia

    en.wikipedia.org/wiki/Giovanni_Girolamo_Saccheri

    Since Euclid's postulate is equivalent to the statement that the sum of the internal angles of a triangle is 180°, he considered both the hypothesis that the angles add up to more or less than 180°. The first led to the conclusion that straight lines are finite, contradicting Euclid's second postulate. So Saccheri correctly rejected it.

  8. List of aperiodic sets of tiles - Wikipedia

    en.wikipedia.org/wiki/List_of_aperiodic_sets_of...

    hyperbolic plane: plane, where the parallel postulate does not hold E 3: Euclidean 3 space: space defined by three perpendicular coordinate axes MLD: Mutually locally derivable: two tilings are said to be mutually locally derivable from each other, if one tiling can be obtained from the other by a simple local rule (such as deleting or ...

  9. Poincaré disk model - Wikipedia

    en.wikipedia.org/wiki/Poincaré_disk_model

    Poincaré disk with hyperbolic parallel lines Poincaré disk model of the truncated triheptagonal tiling.. In geometry, the Poincaré disk model, also called the conformal disk model, is a model of 2-dimensional hyperbolic geometry in which all points are inside the unit disk, and straight lines are either circular arcs contained within the disk that are orthogonal to the unit circle or ...