The circle and projective homogeneous coordinates (cont.) | Universal Hyperbolic Geometry 7b
Universal hyperbolic geometry is based on projective geometry. This video introduces this important subject, which these days is sadly absent from most undergrad/college curriculums. We adopt the 19th century view of a projective space as the space of one-dimensional subspaces of an affine space of one higher dimension. Thus the projective line is viewed as the space of lines through the origin in two dimensional space, while the projective plane deals with one dimensional and two dimensional subspaces of a 3 dimensional affine xyz space (called respectively projective points and projective lines). This relates to Renassiance artists attempts to render perspectives correctly; we illustrate by looking at a parabola in a somewhat novel way. The usual two dimensional view of the projective plane emerges by intersecting with the plane z=1 in the ambient x,y,z space. This way the circle is the two dimensional representation of a cone: a view relating back to the ancient Greeks. For more information on projective geometry, see WT31-WT41 in my WildTrig series. CONTENT SUMMARY: 2 dimensional geometry the arena of hyperbolic geometry @00:12 page change: adopting a viewing plane @08:07 The circle in projective homogeneous coords.(very important picture in mathematics and physics: special relativity) at the heart of hyperbolic geometry @16:14 ************ Research Gate page: https://www.researchgate.net/profile/... Blog: http://njwildberger.com/ Online courses at openlearning.com (currently Algebraic Calculus One): https://www.openlearning.com/courses/... Please join us for an exciting new approach to one of mathematics' most important subjects! Patreon: / njwildberger Your support would be much appreciated. Wild Egg Maths YT channel: https://www.youtube.com/channel/UCriF... Insights into Mathematics Playlists: • The Algebra of Boole, Logic and Circuit An... (31 videos) • Box Arithmetic: a new framework for Mathem... (18 videos) • Hypergroups and Diffusion Symmetry: an int... (6 videos) • Rational Trigonometry for maths, physics a... (4 videos) • Sociology and Pure Maths (44 videos) • Old Babylonian mathematics and Plimpton 322 (8 videos) • Math Foundations (226 videos) • Math Seminars N J Wildberger (26 videos) • Math History (ancient to modern) (45 videos) • Geometric Linear Algebra (43 videos) • Algebraic Topology (40 videos) • Universal Hyperbolic Geometry (55 videos) • Differential Geometry (34 videos) • Elementary Probability and Statistics (8 videos) • Math Terminology for Incoming Uni Students (9 videos) • Famous Math Problems ( 46 videos) • Elementary Mathematics Explained (K-6) (40 videos) • Ancient Mathematics and insights of Howard... (7 videos) • Wild West Banking: A mathematician goes We... (7 videos) • Playing Go: the ancient oriental board game (19 videos) • Maths and Music (21 videos) • Year 9 Mathematics (review fractions, deci... (10 videos) • Wild Trig: An introduction to Rational Tri... (94 videos) Wild Egg Maths Playlists: • Intro to Algebraic Calculus with Box Arith... (4 videos) • Classical to Quantum (for Members) (64 videos) • Solving Polynomial Equations and the Geode... (45 videos) • De Casteljau Bezier curves and associated ... (20 videos) • Exploring q-series (for Members) (8 videos) • Six: A mathematical exploration (9 videos) • Algebraic Calculus One: a new foundation f... (52 videos) • Advice to prospective research mathematici... (9 videos)
