
Lecture Description
This is the introductory lecture to a series on hyperbolic geometry which introduces a radically new and improved way of treating the subject, making it more algebraic and logical, with improved computational power and many new theorems. In this lecture we summarize the differences between this UNIVERSAL HYPERBOLIC GEOMETRY and traditional courses taught at universities. We briefly review some of the framework introduced by Lobachevsky, Bolyai and Gauss.This course will open up a new area of investigation into geometry, accessible to a broad audience. Let's return to those days where high school teachers and ordinary lay people could contribute to the discovery of new and beautiful facts.Norman Wildberger is also the discoverer of Rational Trigonometry, an important new direction for classical trigonometry (and which really ought to be revolutionizing mathematics education!!) His YouTube site Insights into Mathematics at user: njwildberger also contains series on MathFoundations, History of Mathematics, LinearAlgebra, Rational Trigonometry and even one called Elementary Mathematics (K-6) Explained.
Course Index
- Introduction to Universal Hyperbolic Geometry
- Apollonius and Polarity
- Apollonius and Harmonic Conjugates
- Pappus' Theorem and the Cross Ratio
- First Steps in Hyperbolic Geometry
- The Circle and Cartesian Coordinates
- Duality, Quadrance and Spread in Cartesian Coordinates
- The Circle and Projective Homogeneous Coordinates
- The Circle and Projective Homogeneous Coordinates II
- Computations with Homogeneous Coordinates
- Duality and Perpendicularity
- Existence of Orthocenters
- Theorems using Perpendicularity
- Null Points and Null Lines
- Apollonius and Polarity Revisited
- Reflections in Hyperbolic Geometry
- Reflections and Projective Linear Algebra
- Midpoints and Bisectors
- Medians, Midlines, Centroids and Circumcenters
- Parallels and the Double Triangle
- The J function, sl(2) and the Jacobi identity
- Pure and Applied Geometry: understanding the continuum
- Quadrance and Spread
- Pythagoras' Theorem in Universal Hyperbolic Geometry
- The Triple Quad Formula in Universal Hyperbolic Geometry
- Visualizing Quadrance with Circles
- Geometer's Sketchpad and Circles in Universal Hyperbolic Geometry
- Trigonometric Laws in Hyperbolic Geometry using Geometer's Sketchpad
- The Spread Law in Universal Hyperbolic Geometry
- The Cross Law in Universal Hyperbolic Geometry
- Thales' Theorem, Right Triangles and Napier's Rules
- Isosceles Triangles in Hyperbolic Geometry
- Menelaus, Ceva and the Laws of Proportion
- Trigonometric Dual Laws and the Parallax Formula
- Introduction to Spherical and Elliptic Geometries
- Introduction to Spherical and Elliptic Geometries II
- Areas and Volumes for a Sphere
- Classical Spherical Trigonometry
- Perpendicularity, Polarity and Duality on a Sphere
- Parametrizing and Projecting a Sphere
- Rational Trigonometry: An Overview
- Rational Trigonometry in Three Dimensions
Course Description
This is a complete and relatively elementary course explaining a new, simpler and more elegant theory of non-Euclidean geometry; in particular hyperbolic geometry. It is a purely algebraic approach which avoids transcendental functions like log, sin, tanh etc, relying instead on high school algebra and quadratic equations. The theory is more general, extending beyond the null circle, and connects naturally to Einstein's special theory of relativity. This course is meant for mathematics majors, bright high school students, high school teachers, engineers, scientists, and others with an interest in mathematics and some basic algebraic skills. NJ Wildberger is also the developer of Rational Trigonometry: a new and better way of learning and using trigonometry. Look up for his course in order to familiarize with this new development. He also has recorded very organized and detailed lecture series on Algebraic Topology, History of Mathematic, Linear Algebra, and more.