Mathematical analysis

Coordinate singularity

A coordinate singularity occurs when an apparent singularity or discontinuity occurs in one coordinate frame that can be removed by choosing a different frame. An example is the apparent (longitudinal) singularity at the 90 degree latitude in spherical coordinates. An object moving due north (for example, along the line 0 degrees longitude) on the surface of a sphere will suddenly experience an instantaneous change in longitude at the pole (i.e., jumping from longitude 0 to longitude 180 degrees). In fact, longitude is not uniquely defined at the poles. This discontinuity, however, is only apparent; it is an artifact of the coordinate system chosen, which is singular at the poles. A different coordinate system would eliminate the apparent discontinuity, e.g. by replacing the latitude/longitude representation with an n-vector representation. Stephen Hawking aptly summed this up, when once asking the question, "What lies north of the North Pole?". (Wikipedia).

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Duality and perpendicularity | Universal Hyperbolic Geometry 9 | NJ Wildberger

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From playlist Universal Hyperbolic Geometry

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This video introduces basic facts about points, lines and the unit circle in terms of Cartesian coordinates. A point is an ordered pair of (rational) numbers, a line is a proportion (a:b:c) representing the equation ax+by=c, and the unit circle is x^2+y^2=1. With this notation we determine

From playlist Universal Hyperbolic Geometry

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Computations with homogeneous coordinates | Universal Hyperbolic Geometry 8 | NJ Wildberger

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From playlist Universal Hyperbolic Geometry

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Ex: Identifying the Coordinates of Points on the Coordinate Plane

This video explains how to determine the coordinates of points on the coordinate plane. Complete Video List at http://www.mathispower4u.com Search by Topic at http://www.mathispower4u.wordpress.com

From playlist The Coordinate Plane, Plotting Points, and Solutions to Linear Equations in Two Variables

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What is a Tensor? Lesson 36: Other Notions of Duality

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From playlist What is a Tensor?

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This video introduces cylindrical coordinates and shows how to convert between cylindrical coordinates and rectangular coordinates. http://mathispower4u.yolasite.com/

From playlist Quadric, Surfaces, Cylindrical Coordinates and Spherical Coordinates

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The circle and projective homogeneous coordinates (cont.) | Universal Hyperbolic Geometry 7b

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From playlist Universal Hyperbolic Geometry

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From playlist What is a Tensor?

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From playlist Differential Geometry

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From playlist Lecture Collection | Modern Physics: Einstein's Theory

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From playlist Analysis and its Applications

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algebraic geometry 34 Blowing up a point

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From playlist Algebraic geometry I: Varieties

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Geometric Approach to Invertibility of Random Matrices (Lecture 1) by Mark Rudelson

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From playlist TOPICS IN HIGH DIMENSIONAL PROBABILITY

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Pre-recorded lecture 15: gl-regular Nijenhuis operators (part 4)

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From playlist Commutative algebra

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What are reference angles

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From playlist Angle Relationships

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Stephen Hawking